JP2005051024A - Substrate processing method and substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate processing method and a substrate processing apparatus capable of shortening development processing time.
The following steps are provided. A formation film including at least the photosensitive resin film provided on the surface is formed on the surface of the substrate to be processed. Next, a developer film is formed on the formed film. Next, the temperature of the formed film is increased by irradiating light from the upper side of the developer that contributes more to the temperature rise of the formed film than the temperature of the developer.
[Selection] Figure 1

Description

  The present invention relates to a substrate processing method and a substrate processing apparatus.

  A resist pattern used in a lithography process in the manufacturing process of a semiconductor device is generally formed as follows. First, a resist film is formed on a semiconductor wafer, then a predetermined pattern is transferred to the resist film by exposure, and then development processing is performed. In this resist pattern forming process, it is necessary to shorten the processing time in each process such as application and development of a resist film from the viewpoint of obtaining a high throughput. In general, the rinsing process performed after the development process is performed in the same apparatus following the development process. The rinsing process required for the development process requires a certain amount of processing time in order to reduce defects caused by the development. Therefore, in the developing process, the time required for processes other than the rinsing process, for example, the development time is shortened. It is possible to make it.

  As one method for shortening the development time, there is known a method of increasing the development speed by increasing the temperature of the developer. As a specific method for raising the temperature of the developing solution, a developing device having a function of irradiating the entire surface of the wafer with light that the resist does not sensitize during development has been proposed (Japanese Patent Laid-Open No. 3-259511). Further, a developing device and a developing method using an infrared heater (Japanese Patent Laid-Open No. 2001-102292) and a halogen lamp (Japanese Patent Laid-Open No. 2002-343711) as heat sources have been proposed.

Prior art document information related to the invention of this application includes the following.
JP-A-3-259511 Japanese Patent Laid-Open No. 2001-102292 JP 2002-343711 A

  In the above publication, the developer is heated from the surface by irradiating light from above the semiconductor wafer with the developer formed on the surface of the resist film. In the case of such a method, since the developer has a property of absorbing irradiation light, the intensity of light decreases as the distance from the surface of the developer, that is, the closer to the surface of the resist film. Therefore, the temperature of the developer near the resist film is unlikely to rise. Further, since the heated portion of the developer rises due to convection, the temperature at the bottom of the developer (near the resist film) is less likely to rise. For this reason, the time required to raise the temperature of the developer becomes long, and as a result, it is difficult to shorten the development time.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a substrate processing method and a substrate processing apparatus capable of shortening the development processing time.

  A substrate processing method according to a first aspect of the present invention includes a step of forming a formation film including at least a photosensitive resin film provided on a surface of a substrate to be processed, and a developer film on the formation film. And a step of raising the temperature of the formed film from above the developer by irradiating light that contributes more to the temperature rise of the formed film than the temperature of the developer. It is characterized by doing.

  A substrate processing apparatus according to a second aspect of the present invention provides a substrate holding means for holding a substrate to be processed on which a formation film including a photosensitive resin film is provided, and a developer is supplied onto the formation film. And a light source that generates light that contributes more to the temperature rise of the formation film than the temperature increase of the developer, and is disposed above the substrate holding means to irradiate the formation film with the light. And a light irradiating means.

  Furthermore, the embodiments of the present invention include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, when an invention is extracted by omitting some constituent elements from all the constituent elements shown in the embodiment, when the extracted invention is carried out, the omitted part is appropriately supplemented by a well-known common technique. It is what is said.

  ADVANTAGE OF THE INVENTION According to this invention, the substrate processing method and substrate processing apparatus which can shorten development processing time can be provided.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, components having substantially the same function and configuration are denoted by the same reference numerals, and redundant description will be given only when necessary.

(First embodiment)
1 and 2 are views schematically showing a substrate processing apparatus according to a first embodiment of the present invention. FIG. 1 shows a state during development, and FIG. 2 shows a state during rinsing. As shown in FIGS. 1 and 2, a stage 3 (substrate holding means) is provided on a rotating shaft 2 in the chamber 1. On the stage 3, for example, a wafer W (substrate to be processed) having a diameter of 300 mm is disposed. Above the stage 3, a developer supply nozzle 4 is provided. A developer is supplied to the developer supply nozzle 4 via a developer supply pipe. Further, the developer supply nozzle 4 (developer supply means) is driven by the developer supply nozzle drive section 5 (developer supply means drive section) to scan the wafer W across both ends of the wafer W. To move.

  Further, at the time of rinsing, for example, a rinsing liquid supply nozzle 6 (rinsing liquid supply means) that discharges a rinsing liquid such as pure water moves to the center of the wafer, and the rinsing liquid is discharged there. The rinse liquid is supplied to the rinse liquid supply nozzle 6 via the rinse liquid supply pipe.

  A plurality of light irradiation units 11 (light irradiation means) are provided in the upper part of the chamber 1. The light emitted from the light source 12 provided outside the chamber 1 is introduced into each light irradiation unit 11 by an optical fiber or the like. On / off of light irradiation of each light irradiation unit 11 is independently controlled by an irradiation control unit (not shown).

  The light source 12 is provided outside the chamber 1 and includes at least the light emitting unit 21 or the light emitting unit 21 and the spectroscopic unit 22. The light source 12 will be described in detail later.

  Next, substrate processing steps using the substrate processing apparatus of FIGS. 1 and 2 will be described. First, prior to the processing by the substrate processing apparatus of FIG. 1, an insulating film, a conductive film, and the like of a number of layers corresponding to the stage where the lithography process is performed are formed on the wafer W. That is, for example, in the stage of a lithography process for forming a gate electrode, a gate insulating film and a material film for the gate electrode are already formed on the wafer W. Therefore, the uppermost film on the wafer W is a material film for the gate electrode. Similarly, in the case of a lithography process for forming contact holes in an interlayer insulating film, for example, the uppermost film on the wafer W is an interlayer insulating film. Accordingly, the material film of the uppermost layer differs depending on which stage of the manufacturing process of the semiconductor device the lithography process is. The uppermost material film is an object to be etched. Hereinafter, as shown in FIG. 3, each layer formed on the wafer W is generically referred to as a base film 31, and a layer on the surface of the base film 31 is an object to be etched.

  As shown in FIG. 4, an antireflection film is formed on the surface of the base film 31 by, for example, a spin coating method. Next, the antireflection film 32 is formed on the base film 31 by baking the wafer W under conditions of, for example, 190 ° C. and 60 seconds.

  Next, for example, a material solution of a positive chemically amplified resist is dropped on the antireflection film 32. Next, a pre-bake process is performed on the wafer W under conditions of 130 ° C. and 60 seconds, for example. The pre-baking process is a heat process for volatilizing the solvent of the resist material solution. As a result of the pre-baking process, a 300 nm resist film 33 (photosensitive resin film) is formed on the antireflection film 32, for example. Hereinafter, the base film 31, the antireflection film 32, and the resist film 33 including at least the resist film 33 are collectively referred to as a formation film 34.

  Next, the wafer W is cooled to room temperature and then transferred to an exposure apparatus using, for example, an ArF excimer laser (wavelength 193 nm) as a light source. In the exposure apparatus, reduced projection exposure is performed on the wafer W using a photomask for exposure. As a result, a latent image having a repetitive pattern with a line dimension = 100 nm and a space dimension = 100 nm is formed on the resist film 33.

  Next, the wafer W is transferred to a heat treatment apparatus. In the heat treatment apparatus, a heat treatment called PEB (Post Exposure Bake) is performed on the wafer W under conditions of, for example, 130 ° C. and 90 seconds. Next, the wafer W is cooled to room temperature.

  Next, the wafer W is transferred to the substrate processing apparatus (developing apparatus) in FIG. The wafer W is chucked so as to be horizontal on the stage 3 in the developing device. The developer supply nozzle 4 moves so as to scan the wafer W while discharging the developer. As a result, as shown in FIG. 5, a film made of the developer 41 is formed on the formation film 34. After the scan is completed, the developer supply nozzle 4 is retracted out of the wafer W.

  Next, the developer 41 is heated by the light irradiated from the light irradiation unit 11. The light introduced from the light source 12 to the light irradiation unit 11 is selected so that the contribution of the resist film 33 to the temperature rise is greater than the contribution of the developer 41 to the temperature rise. For example, light having a wavelength that is hardly absorbed by the developer 41 is most preferable.

  Specifically, the irradiation light can be infrared light. More specifically, the light from which the wavelength absorbed by the developer 41 is removed is used. In consideration of the fact that water, which is the main component of the developer 41, absorbs light having a wavelength of 2.4 μm to 3.3 μm in the infrared region, as shown in FIG. Can be used as the spectroscopic unit 22. For example, a halogen lamp is used as the light emitting unit 21. A filter that removes 1.7 to 1.9 μm, which is another wavelength band that is easily absorbed, can also be used.

  By irradiating the developer 41 with light having such characteristics, the irradiated light reaches the resist film 33 without being absorbed much by the developer 41. As a result, the surface of the resist film 33 is heated, and the temperature of the bottom of the developer 41 (interface with the resist film 33) rises due to the heat generated by the resist film 33. As one example, the operation time of the light irradiation unit 11 was controlled so that the surface temperature of the resist film 33 was 50 ° C. By performing development under the above conditions, the development reaction is accelerated. After the development processing, the light irradiation unit 11 is turned off.

  Next, as shown in FIG. 2, the rinsing liquid 7 is supplied from the rinsing liquid supply nozzle 6 toward the wafer W while rotating the rotating shaft 2, thereby performing a rinsing process (development stop process). After the rinsing process, the wafer W is dried by, for example, spin drying.

  According to the first embodiment of the present invention, light having such characteristics that the contribution to the temperature rise of the resist film 33 is greater than the contribution to the temperature rise of the developer 41 is irradiated to the wafer W during the development process. . For this reason, the temperature of the resist film 33 (typically the surface of the resist film 33) rises faster than the developer 41 by the irradiation light. Due to the resist film 33 whose temperature has risen, the temperature of the interface portion with the resist film 33, that is, the bottom portion of the developer 41 rises. In the conventional method, it is possible to shorten the development processing time by efficiently heating the bottom portion which took a long time to raise the temperature.

  Further, convection occurs throughout the developer 41 with the bottom as a base point. For this reason, the product (dissolved product) generated by the reaction between the resist film 33 and the developer 41 is efficiently diffused without remaining in the generated place. Therefore, it is possible to avoid the development process from fluctuating due to the density of the pattern of the resist film 33. As a result, the dimensional variation depending on the density of the pattern of the resist film 33 can be greatly reduced.

  In the conventional method, the development time required to avoid deviating from a desired specification due to fluctuations in the pattern size of the resist film 33 is 30 seconds. As a result of performing the development process by taking the above-described conditions of this embodiment as an example, the time required to obtain the resist film 33 within the specifications was 15 seconds.

  Note that, as described above, irradiation light that contributes greatly to the temperature rise of the formation film 34 including the resist film 33 is used from the developer 41. That is, the temperature of any one of the films constituting the formation film 34 may be increased first. However, it is most preferable from the viewpoint of efficiency to use irradiation light having the characteristic of increasing the temperature of the resist film 33 facing the developing solution 41 most quickly.

(Second Embodiment)
In the second embodiment, one light irradiation unit is used, and the light irradiation unit and the rinse liquid discharge nozzle move so as to scan the wafer W. Further, the characteristics of light irradiated to the developer are the same as those in the first embodiment.

  FIG. 7 is a diagram schematically showing a configuration of a substrate processing apparatus according to the second embodiment of the present invention. As shown in FIG. 7, only one light irradiation unit 11 is provided and is driven by the light irradiation unit driving unit 51. The light irradiation unit 11 moves so as to scan across the both ends of the wafer W on the wafer W by the light irradiation unit driving unit 51 (light irradiation means driving unit). From the light irradiation part 11, the light of the characteristic similar to 1st Embodiment is irradiated. Further, the rinsing liquid supply nozzle 6 moves so as to scan across both ends of the wafer W by the rinsing liquid supply nozzle driving unit 52 (rinsing liquid supply unit driving unit).

  Next, development processing using the substrate processing apparatus having the above configuration will be described. During a series of operations from supplying the developing solution, increasing the temperature of the developing solution, and stopping development, the developing solution supply nozzle 4, the light irradiation unit 11, and the rinsing solution supply nozzle 6 are driven to draw a similar locus.

  According to the second embodiment of the present invention, the light for increasing the temperature of the developer 41 has the same characteristics as the first embodiment. For this reason, the effect similar to 1st Embodiment can be acquired. Therefore, the uniformity of the dimension of the resist pattern in the wafer surface can be improved.

(Third embodiment)
In the third embodiment, in addition to the features of the second embodiment, the rinse liquid supply nozzle is configured to generate a turbulent flow in the developer.

  FIG. 8 is a diagram schematically showing a configuration of a substrate processing apparatus according to the third embodiment of the present invention. As shown in FIG. 8, the rinse liquid supply nozzle 6 is arranged to be inclined with respect to the wafer W. FIG. 9 is a diagram showing a state at the time of development processing using the substrate processing apparatus shown in FIG. As shown in FIG. 9, a turbulent flow 61 is generated in the developer 41 by the rinse liquid 7 supplied from the rinse liquid supply nozzle 6.

  According to the third embodiment of the present invention, the same effect as in the first and second embodiments can be obtained. Furthermore, according to the third embodiment, the rinsing liquid supply nozzle 6 is arranged to be inclined with respect to the wafer W. For this reason, when the rinse liquid 7 is discharged toward the developer 41, a turbulent flow 61 is generated in the developer 41. Therefore, the replacement of the developing solution 41 with the rinsing solution 7 can be promoted, and the warmed developing solution 41 can be efficiently cooled. Therefore, the development processing time can be shortened.

  In addition, in the category of the idea of the present invention, those skilled in the art can conceive of various changes and modifications, and it is understood that these changes and modifications also belong to the scope of the present invention. .

1 is a diagram schematically showing a configuration of a substrate processing apparatus according to a first embodiment of the present invention. 1 is a diagram schematically showing a configuration of a substrate processing apparatus according to a first embodiment of the present invention. The figure which shows schematically a part of process process of the wafer W. FIG. The figure which shows the process following FIG. 3 schematically. The figure which shows the process following FIG. 4 schematically. The figure which shows the degree absorbed by water according to the wavelength of light. The figure which shows schematically the structure of the substrate processing apparatus which concerns on 2nd Embodiment of this invention. The figure which shows schematically the structure of the substrate processing apparatus which concerns on 3rd Embodiment of this invention. The figure which shows the state at the time of the developing process using the substrate processing apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Chamber, 2 ... Rotating shaft, 3 ... Stage, 4 ... Developer supply nozzle, 5 ... Developer supply nozzle drive part, 6 ... Rinse solution supply nozzle, 7 ... Rinse solution, W ... Wafer, 11 ... Light irradiation part , 12 ... light source, 21 ... light emitting part, 22 ... spectroscopic part, 31 ... base film, 32 ... antireflection film, 33 ... resist film, 34 ... formation film, 41 ... developer, 51 ... light irradiation part drive part, 52 ... rinse liquid supply nozzle drive unit, 61 ... turbulent flow.

Claims (18)

Forming a formation film including a photosensitive resin film provided at least on the surface of the substrate to be processed;
Forming a developer film on the forming film;
Irradiating light from above the developing solution that contributes more to the temperature rise of the forming film than the temperature rising of the developing solution to raise the temperature of the forming film;
The substrate processing method characterized by comprising.   The substrate processing method according to claim 1, wherein the light is infrared light.   The substrate processing method according to claim 1, wherein the light does not include a wavelength of 2.4 to 3.3 μm.   The substrate processing method according to claim 1, wherein the light does not include a wavelength of 1.7 to 1.9 μm.   The substrate processing method according to claim 1, wherein the light has a wavelength that is not substantially absorbed by the developer.   The substrate processing method according to claim 1, further comprising a step of stopping development by supplying a rinsing solution toward the developer after the step of increasing the temperature of the formed film. The step of forming the developer film includes a step of supplying the developer while a developer supply unit scans above the formation film,
The step of increasing the temperature of the formation film includes a step of irradiating the light along the locus of the developer supply means with the light irradiation means above the formation film,
The step of stopping the development includes a step in which a rinsing liquid supply unit supplies the rinsing liquid along a locus of the light irradiation unit above the formation film.
The substrate processing method according to claim 6.   The substrate processing method according to claim 6, wherein the step of stopping the development includes a step of supplying the rinse solution with an inclination to the developer.   The substrate processing method according to claim 6, wherein the step of stopping the development includes a step of supplying pure water having a temperature lower than that of the developer toward the developer. Substrate holding means for holding a substrate to be processed on which a formation film including a photosensitive resin film provided on a surface is formed;
Developer supply means for supplying a developer onto the formation film;
A light source that generates light that greatly contributes to the temperature rise of the forming film than the temperature rise of the developer;
A light irradiation means installed above the substrate holding means and irradiating the formation film with the light;
A substrate processing apparatus comprising:   The substrate processing apparatus according to claim 10, wherein the light source includes a light emitting unit that generates infrared light. The light source is
A light emitting unit;
A filter that removes a wavelength of 2.4 to 3.3 μm of light emitted from the light emitting unit;
The substrate processing apparatus according to claim 10, further comprising: The light source is
A light emitting unit;
A filter that removes a wavelength of 1.7 to 1.9 μm of light emitted from the light emitting unit;
The substrate processing apparatus according to claim 10, further comprising:   The substrate processing apparatus according to claim 10, wherein the light source includes a light emitting unit that generates light having a wavelength that is not substantially absorbed by the developer.   The substrate processing apparatus according to claim 10, further comprising a rinsing liquid supply unit that supplies a rinsing liquid toward the developer. A developer supply means driving section for driving the developer supply means so that the developer supply means supplies the developer while scanning above the formation film;
A light irradiating means driving unit for driving the light irradiating means so that the light irradiating means irradiates the light along the locus of the developer supply means above the formation film;
A rinsing liquid supply means driving section for driving the rinsing liquid supply means so that the rinsing liquid supply means supplies the rinsing liquid along the locus of the light irradiation means above the formation film;
The substrate processing apparatus according to claim 15, further comprising:   The substrate processing apparatus according to claim 15, wherein the rinsing liquid supply unit is arranged so that the rinsing liquid is supplied with an inclination to the developer.   The substrate processing apparatus according to claim 15, wherein the rinsing liquid supply means includes means for supplying pure water having a temperature lower than that of the developer toward the developer.

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