TWI512391B - A manufacturing method of an electronic device, a manufacturing method of a display device, a method of manufacturing a mask, and a mask - Google Patents

Description

Manufacturing method of electronic device, manufacturing method of display device, manufacturing method of photomask, and photomask

The present invention relates to a method of fabricating an electronic device using photolithography, and more particularly to a method of fabricating a display device. Further, the present invention relates to a photomask used in the above manufacturing method and a method of manufacturing the same.

Patent Document 1 describes a method for forming a pattern with good alignment accuracy in a manufacturing process of an electro-optical device or a semiconductor device. Patent Document 1 describes measuring the amount of shift of the center of the alignment mark on the upper layer side with respect to the center of the alignment mark on the lower layer side, and repeating the specific operation until the offset amount becomes within the allowable value.

Patent Document 2 describes a method of manufacturing a high-quality TFT (Thin Film Transistor) gray-scale mask (also referred to as a "multi-gray mask" in the present invention).

Patent Document 3 describes a method of evaluating a mask pattern and an apparatus therefor.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-209041

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2005-37933

[Patent Document 3] Japanese Patent No. 3136218

Patent Document 1 relates to a method for producing an electro-optical device and a method for producing a semiconductor device, and more particularly to a method for forming a pattern capable of improving the superposition accuracy as compared with the prior method in a method of forming a laminated pattern.

In a manufacturing process of a semiconductor device such as an electro-optical device such as a liquid crystal display device or an LSI (Large Scale Integrated Circuit), a transistor, a diode, and a capacitor are formed by laminating various conductive films or insulating films. Components such as resistors, wiring, etc. (hereinafter referred to as "electronic devices"). At this time, in order to obtain an electronic device having, for example, an electrical characteristic as designed, it is important that the mutual alignment accuracy of the plurality of layers constituting the electronic device. For example, in a thin film transistor (hereinafter referred to as "TFT") used in an active matrix type liquid crystal display device, a pattern of a plurality of layers constituting the TFT is formed in a passivation layer (insulation) If the contact hole of the layer is not accurately aligned with the connection portion on the lower layer side, the correct operation of the liquid crystal display device cannot be ensured. This case is also identical in semiconductor devices such as LSI.

In the laminated structure, a film formation and patterning are often repeated, and a mask having a different transfer pattern is used for each of the laminated films, and patterning is performed by a photolithography step. At this time, the alignment at the time of patterning can be performed by referring to the alignment mark provided on the lower layer side at the time of patterning on the upper layer side.

However, the method disclosed in Patent Document 1 is useful even for the measurement and evaluation of the alignment error, and it cannot be said that the alignment error itself can be effectively reduced only by this method.

Furthermore, according to the study by the inventors, there are a plurality of causes of alignment errors generated by electronic devices having a laminated structure, which are superimposed on the manufactured electronic devices.

Patent Document 2 describes a method for preventing the use of a plurality of photolithography steps, that is, overlapping shifts of a plurality of drawing steps, in the manufacturing step of the gray scale mask, which may cause use. The TFT manufactured by the photomask generates a malfunction.

Further, Patent Document 3 discloses that in the drawing step of the photomask, when the pattern is drawn on the resist film, the pattern based on the design coordinate data does not necessarily completely match. Therefore, the patent literature In 3, it is described that the mask pattern is evaluated from the viewpoint of the arrangement shift of the overall pattern.

That is, the positional shift represented by the alignment error of the electronic device is affected by the overlap precision of the plurality of layers mentioned in Patent Document 1, and is also affected by the transfer pattern currently possessed by the photomask used. The influence caused by the offset of the coordinates.

In addition, when forming a multilayer structure of an electronic device, different masks are placed on the exposure device for each layer, and alignment marks and laminated patterns are read. According to the study by the inventors, it was found that the alignment error (EA, alignment error) derived from the exposure apparatus used at this time was about ±0.6 μm.

However, according to the research of the present inventors, it is understood that the reticle used has its own alignment error component (the offset component from the ideal coordinate appearing in the one-time drawing described in Patent Document 3 is overlapped by a plurality of times of drawing) On the other hand, the alignment error component EM derived from the mask is approximately ±0.5 μm which is approximately the same level as the above EA.

Furthermore, it should be noted here that the evaluation of the alignment error generated in the electronic device having the laminated structure is performed by the evaluation of the relative offset of the layers compared to the absolute values of the coordinates of the layers. Suitable. In other words, if the layers 1 and 2 have the same amount of alignment error components in the same direction with respect to the ideal ideal coordinates, the overlap accuracy does not deteriorate, and the performance as an electronic device is not greatly adversely affected. However, if there are alignment error components in different directions, there is a case where an alignment error amount which may cause malfunction of the device is caused by superposition thereof.

Accordingly, the present invention has been made in view of the above circumstances, particularly in research for a method of reducing the alignment error component EM. That is, an object of the present invention is to obtain an alignment error component which can be reduced in the photomask itself used in the manufacturing process of the electronic device, and the coordinate offset component appearing in the first drawing is overlapped by a plurality of times of drawing. A method of manufacturing an electronic device that synthesizes and produces an alignment error component EM.

In order to solve the above problems, the present invention has the following configuration. The present invention is the following composition 1 The manufacturing method of the electronic device of the ninth aspect, the manufacturing method of the photomask of the following 10-12, the photomask of the following structures 13-15, and the manufacturing method of the display device of the following structure 16.

(Composition 1)

According to a first aspect of the present invention, in a method of manufacturing an electronic device, the first thin film pattern forming step includes: forming a first thin film formed on the substrate or a first resist formed on the first thin film The film is formed by patterning the first film by using a first photolithography step of the first exposure using the first mask, and a second film pattern forming step of the second film formed on the substrate Or the second resist film formed on the second film is subjected to a second photolithography step of using the second exposure of the second mask, and the second film is patterned to be different from the first film pattern. The first photomask and the second photomask have a first transfer pattern including a light transmitting portion, a light blocking portion, and a semi-transmissive portion, and the second mask is the same as the first mask In the second photomask, the second photomask includes a second transfer pattern formed by performing additional processing on the first transfer pattern included in the first photomask.

(constituent 2)

The second aspect of the present invention provides a method of manufacturing an electronic device, comprising the steps of: forming a first thin film on a substrate; and forming a first thin film pattern by the first thin film or the first thin film The first resist film on the first film is subjected to a first photolithography step using the first exposure of the first photomask, and the first thin film is patterned, and formed on the substrate on which the first thin film pattern is formed. a second film forming step; and a second film forming step of the second film or the second film formed on the second film, including the second exposure using the second mask Light microstep And patterning the second film into a shape different from the first film pattern; and the first mask and the second mask have a first turn including a light transmitting portion, a light blocking portion, and a semi-light transmitting portion The second pattern mask is the same as the first mask, and the second mask has additional processing for the first transfer pattern of the first mask. The second transfer pattern is formed.

(constitution 3)

According to a third aspect of the invention, in the method of manufacturing the electronic device of the first or second aspect, the second photomask is the same photomask as the first photomask, and is included in the first transfer pattern. The edges of the light shielding portion and the semi-light transmitting portion are defined by one drawing step.

(construction 4)

The method of manufacturing an electronic device according to any one of the first to third aspects of the present invention, characterized in that the first thin film pattern forming step and the second thin film pattern forming step are differently applied.

(Constituent 5)

The method of manufacturing an electronic device according to any one of claims 1 to 4, wherein the first film or the first resist film and the second film or the second resist film have Different photosensitivity.

(constituent 6)

The method of manufacturing an electronic device according to any one of claims 1 to 5, wherein the first film or the first resist film comprises a positive photosensitive material, the second film or the above The second resist film contains a negative photosensitive material.

(constituent 7)

The method of manufacturing an electronic device according to any one of claims 1 to 6, wherein the first film or the first resist film comprises a negative photosensitive material, the second film or the above The second resist film is a positive photosensitive material.

(Composition 8)

The method of manufacturing the electronic device according to any one of the first to seventh aspects of the present invention, characterized in that the second transfer pattern of the second photomask has the first photomask When the first transfer pattern is subjected to the additional processing, the additional processing is performed by removing one of the first transfer patterns to form the second transfer pattern.

(constituent 9)

According to a fifth aspect of the present invention, in the method of manufacturing the electronic device of the eighth aspect, the first transfer pattern has an exposure device that is used for exposure by using the first photomask, and the line is not resolved. Wide mark pattern.

The present invention is a method of manufacturing a photomask, which is characterized by the following constitutions 10 to 12.

(construction 10)

The structure 10 of the present invention is a method for producing a photomask, which is characterized in that a first thin film pattern obtained by patterning a first thin film is laminated on the same substrate, and the second thin film is formed. An electronic device having a laminated structure of a patterned second thin film pattern; wherein the photomask has a transfer pattern including a light shielding portion, a semi-transmissive portion, and a light transmitting portion formed on the transparent substrate; and the photomask The manufacturing method includes the steps of: preparing a photomask substrate having a semi-transmissive film and a light-shielding film sequentially on a transparent substrate; and performing the first etching on the first resist film formed on the light-shielding film a step of forming a first resist pattern for forming the light-shielding portion and defining a tentative pattern of the semi-transmissive portion, and a first etching step of using the first resist pattern as a mask Etching the above mask a light film; a step of forming a second resist film on the entire surface including the formed light-shielding portion and the tentative pattern; and forming the second resist pattern by the second drawing a second resist pattern of the semi-transmissive portion; a second etching step of etching the semi-transmissive film by using the tentative pattern and the second resist pattern as a mask; and a third etching step The tentative pattern is removed by etching using the second resist pattern as a mask.

(Structure 11)

The structure 11 of the present invention is a method for producing a photomask, which is characterized in that a first thin film pattern obtained by patterning a first thin film is laminated on the same substrate, and the second thin film is formed. An electronic device having a laminated structure of a patterned second thin film pattern; wherein the photomask includes a first transfer pattern for forming the first thin film pattern on a transparent substrate; and the method for manufacturing the photomask includes a step of preparing a mask base having a semi-transmissive film and a light-shielding film sequentially on the transparent substrate; and a first transfer pattern forming step by respectively applying the semi-transmissive film and the light-shielding film Forming the photolithography step to form the first transfer pattern; and the first transfer pattern has a shape for forming the first thin film pattern of the electronic device by exposure And including a mark pattern of a line width which is not resolved by the exposure device used in the exposure, wherein the shape is the second film pattern forming the electronic device, and the mark may be One of the first transfer patterns defined by the pattern is removed by additional processing Remover.

(construction 12)

According to a fourth aspect of the present invention, in a method of manufacturing a photomask according to the tenth or eleventh aspect, the photomask substrate is formed by sequentially laminating the semi-transmissive film and the light shielding film having different etching characteristics from each other on the transparent substrate. Founder.

(construction 13)

The structure 13 of the present invention is a photomask for manufacturing a first thin film pattern in which a first thin film is patterned on a same substrate, and patterning the second thin film. The electronic device having the laminated structure of the second thin film pattern; and the first transfer pattern, wherein the first transfer pattern is formed by patterning the semi-transmissive film and the light-shielding film formed on the transparent substrate And forming the first thin film pattern, wherein the first transfer pattern has a shape for forming a shape of the first thin film pattern of the electronic device by exposure, and including the exposure The exposure device used at the time, without using the mark pattern of the line width, is the second transfer pattern for forming the second thin film pattern of the electronic device, and the first mark can be defined by the mark pattern One of the portions of the transfer pattern is removed by additional processing.

(construction 14)

According to a fourth aspect of the invention, the second transfer pattern includes a light-transmitting portion surrounded by the semi-transmissive portion, a light-transmitting portion surrounded by the light-shielding portion, and surrounded by the light-shielding portion. The semi-transmissive portion, the light-shielding portion surrounded by the semi-transmissive portion, the light-shielding portion surrounded by the light-transmitting portion, and the semi-transmissive portion surrounded by the light-transmitting portion.

(construction 15)

The structure 15 of the present invention is the photomask of the 13 or 14, wherein the marking pattern includes 0.3 to 1.5 μm of a portion of the light shielding portion surrounding the first transfer pattern. a semi-transmissive portion or a light-transmitting portion of the width.

(construction 16)

The present invention is a method of manufacturing a display device according to the present invention, which is a method of manufacturing an electronic device according to any one of 1 to 9.

According to the manufacture of the electronic device of the present invention, the same mask is directly used for the plurality of layers, or the transfer pattern is changed by additional processing, whereby the positions of the masks used for the plurality of layers can be made. The offset tends to be uniform, resulting in improved overlay accuracy. Furthermore, the conditions of the photolithography step are changed for different layers or the transfer pattern (addition processing) of the mask is changed. However, in the latter case, no new processing is required. Alignment error component. In any case shown as an embodiment of the present invention, the edges of the transfer pattern for transferring each of the plurality of layers are defined by one drawing in the manufacturing process of the mask.

According to the present invention, it is possible to obtain an alignment error component EM which is at least reduced in the photomask used in the manufacturing steps of the electronic device, that is, the coordinate offset component appearing in the first drawing is overlapped by a plurality of times of drawing A method of manufacturing an electronic device that shifts and synthesizes alignment errors.

10‧‧‧Transparent substrate

11‧‧‧Transmission Department

12‧‧‧ semi-transmission department

13‧‧‧Lighting Department

15‧‧‧ alignment mark

20‧‧‧ Semi-transparent film

21‧‧‧ Semi-transparent film pattern

30‧‧‧Shade film

31‧‧‧Shade film pattern

40a‧‧‧1st resist film (positive type)

40b‧‧‧1st resist film (negative type)

41a‧‧‧1st resist pattern (positive type)

41b‧‧‧1st resist pattern (negative type)

45‧‧‧Additional processing resist film

46‧‧‧Additional processing resist pattern

47‧‧‧Additional processing resist film

48‧‧‧Additional processing resist pattern

50‧‧‧Device substrate

60‧‧‧1st film

61‧‧‧1st film pattern

70‧‧‧2nd film

70a‧‧‧2nd film (positive type)

70b‧‧‧2nd film (negative type)

71‧‧‧2nd film pattern

71a‧‧‧2nd film pattern (positive type)

71b‧‧‧2nd film pattern (negative type)

80‧‧‧ mark pattern

90‧‧‧Contact hole

A‧‧‧Mask

B‧‧‧Mask

D1‧‧‧ distance

D2‧‧‧ distance

D1‧‧‧ distance

D2‧‧‧ distance

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing an aspect of a reticle used in the step of manufacturing an electronic device of Embodiment 1 of the present invention. (a) is a plan mode diagram, (b) is a cross-sectional pattern diagram, and (c) is a transmission light amount distribution on a point chain line shown in (a) and a resist material used in the first film pattern formation step. Resolution threshold.

2(a), (b-1), (b-2), (c), (d-1), and (d-2) show the steps in the steps of manufacturing the electronic device of the first embodiment of the present invention. 1 Schematic diagram of a film pattern forming step.

Fig. 3 is a schematic view showing a reticle used in the second film pattern forming step of the first embodiment of the present invention, which is the same as the photomask shown in Fig. 1. (a) a flat pattern diagram, (b) In the cross-sectional pattern diagram, (c) shows the transmitted light amount distribution on one of the dot links shown in (a) and the resolution threshold of the resist material used in the second thin film pattern forming step.

4(a-1), (a-2), (b-1), (b-2), and (c) show the formation of the second thin film pattern in the step of manufacturing the electronic device of the first embodiment of the present invention. Schematic diagram of the steps.

Fig. 5 is a schematic view showing an aspect of a reticle used in the step of manufacturing the electronic device of the embodiment 2 of the present invention. (a) is a plan mode diagram, (b) is a cross-sectional pattern diagram, and (c) is a transmission light amount distribution on a point chain line shown in (a) and a resist material used in the first film pattern formation step. Resolution threshold.

6(a), (b-1), (b-2), (c), (d-1), and (d-2) show the steps in the steps of manufacturing the electronic device of the second embodiment of the present invention. 1 Schematic diagram of a film pattern forming step.

Fig. 7 is a schematic view showing a reticle similar to the reticle shown in Fig. 5, that is, a reticle used in the second film pattern forming step of the second embodiment of the present invention. (a) is a plan mode diagram, (b) is a cross-sectional pattern diagram, and (c) is a transmission light amount distribution on a dot chain line shown in (a) and a resist material used in the second thin film pattern formation step. Resolution threshold.

8(a-1), (a-2), (b-1), (b-2), and (c) show the formation of the second thin film pattern in the step of manufacturing the electronic device of the second embodiment of the present invention. A schematic diagram of the steps.

Fig. 9 is a schematic view showing an aspect of a reticle used in the step of manufacturing the electronic device of the embodiment 3 of the present invention. (a) is a plan mode diagram, (b) is a cross-sectional pattern diagram, and (c) is a transmission light amount distribution on a point chain line shown in (a) and a resist material used in the first film pattern formation step. Resolution threshold.

10(a), (b-1), (b-2), (c), (d-1), and (d-2) show the steps in the steps of manufacturing the electronic device of the embodiment 3 of the present invention. 1 Schematic diagram of a film pattern forming step.

Fig. 11 is a schematic view showing a reticle used in the second film pattern forming step of the third embodiment of the present invention, which is obtained by additionally processing the reticle shown in Fig. 9. (a) is a plan mode diagram, (b) is a cross-sectional pattern diagram, and (c) is a transmission light amount distribution on a dot chain line shown in (a) and a resist material used in the second thin film pattern formation step. Resolution threshold value.

12(a-1), (a-2), (b-1), (b-2), and (c) show the formation of the second thin film pattern in the step of manufacturing the electronic device of the third embodiment of the present invention. Schematic diagram of the steps.

Figures 13(a-1), (a-2), (b-1), (b-2), (c), (d), (e), (f-1), (f-2) A schematic diagram showing the steps of additional processing described as the fourth embodiment for obtaining the photomask shown in Fig. 11 is shown.

14(a-1), (a-2), (b-1), (b-2), (c), (d), (e), (f), (g), (h), (i-1) and (i-2) are schematic diagrams showing the steps of additional processing described in the fifth embodiment for obtaining the photomask shown in Fig. 11.

Fig. 15 is a schematic view showing a mask of Mask A used in the first film pattern forming step in the step of the electronic device of Comparative Example 1 of the prior art. (a) is a plan mode diagram, (b) is a cross-sectional pattern diagram, and (c) is a transmission light amount distribution on a point chain line shown in (a) and a resist material used in the first film pattern formation step. Resolution threshold.

16(a), (b-1), (b-2), (c), (d-1), and (d-2) show the steps of manufacturing the electronic device of Comparative Example 1 of the prior art. A schematic view of the first thin film pattern forming step.

Fig. 17 is a schematic view showing a mask for Mask B used in the second film pattern forming step in the step of the electronic device of Comparative Example 1 of the prior art. (a) is a plan mode diagram, (b) is a cross-sectional pattern diagram, and (c) is a transmission light amount distribution on a point chain line shown in (a) and a resist material used in the first film pattern formation step. Resolution threshold.

18(a-1), (a-2), (b-1), (b-2), and (c) show the second thin film pattern in the step of manufacturing the electronic device of Comparative Example 1 of the prior art. A pattern diagram of the formation steps.

19(A)-(C) are schematic views showing an embodiment of a method of manufacturing a photomask for reducing the alignment error component EM generated in the mask manufacturing step.

20(D) to (I) are schematic diagrams showing an embodiment of a method of manufacturing a photomask for reducing the alignment error component EM generated in the mask manufacturing step, following FIG.

21(A)-(D) show a method of manufacturing a photomask using a secondary photolithography step. A pattern diagram for determining the distances D1 and D2 at which the transfer patterns of the respective steps are offset from each other.

The invention is based on the invention that in the manufacture of the multilayer structure of the electronic device, the alignment error can be reduced as long as the mask can be patterned by using a mask having a plurality of layers formed by the same drawing step. . That is, even if one mask is compared with the design data of the mask, even if the measured alignment error component is present, the plurality of layers included in the laminated structure of the electronic device have the same alignment error component. The patterning of the mask is effective in that the alignment error component EM is not visualized in the electronic device as the final product. That is, theoretically, it is not impossible to set the component of EM to zero.

For example, even if it is difficult to manufacture a plurality of masks having the same tendency of alignment errors, it is possible to transfer a transfer pattern defined by the same drawing step by using one mask and (additional processing as necessary) In the photomask, when the mask is applied to a plurality of layers, the pattern for transfer has a tendency to have the same alignment error, so that the alignment error component EM can be made substantially zero.

Therefore, the method for manufacturing an electronic device according to the present invention includes the first thin film pattern forming step of including the first film formed on the substrate or the first resist formed on the first film. Forming the first thin film by the first photolithography step of the first exposure of the photomask; and forming the second thin film pattern forming step on the second thin film formed on the substrate The second resist film on the film 2 includes a second photolithography step including the second exposure using the second mask, and the second film is patterned into a shape different from the first film pattern. In the method of manufacturing an electronic device of the present invention, the first photomask and the second photomask have a first transfer pattern including a light transmitting portion, a light blocking portion, and a semi-transmissive portion, and the second photomask a photomask that is the same as the first photomask, or the second photomask has a second transfer pattern that is formed by additionally processing the first transfer pattern of the first photomask. .

Specifically, the method of manufacturing an electronic device according to the present invention may include the steps of: forming a first film on a substrate; and forming a first film pattern by the first film or the first film; 1 that the first film is patterned by using a first photolithography step of using the first exposure of the first mask, and the second film is formed on the substrate on which the first film pattern is formed; In the second thin film pattern forming step, a second photolithography step including the second exposure using the second photomask is performed on the second thin film or the second resist film formed on the second thin film. The second thin film is patterned into a shape different from the first thin film pattern. In the method of manufacturing an electronic device of the present invention, the first photomask and the second photomask have a first transfer pattern including a light transmitting portion, a light blocking portion, and a semi-transmissive portion, and the second photomask a photomask that is the same as the first photomask, or the second photomask has a second transfer pattern that is formed by additionally processing the first transfer pattern of the first photomask. .

The second photomask used in the method of manufacturing an electronic device of the present invention is the same as the first photomask, or the second photomask has the first transfer for the first photomask. The pattern is subjected to additional processing to form a second transfer pattern. In other words, the first photomask and the second photomask are formed with the transfer pattern in the same transfer region on the same transparent substrate. Further, the second transfer pattern can be determined by the drawing step for forming the first transfer pattern by the following method. Therefore, the alignment error component EM due to the photomask itself used in the manufacturing steps of the electronic device can be reduced. In addition, the transfer region refers to a region where a transfer pattern located in the region is to be transferred onto the transfer target by exposure.

In the manufacturing method of the prior electronic device, a plurality of photomasks each having a different transfer pattern or a photomask having a plurality of transfer patterns are used for the plurality of layers of the electronic device ( Multi-gray reticle). In either case, the plurality of transfer patterns each include a coordinate offset generated at the time of drawing, and are displayed as alignment errors by overlapping each other. No reduction produces an alignment error of about ±0.5 μm. The method of dividing EM. Therefore, it is only accepted that the alignment error component EM is added with an alignment error of about 1 μm or more which is caused by an alignment error of about ±0.6 μm by the exposure device (EA). Further, the alignment error caused by the exposure device is a total error of the reading accuracy of the alignment mark at the stage of mounting the photomask on the exposure device and the mechanical precision set at the stage of the mask substrate to be read. According to the present invention, in theory, it is possible to substantially prevent an alignment error other than the alignment error caused by the exposure device.

When etching is performed in the manufacturing steps of the electronic device of the present invention, either dry etching or wet etching can be applied. It is more preferable to apply wet etching in consideration of etching isotropy, manufacturing cost, and the like. In the mask manufacturing, it is also preferable to apply wet etching. Further, in the case of applying dry etching, it is necessary to preliminarily consider the amount of film reduction of the resist (photosensitive material) due to etching of the film.

The photomask of the present invention includes a photomask including a light-shielding portion, a semi-transmissive portion, and a transfer pattern of the light-transmitting portion. As described in the following configuration, it can be produced by using a mask base on which a semi-transmissive film and a light-shielding film are sequentially formed on a transparent substrate.

Further, as described in the following embodiments, there is a case where any one of the laminated structures of the electronic device using the photosensitive material is used, and on the other hand, there is also a material which does not have photosensitivity. Happening. For example, when the first film is a photosensitive material, the first film itself may be patterned by a photolithography step to form a target layer. On the other hand, when the first film is a material having no photosensitivity, in order to pattern the first film, a resist film (resist film) is formed on the surface of the first film, and patterned. An etching mask can be formed to etch the first film. This is also the case in the case of the second film. In this sense, it is expressed as "the first film or the first resist film formed on the first film". That is, the first film (Yu Wei In the case of a photosensitive film or the first resist film formed on the first film (when the first film does not have photosensitivity).

Further, in general, the resist film on the first film or the first film or the resist film on the second film or the second film is sequentially patterned to become each of the first film pattern and the second film pattern. The film is a different raw material and thus has different etching characteristics, but may be the same raw material. Further, it may be formed by one film forming step.

In the method of manufacturing the electronic device of the present invention, the second photomask is the same as the photomask of the first photomask, and the edges of the light shielding portion and the semi-transmissive portion included in the first transfer pattern are It is delimited by one drawing step. That is, when the first transfer pattern is formed, it is not necessary to overlap the plurality of drawing steps, and therefore, the overlap of the patterns formed by the different drawing steps does not occur.

In the method of manufacturing an electronic device of the present invention, it is preferable that the first thin film pattern forming step and the second thin film pattern forming step are different.

The "different conditions" include that the resist (photosensitive material) film is different, the resist process is different, and the exposure conditions are different.

The resist (photosensitive material) film or the resist process is different in the type of the resist material used in each of the first film pattern forming step and the second film pattern forming step, and the developing condition of the resist ( The composition, concentration, development time, etc. of the developer are different. Therefore, even when the first photomask and the second photomask are the same photomask, the same photomask can be used to form the second thin film pattern different from the first thin film pattern. In addition, even when the second transfer pattern (also referred to as "second transfer pattern for additional processing") formed by performing additional processing on the first transfer pattern of the first photomask is used, A second thin film pattern different from the first thin film pattern can be formed.

Alternatively, the resist (photosensitive material) film may have a difference in coating film thickness between the first film or the first resist film and the second film or the second resist film.

The exposure conditions are different, and the application conditions of the first exposure and the second exposure are different. For example, the amount of light to be irradiated may be different depending on the irradiation intensity of the light source applied in the first exposure and the second exposure or the irradiation time. For example, the amount of irradiation light of the first exposure may be made larger or opposite to the second exposure.

In the method of manufacturing an electronic device of the present invention, it is preferable that the first film or the first resist film has different photosensitivity from the second film or the second resist film.

The term "different sensitivity" refers to a difference between the resist materials, for example, a difference between a negative type and a positive type, or a difference in sensitivity characteristics (a characteristic curve of photosensitivity versus amount of light) The difference is also the difference in developability with respect to the developer. Since the first film or the first resist film and the second film or the second resist film have different photosensitivity, even when the same photomask or the additional photomask of the second transfer pattern is used, Further, a second film pattern different from the first film pattern may be formed.

In the method of manufacturing an electronic device of the present invention, the first film or the first resist film may include a positive photosensitive material, and the second film or the second resist film may be a negative photosensitive material. Since the first film or the first resist film contains a positive photosensitive material, and the second film or the second resist film is a negative photosensitive material, even if the same photomask or additional processing is used, the second transfer is used. In the case of the mask of the pattern, the second film pattern different from the first film pattern can be surely formed.

In the method of manufacturing an electronic device of the present invention, the first film or the first resist film may include a negative photosensitive material, and the second film or the second resist film may be a positive photosensitive material. Since the first film or the first resist film contains a positive photosensitive material, and the second film or the second resist film is a negative photosensitive material, even if the same photomask or the additional processed second transfer is used, In the case of a patterned photomask, the second thin film pattern different from the first thin film pattern can be surely formed.

In the method of manufacturing an electronic device of the present invention, the second transfer pattern included in the second photomask is applied to the first transfer pattern included in the first photomask. In the additional processing, the second transfer pattern can be formed by removing one of the first transfer patterns.

The second transfer pattern has a pattern edge formed as a pattern edge when the first transfer pattern is formed at the stage of manufacturing the first photomask. In other words, in the step of performing additional processing for forming the second transfer pattern, even when a new drawing step is performed, the pattern of the second transfer pattern is not newly formed in the new drawing step. edge. In other words, the drawing step performed in the step of forming the second transfer pattern does not have the function of forming the pattern edge of the second transfer pattern. The second transfer pattern can be obtained by performing additional processing for removing the isolated portion of the first transfer pattern. Therefore, the second transfer pattern is actually only defined by one drawing, and is defined when the first transfer pattern is drawn. Therefore, there is no depiction of the two transfer patterns. Position offset. Therefore, the alignment error component EM due to the alignment error of the photomask itself used in the manufacturing steps of the electronic device can be reduced.

In the method of manufacturing an electronic device of the present invention, it is preferable that the first transfer pattern has a mark pattern of a line width which is not resolved by an exposure device used for exposure by using the first photomask.

In the above-described additional processing, when the second transfer pattern is formed by removing one of the first transfer patterns, the mark pattern can be used. In other words, the marking pattern may be a semi-transmissive portion (a portion where the semi-transparent film on the transparent substrate is exposed) or a transmissive portion of the line width which is not resolved by the exposure device by the light shielding portion. (the portion where the transparent substrate is exposed). At the time of additional processing, the mark pattern may be a boundary to remove a portion of the first transfer pattern located on one side of the mark pattern. As a result, since the second transfer pattern is originally included in the first transfer pattern, there is no mutual drawing position shift therebetween. Therefore, the above-described alignment error component EM can be reduced in the manufacturing steps of the electronic device.

Furthermore, when the mask is used in the case where the mask substrate of the semi-transmissive film and the light-shielding film is sequentially formed on the transparent substrate, the marking pattern can be set by removing the light-shielding film. A semi-transmissive portion formed by marking the shape of the pattern. Further, in this case, the marking pattern may be formed as a light transmitting portion formed by removing both of the laminated semi-transmissive film and the light shielding film into the shape of the marking pattern. The marking pattern is preferably such that it does not resolve at the time of exposure (the threshold value of the photosensitivity of the resist material is not reached), so the former is preferred.

If the line width of the mark pattern is too large, the image is defective in the first exposure. On the other hand, if the line width of the mark pattern is too small, it is difficult to absorb the alignment error between the first transfer pattern formed on the mask in the drawing step (described below) necessary for additional processing. . In view of this, the line width of the above marking pattern is preferably from 0.3 μm to 1.5 μm, more preferably from 0.3 to 1.0 μm.

The exposure apparatus is an exposure apparatus known as an exposure apparatus for an LCD (Liquid Crystal Display) or an exposure apparatus for liquid crystal, and has, for example, an NA (opening number) of its optical system of 0.06 to 0.10, σ ( The coherency is an optical system of an equal magnification exposure in the range of 0.5 to 1.0, and more preferably, the NA is 0.08 to 0.1 and the σ is in the range of 0.8 to 0.9. In such an exposure apparatus, the minimum width (resolution limit) of the image that can be resolved can be set to about 3 μm. Moreover, the present invention can also be applied to the transfer using a wider range of exposure devices. For example, it can be set that the range of NA is 0.06 to 0.14 or 0.06 to 0.15. There is also a need in an exposure apparatus having a high resolution of NA exceeding 0.08, and thus it is also applicable to such. As the wavelength of the exposure light, those including i-rays, h-rays, and g-rays can be used. It is preferable that all of the exposure light including the i-ray, the h-ray, and the g-ray is used for the amount of the light to be irradiated, but it is also possible to use an optical filter or the like to cut off light other than the desired wavelength (for example, i-ray) as needed.

When performing additional processing, the first film, the first resist film, the second film, or the second resist film may be used as a positive photosensitive material. Further, the first film, the first resist film, the second film or the second resist film may be made of a negative photosensitive material.

The types of the first film and the second film can be appropriately selected depending on the type of electronic device to be manufactured. For example, the first film and the second film may be an electrode layer and an insulating layer, respectively.

A photomask manufactured by the method for producing a photomask of the present invention is used for manufacturing a first thin film pattern in which a first thin film is patterned on a same substrate, and a second thin film is patterned. A photomask of an electronic device having a laminated structure of the second thin film pattern. The photomask includes a photomask including a light-shielding portion, a semi-transmissive portion, and a transfer pattern of the light-transmitting portion.

The method for manufacturing a reticle according to the present invention includes the steps of: preparing a reticle substrate having a semi-transmissive film and a light-shielding film sequentially on a transparent substrate; and forming a first anti-reflection film formed on the light-shielding film The etching film is drawn for the first time to form a first resist pattern for forming the light shielding portion and defining a tentative pattern of the semi-transmissive portion, and a first etching step for forming the first resist pattern Etching the light-shielding film as a mask; forming a second resist film on the entire surface including the formed light-shielding portion and the tentative pattern; and forming the second resist film for the second time a second resist pattern for forming the semi-transmissive portion; a second etching step of etching the semi-transmissive film by using the tentative pattern and the second resist pattern as a mask; and a third etching In step, the tentative pattern is removed by etching the second resist pattern as a mask.

According to the method for producing a photomask of the present invention, it is possible to manufacture a photomask which can form a first thin film pattern and a second thin film pattern of a desired electronic device by using the same photomask. Further, the alignment error component EM generated by the transfer pattern included in the photomask may be substantially not generated between the thin film patterns.

The above-mentioned "sequential laminated semi-transmissive film and light-shielding film" includes not only the case of directly laminating, but also other films can be placed within a range that does not impair the effects of the present invention. For example, the etching characteristics of the semi-transmissive film and the light-shielding film are similar (the etching selectivity is insufficient) At the same time, an etch stop film may be interposed between the semi-transmissive film and the light-shielding film.

In addition, the expression of the first resist film and the first resist pattern in the above is distinguished from the first resist film and the first resist pattern used in the description of the process of manufacturing an electronic device. It is used for the purpose of describing the manufacturing steps of the photomask.

A photomask manufactured by the method for producing a photomask of the present invention is used for manufacturing a first thin film pattern in which a first thin film is patterned on a same substrate, and a second thin film is patterned. A photomask of an electronic device having a laminated structure of the second thin film pattern. The photomask includes a first transfer pattern for forming the first thin film pattern on a transparent substrate. A method of manufacturing a photomask according to the present invention includes the steps of: preparing a photomask substrate having a semi-transmissive film and a light-shielding film sequentially formed on the transparent substrate; and forming a first transfer pattern by the semi-transparent Each of the light film and the light-shielding film is patterned by photolithography to form the first transfer pattern. Here, the first transfer pattern has a shape for forming the first thin film pattern of the electronic device by exposure, and includes no image formation by the exposure device used in the exposure. The line width mark pattern. In the photomask of the present invention, the shape is characterized in that one part of the first transfer pattern defined by the mark pattern is removed by additional processing in order to form the second thin film pattern of the electronic device. .

According to the method of manufacturing a photomask of the present invention, the photomask can be manufactured such that the first transfer pattern has a shape including a specific mark pattern, and a part of the first transfer pattern defined by the mark pattern can be partially used. Additional processing and removal. By using the photomask for the manufacturing method of the electronic device including the above-described specific additional processing, a method of manufacturing an electronic device capable of reducing the alignment error component EM caused by the photomask can be obtained.

In the method of manufacturing a reticle according to the aspect of the invention, preferably, the reticle base is formed by sequentially laminating the semi-transmissive film and the light-shielding film having different etching characteristics from each other on the transparent substrate. By. Since the mask base is formed by sequentially laminating the semi-transmissive film and the light-shielding film having different etching characteristics from each other on the transparent substrate, it is easy to One of the first transfer patterns defined by the mark pattern is removed by additional processing.

The etching characteristics are different from each other, which means that the other one is resistant to the etching environment. Specifically, the light shielding film and the semi-transmissive film are preferably raw materials having resistance to an etchant (etching liquid or etching gas) of each other.

In the reticle of the reticle of the present invention and the photographic mask which can be used in the manufacturing method of the electronic device of the present invention, if a specific semi-transparent film is used as the raw material, the Cr compound (the oxide of Cr) is removed. , other than a Si compound (SiO ₂ , SOG), a metal halide compound (a nitride such as TaSi, MoSi, WSi, or the like, a nitrogen oxide, etc.), a nitride, a carbide, an oxynitride, or a oxynitride A Ti compound such as TiON can also be used.

The material of the light-shielding film may be a compound of Ta, Mo, W or the like (including the above metal) in addition to Cr or a Cr compound (oxide, nitride, carbide, nitrogen oxide, carbon oxynitride, etc.). Telluride) and so on.

Therefore, in consideration of the etching selectivity of each, for example, when a Si compound, a metal telluride compound, or a Ti compound is used for the semi-transmissive film, the light-shielding film material is preferably a combination of Cr or a Cr compound. It can also be set to the opposite combination.

It is preferable that the light-shielding film and the semi-transmissive film are substantially not exposed to the exposure light (the optical density OD is 3 or more) in the laminated state, but may be a part of the permeable light that can be transmitted depending on the use of the mask. (for example, transmission rate ≦ 20%). Further, the term "shading film" as used in the present specification does not necessarily have to be completely light-shielding. It is preferable to make the optical density OD 3 or more by laminating with a light-transmitting film. More preferably, the optical density OD is preferably 3 or more by the light shielding film alone. The OD can be set, for example, to the representative wavelength when the representative wavelength of the exposure wavelength is set to g-ray.

As the semi-transmissive film, it is preferable to use an exposure light transmittance of 20 to 80%, more preferably 30 to 70%, and a phase shift amount of 90 degrees or less, more preferably 60 degrees or less. Here, the exposure light transmittance can be a translucent film when the transmittance of the transparent substrate is set to 100%. The overtone, that is, the representative wavelength of the light used for exposure. The phase shift amount of the semi-transmissive film refers to the phase difference between the light transmitted through the transparent substrate and the light transmitted through the semi-transmissive film. The phase shift amount is "90 degrees or less", which means that if the angle is expressed in radians, the phase difference is "(2n-1/2) π~(2n+1/2)π (where n is an integer)" .

As the exposure light used for the transfer, it is preferable to include a wavelength region including i-rays, h-rays, and g-rays. Thereby, even if the area of the transfer target becomes large (for example, a square having a side of 300 mm or more), exposure can be performed without lowering the production efficiency. The representative wavelength of the exposure light may be any one of an i-ray, an h-ray, and a g-ray, and may be, for example, a g-ray. Preferably, the transmittance and the phase shift amount are sufficient with respect to any of the i-ray, the h-ray, and the g-ray.

A known one can be used for an etchant (etching liquid or etching gas) used for each film material. In the case of a film containing a Cr or Cr compound (for example, a Cr light-shielding film and having an antireflection layer using a Cr compound on the surface), an etching solution containing ammonium cerium nitrate known as an etchant for chromium can be used. Further, for a film containing a Cr or Cr compound, dry etching using a chlorine-based gas can also be applied.

Further, for the film of MoSi or a compound thereof, an etching solution obtained by adding an oxidizing agent such as hydrogen peroxide, nitric acid or sulfuric acid to a fluorine compound such as hydrofluoric acid, hydrazine hydrofluoric acid or hydrofluoroammonium can be used. Alternatively, a fluorine-based etching gas may be used for the film of MoSi or a compound thereof.

Further, in the case of forming a pattern using the film materials, it is preferable to use wet etching in the step of etching the pattern. Further, it is more preferable to use wet etching in all etching steps.

Next, a photomask which can be used in the manufacturing method of the electronic device of the present invention will be described. The photomask of the present invention is used for manufacturing a laminated structure in which a first thin film pattern obtained by patterning a first thin film and a second thin film patterned by patterning a second thin film are laminated on the same substrate. A reticle for an electronic device. The photomask of the present invention is provided for being transparent A first transfer pattern of the first thin film pattern in which the formed semi-transmissive film and the light-shielding film are patterned is formed on the substrate. Here, the first transfer pattern has a shape for forming the first thin film pattern of the electronic device by exposure, and includes no image formation by the exposure device used in the exposure. The line width mark pattern. In the photomask of the present invention, in order to form the second transfer pattern for forming the second thin film pattern of the electronic device, one of the first transfer patterns defined by the mark pattern may be partially borrowed Removed by additional processing. Since the photomask of the present invention can be removed by additionally processing a part of the first transfer pattern, it can be preferably used in a method of manufacturing an electronic device of the present invention including additional processing of the first transfer pattern. .

Preferably, the second transfer pattern includes a light-transmitting portion surrounded by the semi-transmissive portion, a light-transmitting portion surrounded by the light-shielding portion, a semi-transmissive portion surrounded by the light-shielding portion, and a light-shielding portion surrounded by the semi-transmissive portion. Any one of a light shielding portion surrounded by the light transmitting portion and a semi-light transmitting portion surrounded by the light transmitting portion. The second transfer pattern produced by the additional processing of the present invention removes one of the first transfer patterns, and as a result, forms the above-described pattern.

The mark pattern preferably includes a semi-transmissive portion or a light-transmitting portion having a width of 0.3 to 1.5 μm surrounding a portion of the light-shielding portion of the first transfer pattern, and more preferably a semi-transmissive portion having a width of 0.3 to 1.0 μm. Or light transmission part. If the line width of the mark pattern is too large, it causes a problem of resolution and transfer at the time of the first exposure. On the other hand, if the line width of the mark pattern is too small, it is difficult to absorb the alignment error with the first transfer pattern formed on the mask in the drawing step necessary for additional processing. Since the line width of the mark pattern is a specific width as described above, it is possible to avoid defects and difficulties. Further, in the case where the mark pattern includes the semi-transmissive portion sandwiched by the light-shielding portion, it is more preferable that the image is not easily resolved at the time of the first exposure.

The present invention is applicable to a method of manufacturing a display device using the method of manufacturing an electronic device of the present invention. The "display device" includes a liquid crystal display device (LCD), a plasma display (PDP), an organic EL (electroluminescence) display device, and the like. According to the method of manufacturing an electronic device of the present invention, by laminating various conductive films or The insulating film can form an electronic device such as a transistor, a diode, a capacitor, a resistor, or the like with high precision. These electronic devices are applied to semiconductors such as integrated circuits, liquid crystal display devices, organic EL display devices, plasma displays, and the like. Therefore, the manufacturing method of the electronic device of the present invention can be preferably used when manufacturing a display device having the electronic devices.

Further, in the display device (including a liquid crystal display device, a plasma display device, and an organic EL display device), as the pattern is refined, the tendency of arranging the fine patterns in a small area and high density, and the tendency to increase the number of layers become apparent. . Under such circumstances, the industrial significance of the present invention is becoming larger and larger.

[Examples] <Example 1>

Fig. 1 is a view showing an aspect of a reticle which can be used in the method of manufacturing an electronic device of the first embodiment of the present invention. Fig. 1(a) shows a first transfer pattern including the light transmitting portion 11, the semi-transmissive portion 12, and the light shielding portion 13 in the reticle, and a cross section of the one-point chain portion is shown in a plan view. Figure 1 (b).

The photomask shown in FIG. 1 is prepared by sequentially forming a semi-transmissive film 20 and a light-shielding film 30 on the transparent substrate 10, and the semi-transmissive film 20 and the light-shielding film 30 are respectively made of light micro-transistors. The steps are patterned and patterned to form. Therefore, the transparent substrate 10 is exposed in the light transmitting portion 11, and the semi-transmissive portion 12 is formed on the transparent substrate 10 to form the semi-transmissive film pattern 21, and the light shielding portion 13 is formed by laminating the semi-transmissive film pattern 21 and the light shielding film pattern 31. Made.

Furthermore, the order of lamination of the semi-transmissive film 20 and the light-shielding film 30 may be reversed. In this case, the light-shielding film 30 formed on the transparent substrate 10 can be patterned, and the semi-transmissive film 20 can be formed and patterned to produce the photomask of the present invention.

The light shielding film 30 applied to the photomask of the present invention may also have an antireflection layer having an antireflection function on the surface. The same applies to the following examples.

Here, as the transparent substrate 10 constituting the photomask, a quartz glass substrate whose surface is polished is used. The size of the transparent substrate 10 is not particularly limited and may be performed according to the use of the mask. The exposed substrate (for example, a substrate for a flat panel display or the like) is appropriately selected. As the transparent substrate 10, for example, a rectangular substrate having a side of 300 mm or more is used.

Further, in the photomask used in the first embodiment, an anti-reflection layer in which Cr is used as a material and having Cr oxide on its surface is used as the light-shielding film 30, and as a raw material of the semi-transmissive film 20, MoSi is used. . That is, the light-shielding film 30 and the semi-transmissive film 20 have etching selectivity with each other, and the other is resistant to the etchant (etching liquid or etching gas) of one film, and is suitable for the manufacture of the photomask of FIG. When there is no etch selectivity with respect to each other, an etch stop film may be provided between the two films.

Fig. 1(c) shows a distribution of transmitted light amount on a point chain line shown in Fig. 1(a) when the photomask of the present invention shown in Fig. 1(a) is placed on an exposure apparatus and irradiated with exposure light. The resist film on the transfer target receives irradiation according to the amount of light of the distribution. The horizontal dashed line shown in Fig. 1(c) indicates the threshold value of the photosensitivity of the resist material. The same is true in the following examples.

Hereinafter, a procedure for manufacturing the electronic device of the first embodiment using the photomask will be described with reference to Figs. 1 to 4 .

Fig. 2 is a view showing a first film pattern forming step performed on a transfer target. Here, in the TFT array used in the display device, a layer and a source connecting the pixel electrodes are formed. The contact hole 90 of the layer of the drain electrode (refer to FIG. 4(c)). However, the present invention is not limited to this application, and can be applied to the contact hole 90 connecting the upper layer side and the lower layer side in the wiring of the multilayer structure.

The contact hole 90 may have a diameter of about 1.5 to 5 μm, and is formed by opening a hole of an insulating layer (for example, a passivation layer) of an electronic device to be obtained with a diameter of 2.5 μm. Also, in the source. Bungee jumping. The layer is designed to have a substantially square connection portion having a side of 7 μm and a wiring portion connected thereto, and the contact hole 90 is disposed at the center of the connection portion. Further, the effect of the present invention is remarkable when the size of the connecting portion is in the range of about one side of about 3 to 10 μm.

As shown in FIG. 2(a), first, a first resist film 40a is formed on the first film 60 formed on the substrate 50 (hereinafter also referred to as "device substrate 50"). The first resist film 40a is a positive type Resist. Then, the first resist film 40a is exposed by using the photomask shown in FIG. 1, and the first transfer pattern is transferred. As an exposure apparatus for exposure, an exposure apparatus for an LCD is used, and a light source including a wavelength region of an i-ray to a g-ray is used. Next, development of the first resist film 40a (top view of Fig. 2 (b-1) and sectional view of Fig. 2 (b-2)) is performed. Here, a resist pattern 41a having a different resist residual film value is obtained in a region corresponding to the semi-transmissive portion 12 of the mask and a region corresponding to the light shielding portion 13. Then, the resist film 41a is used as an etching mask to etch the first film 60 (Fig. 2(c)). That is, only the portion remaining in the resist remains, and the first film 60 is removed to form the first film pattern 61. The first thin film pattern 61 has a shape including a connecting portion of an electronic device to be obtained. The first resist pattern 41a is peeled off (Fig. 2 (d-1) plan view, (d-2) cross-sectional view).

Next, the second film 70 is formed on the entire surface of the device substrate 50 including the obtained first film pattern 61 (the plan view of Fig. 4 (a-1) and the cross-sectional view of Fig. 4 (a-2)). Here, the second film 70b of a photosensitive (negative) material is used as the second film 70.

Then, the second thin film 70b is patterned to form the second thin film pattern 71b. That is, the first transfer pattern is exposed to the second thin film 70b by using the photomask of FIG. 3 (same as the photomask of FIG. 1). The exposure device used can be the same as described above. Then, as shown in FIG. 4 (b-1) and FIG. 4 (b-2), the amount of light is adjusted so that the second film 70b in the region corresponding to the light shielding portion 13 of the mask is in a hollow pattern. Thereby, the second thin film pattern 71b (contact hole pattern) having a fine diameter (about 1.5 to 5 μm) is formed in the second thin film 70b.

In the above description, the case where the second film 70 is photosensitive (negative type) has been described. However, in the case of the second film 70 including a material having no photosensitivity, the second film 70 may be applied to the second film 70. A second resist film (negative type) is formed, and after the second resist film is patterned, the second resist film is etched using the obtained resist pattern as a mask to form a second thin film pattern.

As is clear from the above, the patterning of the first film 60 and the second film 70 is the same as that of the patterns for forming mutually different shapes, but the same mask is used. That is, the same transfer pattern is used for the second exposure, but the conditions of the film formation step are not In the same way, the pattern of the contact portion and the hole pattern can be formed on different layers.

Here, it is assumed that the first transfer pattern in the photomask has a case where the offset component is generated in the manufacturing step (specifically, the drawing step). In other words, the first transfer pattern may not completely match the two-dimensional pattern developed on the ideal coordinates indicated by the drawing material. However, in any of the coordinates on the first transfer pattern, even if there is an offset component from the ideal ideal coordinate, the coordinates are only in the same direction in the first thin film pattern 61 and the second thin film pattern 71. The same amount of offset is produced so that no overlap offset occurs between them.

In addition, the first transfer pattern is a mask including the light shielding portion 13, the semi-transmissive portion 12, and the light transmitting portion 11, and in the manufacturing step, drawing is required twice. It is expected that the pattern (in particular, the semi-transmissive film pattern 21 and the light-shielding film pattern 31) which is suppressed from being drawn in the two drawing steps is overlapped with each other. That is, it is preferable that the edges of the semi-transmissive portion 12 and the light-shielding portion 13 are defined by one drawing step. A method of manufacturing such a mask will be described below.

According to the above, an electronic device in which the superposition accuracy of the first thin film pattern 61 and the second thin film pattern 71 is extremely high can be manufactured (FIG. 4(c)).

<Example 2>

In the second embodiment, in the same manner as in the first embodiment, the first film 60 and the second film 70 were patterned using the same mask to form the same electronic device as in the first embodiment. However, the shape of the first transfer pattern of the photomask and the photosensitivity of the first resist and the second film 70 formed on the transfer target are different from those of the first embodiment.

As the first transfer pattern of the photomask used here, the one shown in FIG. 5 (which is the same as the photomask of FIG. 7 described later) is used. Fig. 5(a) is a plan view, Fig. 5(b) is a cross-sectional view, and Fig. 5(c) is a view showing a transmitted light amount distribution of exposure light.

Similarly to the photomask of the first embodiment, the mask shown in FIG. 7 is prepared by sequentially forming a mask substrate having a semi-transmissive film 20 and a light-shielding film 30 on the transparent substrate 10, and the semi-transmissive film 20 is formed. And the light shielding film 30 is formed by patterning by a photolithography step, respectively. Therefore, in the light transmitting portion 11 The transparent substrate 10 is exposed, and the semi-transmissive portion 12 is formed by forming the semi-transmissive film pattern 21 on the transparent substrate 10. The light-shielding portion 13 is formed by laminating the semi-transmissive film pattern 21 and the light-shielding film pattern 31.

Further, the order of lamination of the semi-transmissive film 20 and the light-shielding film 30 may be the same as in the first embodiment. The raw materials of the light shielding film 30 and the semi-transmissive film 20 are also the same as in the first embodiment.

The procedure for manufacturing the electronic device of the second embodiment using the photomask will be described with reference to Figs. 5 to 8 . The first thin film pattern 61 and the second thin film pattern 71 to be formed are the same as those in the first embodiment. In addition, the case where it is the same as that of the first embodiment is also omitted in the step.

Fig. 6 is a view showing a first film pattern forming step performed on a transfer target.

As shown in FIG. 6(a), first, a first resist film 40b is formed on the first film 60 formed on the device substrate 50. The first resist film 40b is a negative resist. Then, the first resist film 40b is exposed by using a photomask shown in FIG. 5, and the first transfer pattern is transferred. The exposure apparatus was the same as that of the first embodiment.

Next, development of the first resist film 40b is performed (FIG. 6 (b-1) plan view and FIG. 6 (b-2) cross-sectional view). Here, the first resist pattern 41b having a different resist residual film value is obtained in a region corresponding to the semi-transmissive portion 12 of the mask and a region corresponding to the light transmitting portion 11. Then, the first resist film 41b is used as an etching mask to etch the first film 60 (FIG. 6(c)). That is, only the portion remaining in the resist remains, and the first film 60 is removed to form the first film pattern 61. The first thin film pattern 61 has a shape including a connecting portion of an electronic device to be obtained. The first resist pattern 41b is peeled off (FIG. 6 (d-1) plan view and FIG. 6 (d-2) cross-sectional view).

Next, the second film 70 is formed on the entire surface of the device substrate 50 including the obtained first film pattern 61 (the plan view of FIG. 8 (a-1) and the cross-sectional view of FIG. 8 (a-2)). Here, the second film 70a of a photosensitive (positive) material is used as the second film 70.

Then, the second thin film 70a is patterned to form the second thin film pattern 71a. That is, the first transfer pattern is exposed to the second thin film 70a by using the photomask of FIG. 7 (same as the photomask of FIG. 5). The exposure apparatus used is the same as described above. Further, as shown in FIGS. 8(b-1) and 8(b-2), the second film 70a in the region corresponding to the light shielding portion 13 of the mask is in a hollow pattern.

Further, in the same manner as in the first embodiment, when the second film 70 does not have a photosensitive material, the second resist film (positive type) may be formed on the second film, and the second resist may be formed. After the etching of the etching film, the obtained resist pattern is used as a mask to etch the second film to form a second film pattern.

As is apparent from the above, in the second embodiment, the patterning of the first film 60 and the second film 70a is the same as that of the patterns for forming mutually different shapes, but the same mask is used. Therefore, an electronic device having extremely high superimposition accuracy between the first thin film pattern 61 and the second thin film pattern 71a can be manufactured (FIG. 8(c)).

<Reference example>

Further, the photomasks used in the first embodiment and the second embodiment include a transfer pattern including the light shielding portion 11, the semi-transmissive portion 12, and the light transmitting portion 11 (see FIGS. 1(a) and 5( a)), such as a multi-gray mask. In the process of manufacturing such a photomask, as described above, patterning is performed by applying a photolithography step to each of the semi-transmissive film and the light-shielding film formed on the substrate. However, if a positional shift occurs in the drawing step in the secondary photolithography method, there is a risk that the mask itself becomes an alignment error component EM.

In this regard, the inventors have found that a multi-gray reticle that does not cause mutual positional shift in the secondary photolithography step can be manufactured by the following method.

A method for manufacturing a mask without misalignment error is a method for manufacturing a mask, which is characterized in that a layered film and an upper film are patterned by laminating layers having different exposure light transmittances to form an underlayer film pattern and a method for producing a mask for a transfer pattern provided on an upper substrate; and a step of: preparing the underlayer film and the upper film including a material having etching selectivity from each other on the transparent substrate; Further, a mask base on which the first resist film is formed is formed, and by forming the first resist film for the first time, a region for forming the upper film pattern and defining the underlying film pattern is formed. The first resist of the tentative pattern a first etching step of etching the upper layer film by using the first resist pattern as a mask; forming a second resist film on the entire surface including the formed upper layer film pattern and the tentative pattern; a second resist pattern for forming the underlying film pattern is formed by drawing the second resist film a second time, and a second etching step is performed to form the tentative pattern and the second resist pattern The lower layer film is etched as a mask; and the third etching step is performed by etching and removing the tentative pattern by using the second resist pattern as a mask.

More specifically, the mask manufacturing method 1 of the above-described misalignment error can be used as the mask manufacturing method 2 of the following misalignment error.

A method of manufacturing a mask without alignment error, comprising a method of manufacturing a mask comprising a light-shielding portion, a semi-transmissive portion, and a transfer pattern of a light-transmitting portion; The method includes the steps of: preparing a semi-transmissive film and a light-shielding film including a material having etching selectivity from each other on a transparent substrate, and further forming a photomask substrate having a first resist film; The first drawing of the film is performed to form the light-shielding portion and the first resist pattern defining the tentative pattern of the semi-transmissive portion. The first etching step is performed by using the first resist pattern as the first resist pattern. Etching the light-shielding film; forming a second resist film on the entire surface including the formed light-shielding portion and the tentative pattern; and forming the second resist film for the second time To form the above a second resist pattern of the semi-transmissive portion; a second etching step of etching the semi-transmissive film by using the tentative pattern and the second resist pattern as a mask; and a third etching step The second resist pattern is etched and removed as a mask to remove the tentative pattern.

Further, in the above two methods (mask manufacturing methods (1) and (2) for non-alignment errors), it is more preferably as follows.

(1) in the second resist pattern forming step, the second drawing is performed such that one of the tentative patterns is exposed from an edge of the second resist pattern, and the tentative pattern is removed in the etching step The tentative pattern in a state in which a part of the edge of the second resist pattern is exposed is subjected to wet etching.

(2) The width of the tentative pattern is set to 2 μm or less.

(3) The transfer pattern is a hole pattern or a dot pattern.

(4) In the second resist pattern forming step, the second drawing is performed such that the edge of the light-transmitting portion side of the tentative pattern is exposed to a width of 0.1 to 1.0 μm.

An embodiment of a method of manufacturing a reticle will be described with reference to Figs. 19 and 20 .

The transfer pattern of the photomask formed here may be as shown in FIG. In order to evaluate whether or not the mutual alignment error of the light-shielding portion and the semi-transmissive portion (and, as a result, the light-transmitting portion as a result) included in the transfer pattern is generated, the size of D1 and D2 shown in FIG. 21 can be used. Make a decision. In the following reference embodiment, FIG. 21(A) is shown, that is, the transfer of the light-shielding portion including the semi-transmissive portion surrounded by the light-transmitting portion and the light-shielding portion surrounded by the semi-transmissive portion is produced without generating an alignment error. Use the method of pattern.

In FIGS. 19 and 20, a case where the semi-transmissive portion is formed as the underlayer film pattern and the light-shielding portion is formed as the upper layer film pattern will be described as an example. Moreover, in Fig. 19 and Fig. 20, The upper side shows a plan view and the lower side shows a cross-sectional view. Further, when the resist film is located at the uppermost layer, it is schematically drawn so as to be visible through the light-shielding film which is hidden underneath.

First, as shown in FIGS. 19(A) to (C) and FIG. 20(D), the first photolithography step of patterning the light shielding film is performed.

In FIG. 19, first, a semi-transmissive film and a light-shielding film are sequentially laminated on a transparent substrate, and a photomask substrate on which a first resist film (here, a positive resist is included) is formed thereon ( Refer to Fig. 19(A)). Here, the semi-transmissive film and the light-shielding film have etching selectivity with each other. That is, the light shielding film is resistant to the etchant of the semi-transmissive film, and the semi-transmissive film is resistant to the etchant of the light shielding film. Furthermore, the specific raw materials can be set as described above.

Next, the first resist pattern is formed by performing the first drawing and developing. The first resist pattern defines a region of the light shielding portion. Further, in a region to be a semi-transmissive portion, a portion for forming a tentative pattern including a light-shielding film on the outer edge of the semi-transmissive portion is also included in the first resist pattern (see FIG. 19(B). ).

The tentative pattern is removed by etching in a subsequent step. Preferably, it is preferably removed by wet etching which is excellent in the action of isotropic etching. Therefore, it is expected that the width of the tentative pattern is set to a width that can be surely removed without excessive time in the removal step. Specifically, it is preferably a width of 2 μm or less.

Further, the tentative pattern is set to absorb the alignment offset amount derived from the second drawing step. Therefore, it is desirable to determine based on the magnitude of the alignment offset that may be generated. Therefore, if the maximum value of the alignment offset is ±0.5 μm, the width of the provisional pattern is preferably 0.5 to 2 μm, more preferably 0.5 to 1.5 μm, and still more preferably 0.5 to 1.0 μm.

Further, since the first resist pattern includes the portion where the light shielding portion is formed and the portion where the tentative pattern is formed as described above, the drawing material at the time of the first drawing is determined based on this.

As described above, the etching step (the third etching step) for removing the tentative pattern is appropriately determined by the width of the tentative pattern (for example, 2 μm or less) according to the maximum value of the alignment offset. In the case of the step, the production of an efficient photomask can be realized without undue time or effort.

Next, the first resist pattern is used as an etching mask to etch the light shielding film (first etching). Here, the area of the light-shielding portion is defined, and the outer edge of the semi-transmissive portion patterned thereafter is defined by a tentative pattern (see FIG. 19(C)). Next, proceeding to Fig. 20, the first resist pattern is peeled off (see Fig. 20(D)). By the above, the first photolithography step of patterning the light shielding film is completed.

Next, a resist film is applied again on the entire surface of the substrate (see FIG. 20(E)). Then, the second drawing and development are performed to form a second resist pattern (see FIG. 20(F)). This second resist pattern exposes a portion that becomes a light transmitting portion.

The second resist pattern is formed by a drawing step different from the drawing step in forming the first resist pattern, so that it is substantially impossible to shift the position with respect to the position of the first resist pattern. Set to zero. However, according to the present invention, regardless of how the alignment changes, the offset from the design value can be made zero in the resulting final transfer pattern.

In other words, in the second resist pattern, the region which becomes the light transmitting portion is exposed, and the region which becomes the semi-light transmitting portion is covered, and as a result, the portion which becomes the boundary between the semi-light transmitting portion and the light transmitting portion is semi-transparent. The side of the portion is a resist pattern having a size smaller than a predetermined marginal size (for example, 0.1 to 1.0 μm, more preferably 0.2 to 0.8 μm). That is, the edge of the resist pattern is retracted toward the semi-transmissive portion side (the left side in the cross section J-J of FIG. 20(F)). Therefore, the edge of the light-transmitting portion side of the tentative pattern (or at least the side surface on the side of the light-transmitting portion) is slightly exposed from the edge of the second resist pattern (see FIG. 20(F)).

Therefore, the drawing materials in consideration of this aspect are used in the second drawing. For example, the second resist pattern can be formed by designing the edge of the resist pattern to be at the center of the width of the tentative pattern.

Thus, by exposing the edge of the light transmitting portion side of the tentative pattern to a specific width (for example, 0.1 to 1.0 μm), the alignment deviation between the different photolithography steps can be surely absorbed. The shifting, and in the etching step (the third etching step) of removing the tentative pattern, may not require excessive time or effort.

The edge of the light-transmitting portion side of the tentative pattern is a portion of the exact outer edge of the semi-transmissive portion defined by the first etching step. Therefore, the portion is used as an etching mask for the second time. The resist pattern is used, and the semi-transmissive film is etched (second etching) using an etchant of a semi-transmissive film (see FIG. 20(G)). Here, since the tentative pattern is formed by the light shielding film, it does not disappear even if it contacts the etchant of the semi-transmissive film.

Next, in a state in which the second resist pattern remains, the tentative pattern is removed using an etchant of the light-shielding film (third etching step). Further, since the formed light shielding portion is protected by the second resist pattern, it is not damaged when the tentative pattern is removed. Here, since it is effective to perform side etching from the side surface of the tentative pattern, it is preferable to use wet etching which is excellent in the action of isotropic etching instead of dry etching. Then, the tentative pattern disappears. At this time, since the semi-transmissive film is resistant to the etchant of the light-shielding film, it does not disappear (see FIG. 20(H)). Then, the second resist pattern is finally peeled off (see FIG. 20(I)).

As described above, the photomask obtained by the steps shown in FIGS. 19 and 20 is provided with a light shielding portion at the center of the semi-transmissive portion as designed. In other words, the previous defects in which the edges of the light-shielding film pattern and the semi-transmissive film pattern formed in the different drawing steps are shifted in the X direction and the Y direction are not generated, and the position is designed as it is.

At the time of the second drawing, even if a positional shift with respect to the first drawing is generated, at least a part of the tentative pattern is exposed from at least a part of the edge of the second resist pattern. In other words, even when the relative positional shift occurs, the size of the tentative pattern is selected such that the side surface of the tentative pattern is exposed from the edge of the second resist pattern. Therefore, the outer edge of the semi-transmissive portion can be surely defined by the tentative pattern, so that the design of the first resist pattern can be realized as it is. Further, since the light-shielding portion is protected by the second resist pattern, the tentative pattern can be etched and removed (the third etching step) without affecting the semi-transmissive portion due to the etching selectivity, so that it is not necessary to remove the tentative pattern. Light lithography steps. Furthermore, in order to remove the tentative pattern, the photolithography step can be repeated again.

As described above, in the present invention, it is possible to accurately align the respective regions of the transfer pattern in the mask which requires a plurality of times of drawing, and further, the number of times of performing the photolithography step can be suppressed. A method of manufacturing a photomask having a transfer pattern.

Further, one of the tentative patterns is formed so as to be exposed from the edge of the second resist pattern, and the tentative pattern which is partially exposed can be removed by the action of isotropic etching by wet etching. Therefore, the number of times of performing the photolithography step can be surely suppressed.

In the present invention, the first transfer pattern of the multi-gray masks described in the first and second embodiments can be formed by the method described in the above Reference Example. In this case, the edges of the light-shielding portion and the semi-transmissive portion included in the first transfer pattern are all defined by the first drawing. As a result, it is possible to provide a method of manufacturing a photomask including a transfer pattern in which the alignment of each region of the transfer pattern is accurately performed and the number of times of the photolithography step is suppressed.

<Example 3>

Fig. 9 is a view showing an example of a photomask used in the step of manufacturing the optical device of another embodiment of the present invention.

The photomask includes a first transfer pattern in which the semi-transmissive film 20 is formed on the transparent substrate 10, and the mask base of the light-shielding film 30 is formed and the light-shielding film 30 is patterned. Obtained. The film raw material was the same as in Example 1.

The first transfer pattern is used to form the first thin film pattern 61, and forms a source. On the other hand, the connection portion in the layer of the drain layer can be used as the second transfer pattern for forming the second film pattern 71 by performing additional processing after forming the first thin film pattern 61.

The first transfer pattern includes a light shielding portion 13 and a semi-light transmitting portion 12 . Further, in the region of the light shielding portion 13, a slit-shaped semi-transmissive portion having a fine width (here, a width of 1 μm) is formed. 12 (marker pattern 80), there is a light-shielding portion 13 surrounded by the slit-shaped semi-transmissive portion 12 (Fig. 9 (a) top view, (b) cross-sectional view). In the present aspect, the slit-shaped semi-transmissive portion 12 has a shape corresponding to the outer circumference of the contact hole pattern of the electronic device to be obtained, and a quadrangle such as a pattern surrounding the contact hole pattern is formed with a width of 1 μm.

The mark pattern 80 is formed as a semi-transmissive portion, but may be formed as a light-transmitting portion. The former is better in terms of being difficult to solve.

Hereinafter, the steps of manufacturing the electronic device of the third embodiment which is the same as that of the first embodiment will be described using Figs. 9 to 12. However, it differs from the first embodiment in that it is used for the second thin film pattern forming step by performing additional processing on the photomask used in the first thin film pattern forming step.

Fig. 10 shows a first film pattern forming step. As shown in FIG. 10(a), first, a first resist film 40a is formed on the first film 60 formed on the device substrate 50. The first resist film 40a is a positive resist. Then, the first resist film 40a is exposed using a photomask shown in FIG. 9, and the first transfer pattern is transferred. The exposure apparatus can be the same as that of Embodiment 1, but it is preferable to increase the amount of illumination light to the reticle by extending a certain amount of exposure time. Next, development of the first resist film 40a is performed (FIG. 10 (b-1) plan view and FIG. 10 (b-2) cross-sectional view).

Here, since the amount of irradiation light is increased, the first resist film 40a in the region corresponding to the semi-transmissive portion 12 of the mask is sufficiently sensitized and eluted by development. On the other hand, the first resist film 41a in the region corresponding to the light shielding portion 13 forms the first resist pattern 41a in which the specific residual film remains. Further, since the semi-transmissive portion 12 having a width of 1 μm is a line width equal to or lower than the resolution limit of the exposure apparatus, the first resist film 40a can hardly be film-reduced, and thus the transfer is not substantially performed.

Then, the first resist film 41a is used as an etching mask to etch the first film 60 (Fig. 10(c)). That is, only the portion where the resist remains is left, and the first film 60 is removed to form the first film pattern 61. The first thin film pattern 61 has a shape including a connecting portion of an electronic device to be obtained. The first resist pattern 41a is peeled off (Fig. 10 (d-1) plan view, (d-2) cross-sectional view).

Next, the second film 70 is formed on the entire surface of the device substrate 50 including the obtained first film pattern 61 (a plan view of FIG. 12 (a-1) and a cross-sectional view of FIG. 12 (a-2)). Here, the second film 70a of a photosensitive (positive) material is used as the second film 70.

Then, the second thin film 70a is patterned to form the second thin film pattern 71a. At this time, the mask of Fig. 11 obtained by performing additional processing on the mask of Fig. 9 was used. This additional processing removes the light shielding portion 13 located at a position surrounded by the slit-shaped semi-transmissive portion 12 formed into a fine width, and converts it into the light transmitting portion 11. That is, the light-shielding film 30 which forms the light-shielding portion 13 surrounding the slit-shaped semi-transmissive portion 12 is removed by etching, and the semi-transmissive film 20 thus exposed is also removed by etching. Then, the light transmitting portion 11 in which the transparent substrate 10 is exposed is formed. The light transmitting portion 11 has a shape and a size for forming a hole pattern in the electronic device. Furthermore, the details of the additional processing process will be described below.

The first transfer pattern of the reticle of FIG. 9 is converted into the second transfer pattern of the reticle of FIG. 11 by the above-described additional processing. However, since the edge of the light-shielding portion 13 in the second transfer pattern exists at the edge of the first transfer pattern (including the edge of the semi-transmissive portion 12 adjacent to the fine width), the second transfer pattern The edge of the pattern (especially the edge of the light-shielding portion 13) is not the edge that is reformed during the above-described conversion.

When the second transfer pattern is transferred to the second film 70a, the same exposure method as described above can be used. Further, as shown in (b-1) and (b-2) of FIG. 12, the amount of light is adjusted so that the second thin film 70a in the region corresponding to the light transmitting portion 11 of the mask is in a hollow pattern. Thereby, the second thin film pattern 71a (contact hole pattern) is formed.

In the above, the case where the second film 70 is photosensitive (positive type) has been described. However, when the second film 70 including a material having no photosensitivity is included, the second film 70 can be formed on the second film 70. The second resist film (positive type) is subjected to a photolithography step, which is the same as in the first embodiment.

As is clear from the above, the patterning of the first film 60 and the second film 70 is used to pattern the patterns of mutually different shapes. Still, the light used for the patterning The transfer pattern on the cover is converted by additional processing, and is a transfer pattern defined by only one photolithography step (that is, one drawing step). Therefore, even if the first transfer pattern of the photomask includes the drawing offset component generated in the manufacturing step (drawing step), the component is also the same in the first thin film pattern 61 and the second thin film pattern 71, and thus does not An alignment error due to overlap is generated.

As a result, an electronic device having extremely high overlap accuracy between the first thin film pattern 61 and the second thin film pattern 71 can be manufactured (FIG. 4(c)).

<Example 4>

The additional processing of the photomask performed in the third embodiment will be described as the fourth embodiment.

Fig. 13 ((a-1) plan view and (a-2) cross-sectional view) are the photomasks having the first transfer pattern used in the third embodiment. After the first thin film pattern forming step, it is necessary to remove the light-shielding film of the light-shielding portion 13 (hereinafter, also referred to as a removal pattern) surrounded by the mark pattern including the semi-transmissive portion having a fine width, and the semi-transparent light on the lower layer side thereof. membrane. This step can be carried out as follows.

First, a resist is applied to the entire surface of the transparent substrate 10 including the first transfer pattern to form an additional processing resist film 45 (FIG. 13 (b-1) plan view and (b-2) cross-sectional view). Then, by drawing and developing using a drawing machine, the removed pattern portion is exposed, and an additional processing resist pattern 46 covering the light shielding portion 13 other than the above is formed (FIG. 13(c)).

In this case, as the drawing pattern, it is necessary to surely cover the light shielding portion 13 of the portion other than the removal pattern. However, even if the edge position of the additional processing resist pattern 46 is the same as the size of the light shielding portion 13 except the removal pattern, the same transparent substrate 10 on which the first transfer pattern has been drawn is formed. Since the depiction is repeated, there is a risk that the edge positions are inaccurately coincident due to the mutual offset due to the overlap. When the offset occurs at the edge position, the light-shielding portion 13 other than the removal pattern (that is, the edge of the light-shielding portion 13 in the second transfer pattern) may be partially exposed from the additional processing resist pattern 46. Dissolved during etching.

Therefore, the drawing data is adjusted such that the edge position of the additional processing resist pattern 46 formed is in the region of the slit-shaped semi-transmissive portion 12 having a fine width. In addition, since the coordinate offset caused by the drawing machine is at most about 0.5 μm, if the semi-transmissive portion 12 having a fine width has a width of 1 μm, the edge of the additional processing resist pattern 46 can be reliably positioned in the half. The line width of the light transmitting portion 12 (marking pattern 80) is within. FIG. 13(c) shows a case where the additional processing resist pattern 46 enters the inside of the semi-transmissive portion 12 having a fine width by a distance d1.

Therefore, as the drawing data, the sizing of the edge of the additional processing resist pattern 46 toward the removal pattern side by 0.5 μm is added (an alignment edge of 0.5 μm is added). In other words, in the portion, the design of the pattern for the second transfer pattern is shifted by about 0.5 μm toward the semi-transmissive portion 12 side of the fine width.

In this way, the removal pattern is surely exposed from the additional processing resist pattern 46, and the light-shielding portion 13 (the light-shielding portion 13 of the second transfer pattern) other than the removal pattern is surely added by the additional processing resist pattern. 46 coverage.

Furthermore, the size of the resizing can be determined in consideration of the size of the coordinate offset component of the drawing machine. However, if the maximum value of the coordinate offset is ±X μm (for example, ±5 μm), the adjustment size may be set to X μm (for example, 5 μm). However, the size is related to the width of the semi-transmissive portion 12 to be formed in the fine width of the first transfer pattern to 2×μm. Further, if the width of the semi-transmissive portion 12 is too large, the line width which can be resolved by the exposure device is approached. Therefore, it is preferable to set it as X to about 0.3-0.8 micrometer here.

Next, the formed additional processing resist pattern 46 is used as an etching mask to remove the removal pattern (FIG. 13(d)). Here, an etchant for a light-shielding film material is used (if the light-shielding film material is a component containing Cr as a main component, it is an etchant for Cr).

Thereafter, etching for removing the exposed semi-transmissive film 20 is performed (Fig. 13(e)). For example, if the semi-transmissive film 20 is made of MoSi as a main component, an etchant for MoSi is used. In this case, it is preferable that the resist pattern for additional processing for etching the light shielding film 30 is not removed. 46, and in this state, only the etchant is changed, and the semi-transmissive film 20 is removed.

At this time, as shown in FIG. 13(e), the edge of the additional processing resist pattern 46 is increased by about 0.5 μm by the above-described resizing, so that the light transmissive portion 11 in the second transfer pattern remains. The risk of a portion of the semi-transmissive film 20. However, if wet etching is applied to the etching of the semi-transmissive portion 12, as shown in FIG. 13(e), the semi-transmissive film 20 is sufficiently etched by the side etching progress. Further, when over-etching is performed, the light-shielding portion 13 for forming a contact hole pattern can be obtained more surely. This implies the possibility of achieving a higher level of the subject matter of the present invention in order to reduce the alignment error of the electronic device to be obtained.

That is, as verified in Embodiments 1 to 3, if the alignment error EM component due to the photomask can be theoretically zero, the alignment error of the finally obtained electronic device can be compressed to an extent not previously considered.

<Example 5>

For the additional processing of the photomask performed in the third embodiment, another embodiment will be described as the fifth embodiment.

Fig. 14 ((a-1) plan view and (a-2) sectional view) are the photomasks having the first transfer pattern used in the third embodiment. After the first film pattern forming step, it is necessary to remove the light-shielding film 13 (hereinafter, also referred to as "removal pattern") surrounded by the mark pattern including the semi-transmissive portion having a fine width, and the semi-transparent film on the lower layer side thereof. Light film. This step can be carried out as follows.

First, in the same manner as in the fourth embodiment, a resist is applied to the entire surface of the transparent substrate 10 including the first transfer pattern to form a resist film 45 for additional processing (Fig. 14 (b-1) plan view, (b) -2) Sectional view). Then, in the same manner as in the fourth embodiment, the removal pattern portion is exposed by drawing and development using a drawing machine, and an additional processing resist pattern 46 covering the light shielding portion 13 other than the above is formed (FIG. 14(c)). .

Next, in the same manner as in the fourth embodiment, the formed additional processing resist pattern 46 is used as an etching mask to remove the removal pattern (FIG. 14(d)). Here, use the light-shielding film material An etchant for the material (if the material of the light-shielding film is mainly composed of Cr, it is an etchant for Cr).

Next, in the additional processing of the photomask of the fifth embodiment, the additional processing resist pattern 46 is peeled off (FIG. 14(e)). Thereafter, the semi-transmissive film 20 is partially removed in order to form the light transmitting portion 11 in the second transfer pattern.

Specifically, as shown in FIG. 14(f), a new additional processing resist film 47 is formed on the entire surface of the photomask, and is further drawn using a drawing machine. In the drawing data, the edge of the additional processing resist pattern 48 is adjusted by 0.5 μm with respect to the edge position of the light-shielding portion 13 of the second transfer pattern (the alignment edge is reduced by 0.5 μm). 14(g)). Thereby, as shown in FIG. 14(g), the edge of the additional processing resist pattern 48 is only receded by the distance d2 from the edge of the light shielding portion 13. When the semi-transmissive film 20 is etched by using the additional processing resist pattern 48 formed in this manner as a mask, the edge of the light-shielding portion 13 formed as the first transfer pattern functions as an etching mask. Only the semi-transmissive film 20 located on the lower layer side is removed, and the hole pattern in the second transfer pattern is accurately formed.

That is, in the fourth embodiment and the fifth embodiment, although the drawing step is increased by the additional processing of the photomask, the alignment error component (EM due to the pattern overlap of the photomask is not generated by the new drawing. )Methods.

<Comparative Example 1>

A method of manufacturing the same electronic device as that of the first embodiment by the prior method will be described with reference to FIGS. 15 and 16.

Fig. 15 (a) is a pattern obtained by patterning the light-shielding film 30 formed on the transparent substrate 10 by a known method, and includes a light-shielding portion 13 (first transfer pattern) including a connection portion. This binary mask is set to Mask A.

Using this, a connection portion is first formed on the device substrate 50. That is, as shown in Fig. 16 (a-1), the first thin film 60 is formed on the device substrate 50, and the first resist film 40a (positive type) is further formed. Then, using Mask A, the first transfer pattern is exposed by the exposure device. Light. The exposure apparatus is the same as the above embodiment. Then, as shown in FIGS. 16(b-1) and (b-2), the first resist film 40a is developed, and the obtained first resist pattern 41a is used as a mask to etch the first film 60 (FIG. 16). (c)).

When the first resist pattern 41a is peeled off, the first thin film pattern 61 having the connection portion shown in FIGS. 16(d-1) and (d-2) is completed.

Next, the second thin film 70a is formed on the entire surface of the device substrate 50 including the first thin film pattern 61. The second film 70a includes a second film 70a having a positive photosensitive material (a plan view of Fig. 18 (a-1) and a cross-sectional view of Fig. 18 (a-2)).

Then, exposure is performed by an exposure device using the second mask (Mask B) shown in FIG. The Mask B is a binary mask having a second transfer pattern for forming a hole pattern.

When development is performed after the exposure, the contact hole 90 is formed in the second film 70a (Fig. 18 (c)).

However, Mask A and Mask B are masks formed in different steps, respectively, and even if the same drawing machine is used, the tendency of the coordinate shift generated in the photolithography step (especially the drawing step) performed at the time of manufacture is used. It will not be exactly the same. Fig. 18(c) shows a case where Δx is generated in the x direction and a coordinate shift of Δy is generated in the y direction.

For example, if any of the coordinates on the first transfer pattern that Mask A has is offset from the position of the design coordinate by +M μm and the position of Mask B is shifted to -M μm, the alignment is generated as the overlap. The error is 2M μm. That is, in the electronic device manufactured by this method, the EM component caused by the alignment error of the overlap of the two patterns cannot be prevented from deteriorating the accuracy of the electronic device (FIG. 18(c)).

10‧‧‧Transparent substrate

11‧‧‧Transmission Department

12‧‧‧ semi-transmission department

13‧‧‧Lighting Department

15‧‧‧ alignment mark

21‧‧‧ Semi-transparent film pattern

31‧‧‧Shade film pattern

Claims (20)

A method of manufacturing an electronic device, comprising: forming a first thin film pattern by using a first film formed on a substrate or a first resist formed on the first film Forming the first thin film by the first photolithography step of the first exposure of the photomask; and forming the second thin film pattern forming step on the second thin film formed on the substrate The second resist film on the second film is subjected to a second photolithography step using the second exposure of the second photomask, and the second thin film is patterned into a shape different from the first thin film pattern; 1 that the photomask has a first transfer pattern, and the second photomask is the same photomask as the first photomask, or the second photomask has the first photomask of the first photomask The transfer pattern is subjected to additional processing to form a second transfer pattern. A method of manufacturing an electronic device, comprising the steps of: forming a first film on a substrate; and forming a first film pattern by the first film or the first film formed on the first film The resist film is formed by patterning the first thin film by using a first photolithography step of the first exposure using the first photomask, and forming a second thin film on the substrate on which the first thin film pattern is formed; And the second thin film pattern forming step of performing the second photolithography step including the second exposure using the second photomask on the second thin film or the second resist film formed on the second thin film Patterning the second film into a shape different from the first film pattern; The first photomask has a first transfer pattern, and the second photomask is the same photomask as the first photomask, or the second photomask has the above-described first photomask The first transfer pattern is subjected to additional processing to form a second transfer pattern. The method of manufacturing an electronic device according to claim 1, wherein the first transfer pattern and the second transfer pattern are formed from a semi-transmissive film formed on a transparent substrate and a light shielding film. The method of manufacturing an electronic device according to claim 3, wherein the second transfer pattern includes a light transmitting portion, a light blocking portion, and a semi-light transmitting portion. The method of manufacturing an electronic device according to claim 3, wherein the first transfer pattern includes a light transmitting portion, a light blocking portion, and a semi-light transmitting portion. The method of manufacturing an electronic device according to claim 4 or 5, wherein the edges of the light shielding portion and the semi-transmissive portion included in the first transfer pattern are defined by a single drawing step. The method of manufacturing an electronic device according to claim 4 or 5, wherein in the second thin film pattern forming step, any one of a resist film, a resist process, and an exposure condition used is applied to the first film. The pattern forming step is a different condition. The method of manufacturing an electronic device according to claim 4 or 5, wherein the first film or the first resist film has different photosensitivity from the second film or the second resist film. The method of manufacturing an electronic device according to claim 4 or 5, wherein the first film or the first resist film comprises a positive photosensitive material, and the second film or the second resist film is a negative photosensitive material. The method of manufacturing an electronic device according to claim 4 or 5, wherein the first film or the first resist film contains a negative photosensitive material, and the second film or the second resist film is a positive photosensitive material. The method of manufacturing an electronic device according to any one of claims 4 to 5, wherein the second light is The second transfer pattern included in the cover is formed by performing the additional processing on the first transfer pattern included in the first mask, and the additional processing is performed by removing the first transfer pattern. A part of the second transfer pattern is formed. The method of manufacturing an electronic device according to claim 11, wherein the first transfer pattern has a mark pattern of a line width which is not resolved by an exposure device used for exposure using the first photomask. A method of manufacturing a photomask, comprising: forming a first thin film pattern formed by patterning a first thin film on a same substrate; and patterning the second thin film An electronic device having a laminated structure of a thin film pattern; wherein the photomask has a transfer pattern including a light shielding portion, a semi-transmissive portion, and a light transmitting portion formed on the transparent substrate; and the method for manufacturing the photomask includes the following steps a step of sequentially forming a mask substrate having a semi-transmissive film and a light-shielding film on a transparent substrate; and forming a first resist film formed on the light-shielding film for the first time, thereby forming a step of forming the light-shielding portion and the first resist pattern defining the tentative pattern of the semi-transmissive portion; and in the first etching step, etching the light-shielding film by using the first resist pattern as a mask; a step of forming a second resist film on the entire surface of the formed light-shielding portion and the tentative pattern; and forming the semi-transmissive portion by performing second drawing on the second resist film The second resist pattern a second etching step of using the tentative pattern and the second resist pattern as The semi-transmissive film is etched by the mask; and the third etching step is performed by etching and removing the tentative pattern by using the second resist pattern as a mask. The method of manufacturing a reticle according to claim 13, wherein the transfer pattern includes a light-transmitting portion surrounded by the semi-transmissive portion, a light-transmitting portion surrounded by the light-shielding portion, and a semi-transmissive portion surrounded by the light-shielding portion, and a half Any one of a light shielding portion surrounded by the light transmitting portion, a light shielding portion surrounded by the light transmitting portion, and a semi-light transmitting portion surrounded by the light transmitting portion. A method of manufacturing a photomask, comprising: forming a first thin film pattern formed by patterning a first thin film on a same substrate; and patterning the second thin film An electronic device having a laminated structure of a thin film pattern; wherein the photomask includes a first transfer pattern for forming the first thin film pattern on a transparent substrate; and the method for manufacturing the photomask includes the following steps: a step of sequentially forming a mask base of the semi-transmissive film and the light-shielding film on the transparent substrate; and a first transfer pattern forming step of forming the semi-transmissive film and the light-shielding film by using a photolithography step The first transfer pattern; the first transfer pattern having a shape for forming the first thin film pattern of the electronic device by exposure and including exposure by the exposure The marking pattern of the line width which is not resolved by the device, wherein the shape is the second film pattern forming the electronic device, and one of the first transfer patterns defined by the marking pattern is Divided by additional processing to remove those. The method of manufacturing the reticle of claim 13 or 15, wherein the reticle substrate is formed on the transparent substrate by sequentially laminating the semi-transparent film and the etched film having different etching characteristics The shade film is made up. A photomask for manufacturing a first thin film pattern in which a first thin film is patterned on a same substrate, and a second thin film pattern in which a second thin film is patterned The electronic device of the laminated structure includes a first transfer pattern for forming the semi-transparent film and the light-shielding film formed on the transparent substrate in order to form the first thin film pattern, The transfer pattern has a shape for forming the first thin film pattern of the electronic device by exposure, and includes a mark of a line width which is not resolved by the exposure device used in the exposure. The pattern is a second transfer pattern for forming the second thin film pattern of the electronic device, and one of the first transfer patterns defined by the mark pattern can be removed by additional processing. The photomask according to claim 17, wherein the second transfer pattern includes a light transmitting portion surrounded by the semi-transmissive portion, a light transmitting portion surrounded by the light shielding portion, and a semi-transmissive portion surrounded by the light shielding portion, and is semipermeable. Any one of a light shielding portion surrounded by the light portion, a light shielding portion surrounded by the light transmitting portion, and a semi-light transmitting portion surrounded by the light transmitting portion. The photomask according to claim 17 or 18, wherein the mark pattern includes a semi-transmissive portion or a light-transmitting portion having a width of 0.3 to 1.5 μm surrounding a portion of the light-shielding portion of the first transfer pattern. A method of manufacturing a display device, characterized in that it is a method of manufacturing an electronic device as claimed in claim 1 or 2.