JP2013045864A - Method of manufacturing semiconductor device and edge exposure device - Google Patents

Abstract

An object of one embodiment is to provide a semiconductor device manufacturing method and a peripheral exposure apparatus that can reduce dust, for example.
According to one embodiment, a method for manufacturing a semiconductor device is provided. In the method for manufacturing a semiconductor device, a photosensitive agent 3 is applied on a workpiece in the substrate 1. In the semiconductor device manufacturing method, the peripheral exposure of the substrate 1 is performed by irradiating the peripheral portion 1a of the substrate 1 with light from the light source LS via the peripheral exposure mask MK1. The peripheral exposure mask MK1 has a pattern in which the light shielding rate gradually decreases as it approaches the edge 1e of the substrate 1. In the method for manufacturing a semiconductor device, the peripherally exposed portion of the photosensitive agent 3 is removed.
[Selection] Figure 2

Description

  Embodiments described herein relate generally to a semiconductor device manufacturing method and a peripheral exposure apparatus.

  When manufacturing a semiconductor device, a resist is applied onto a film to be processed on a substrate by a coating process, a latent image is formed on the resist by an exposure process, and the resist is developed by a development process, and a resist corresponding to the latent image is formed. A pattern is formed, and the film to be processed is patterned by the etching process using the resist pattern as a mask. At this time, if the resist formed on the periphery of the substrate is left unattended, the resist may peel off. When resist peeling occurs, dust tends to increase. Therefore, conventionally, after a resist is applied to the substrate, the resist in the peripheral portion of the substrate is removed by edge cut processing by thinner or edge cut processing by peripheral exposure processing.

JP 2009-158940 A

  An object of one embodiment is to provide a semiconductor device manufacturing method and a peripheral exposure apparatus that can reduce dust, for example.

  According to one embodiment, a method for manufacturing a semiconductor device is provided. In a method for manufacturing a semiconductor device, a photosensitive agent is applied on a workpiece on a substrate. In the semiconductor device manufacturing method, the peripheral exposure of the substrate is performed by irradiating the peripheral portion of the substrate with light from the light source through the peripheral exposure mask. The peripheral exposure mask has a pattern in which the light shielding rate gradually decreases as it approaches the edge of the substrate. In the method of manufacturing a semiconductor device, the peripherally exposed portion of the photosensitive agent is removed.

FIG. 5 is a view showing the method for manufacturing the semiconductor device according to the first embodiment. FIG. 5 is a view showing the method for manufacturing the semiconductor device according to the first embodiment. FIG. 5 is a view showing the method for manufacturing the semiconductor device according to the first embodiment. FIG. 5 is a view showing the method for manufacturing the semiconductor device according to the first embodiment. FIG. 5 is a view showing the method for manufacturing the semiconductor device according to the first embodiment. FIG. 5 is a view showing the method for manufacturing the semiconductor device according to the first embodiment. FIG. 5 is a view showing the method for manufacturing the semiconductor device according to the first embodiment. 1 is a diagram showing a configuration of a peripheral exposure apparatus according to a first embodiment. FIG. 6 is a view showing a method for manufacturing a semiconductor device according to a second embodiment. FIG. 6 is a view showing a method for manufacturing a semiconductor device according to a second embodiment. FIG. 6 is a view showing a method for manufacturing a semiconductor device according to a second embodiment. FIG. 6 is a view showing a method for manufacturing a semiconductor device according to a second embodiment. The figure which shows the manufacturing method of the semiconductor device concerning a comparative example. The figure which shows the manufacturing method of the semiconductor device concerning a comparative example. The figure which shows the manufacturing method of the semiconductor device concerning another comparative example. The figure which shows the manufacturing method of the semiconductor device concerning another comparative example. The figure which shows the structure of the periphery exposure apparatus concerning another comparative example.

  Exemplary embodiments of a method for manufacturing a semiconductor device will be described below in detail with reference to the accompanying drawings. Note that the present invention is not limited to these embodiments.

  In addition, in this specification, the second film is formed “on” the first film in addition to the case where the second film is formed directly on the first film. The case where the second film is formed on the first film through the third film is also included.

(First embodiment)
A method for manufacturing a semiconductor device according to the first embodiment will be described with reference to FIGS. 1A to FIG. 7C, except for FIG. 2B and FIG. 6B, are process cross-sectional views illustrating a method for manufacturing a semiconductor device, respectively. FIG. 2B and FIG. 6B are diagrams showing the configuration of the peripheral exposure mask.

  In the step shown in FIG. 1A, a substrate 1 is prepared. Then, for example, a film 2 to be processed is formed on the substrate 1 as a material to be processed on the substrate 1. The substrate 1 is a semiconductor substrate, for example, and is formed of, for example, a material whose main component is silicon.

  The processed film 2 is applied to the surface of the substrate 1 (for example, spin-coated) so that a solution containing a material to be processed (for example, a material containing metal as a main component) has a film thickness of 100 nm. ), A film of the applied solution is formed by baking and hardening in a baking process. In the baking process, for example, a two-step baking process is performed in which heating is performed in two stages of 200 ° C. for 60 seconds and 300 ° C. for 60 seconds. The processed film 2 may be formed by a CVD method, a PVD method, or the like. Further, the substrate 1 itself may be used as a workpiece.

  In the step shown in FIG. 1B, a photosensitive agent 3 is applied on the film 2 to be processed. The photosensitive agent 3 can be exposed to light that has passed through the peripheral exposure mask, and is, for example, a positive resist for DUV light (ArF light). For example, the coating film of the photosensitive agent 3 is applied (for example, spin coated) on the surface of the film to be processed 2 so that the solution containing the photosensitive agent 3 has a film thickness of 100 nm, and the film of the applied solution is baked. It is formed by baking. In the baking process, for example, heating is performed at 100 ° C. for 60 seconds.

  In the step shown in FIG. 2A, peripheral exposure of the substrate 1 is performed using the peripheral exposure mask MK1. That is, the peripheral portion 1a of the substrate 1 is irradiated with light from the light source LS via the peripheral exposure mask MK1.

  For example, in the peripheral exposure apparatus 100 shown in FIG. 8, light that has been irradiated from the light source LS and passed through the peripheral exposure mask MK <b> 1 by relatively moving the light source LS and the peripheral exposure mask MK <b> 1 and the substrate 1. The peripheral portion 1a is scanned and exposed. For example, when the substrate 1 is substantially circular in plan view, the light passing through the peripheral exposure mask MK1 is irradiated to the peripheral portion 1a of the substrate 1 with the light source LS and the peripheral exposure mask MK1 fixed. The substrate 1 is rotated while maintaining.

  Specifically, the peripheral exposure apparatus 100 includes a light source LS, an irradiation unit 110, a moving unit 120, a standby unit 130, and peripheral exposure masks MK1 and MK2.

  The light source LS is a light source that generates light that can be exposed to the photosensitive agent 3 via the peripheral exposure masks MK1 and MK2. For example, an ArF light source that generates DUV light (ArF light) is used. Light from the light source LS is applied to the peripheral exposure masks MK1 and MK2.

  One of the peripheral exposure mask MK1 and the peripheral exposure mask MK2 is disposed on the optical axis, and the other is retracted from the optical axis. FIG. 8 shows a state in which the peripheral exposure mask MK1 is disposed on the optical axis and the peripheral exposure mask MK2 is retracted from the optical axis. One of the peripheral exposure mask MK1 and the peripheral exposure mask MK2 arranged on the optical axis is irradiated with light from the light source LS.

  The irradiation unit 110 includes a lens 111 and an irradiation nozzle 112. The lens 111 is disposed between the peripheral exposure masks MK1 and MK2 and the irradiation nozzle 112, and guides light that has passed through the peripheral exposure masks MK1 and MK2 to the irradiation nozzle 112. The irradiation nozzle 112 further guides the light guided from the lens 111 to the moving unit 120 side (substrate 1 side).

  As described above, the moving unit 120 uses the light source LS and the peripheral exposure so that the light passing through the peripheral exposure masks MK1 and MK2 is scanned and exposed to the peripheral portion 1a of the substrate 1 (see FIG. 2A). The masks MK1, MK2 and the substrate 1 are relatively moved. The moving unit 120 includes a stage 121, a suction mechanism 122, a rotation mechanism 123, and an optical sensor (for example, a UV sensor) 124. The substrate 1 is placed on the stage 121, and the substrate 1 is fixed on the stage 121 by the suction mechanism 122. At that time, the optical sensor 124 is used for positioning so that the peripheral portion 1a of the substrate 1 is located immediately below the irradiation nozzle 112. The optical sensor 124 is, for example, a light amount sensor, and is determined by a controller (not shown) that the substrate 1 is placed at a target position on the stage 121 when the amount of received light matches a predetermined target value. The rotation mechanism 123 rotates the stage 121 while the substrate 1 is fixed on the stage 121. As a result, for example, the substrate 1 is rotated while maintaining the light source LS and the peripheral exposure mask MK1 fixed so that the light passing through the peripheral exposure mask MK1 is applied to the peripheral portion 1a of the substrate 1.

  The standby unit 130 includes a carry-in buffer arm 131-1, a carry-in buffer stage 132-1, a carry-out buffer arm 131-2, and a carry-out buffer stage 132-2. The carry-in buffer arm 131-1 carries the substrate 1 to be processed next to the carry-in buffer stage 132-1, and makes it stand by. When the peripheral exposure of the substrate 1 on the stage 121 is completed, the unloading buffer arm 131-2 transports the processed substrate 1 to the unloading buffer stage 132-2, and the loading buffer arm 131-1 next The substrate 1 to be processed is transferred to the stage 121.

  Further, as shown in FIG. 2B, the peripheral exposure mask MK1 has a gradient pattern in which the light shielding rate gradually decreases as it approaches the edge 1e of the substrate 1. Specifically, the peripheral exposure mask MK1 has a gradient pattern in which the aperture ratio gradually increases as the edge 1e of the substrate 1 is approached.

  More specifically, in the peripheral exposure mask MK1, the light transmitting patterns TP1 to TP7 and the light shielding patterns SP2 to SP8 are alternately and repeatedly arranged between the light shielding pattern SP1 and the light transmitting pattern TP8. For example, the pitches P2 to P8 of the arrangement of the light shielding patterns SP2 to SP8 are gradually increased as the edge 1e of the substrate 1 is approached within a resolution limit (for example, 30 nm or less) of the peripheral exposure apparatus 100 (see FIG. 8). It is getting bigger. For example, the width W of the light shielding patterns SP <b> 2 to SP <b> 8 has a substantially constant value within a range below the resolution limit of the peripheral exposure apparatus 100.

  By performing peripheral exposure using the peripheral exposure mask MK1, the film thickness gradually decreases as the edge 1e of the substrate 1 is approached, as indicated by the broken lines in FIGS. 2 (a) and 2 (b). A latent image pattern 3 i of a peripheral exposure pattern having a substantially constant taper angle can be formed in the coating film of the photosensitive agent 3.

  3A, the substrate 1 on which the latent image pattern 3i is formed in the coating film of the photosensitive agent 3 is transported from the peripheral exposure apparatus 100 to an exposure apparatus for forming a predetermined pattern. . The latent image pattern 3 i of the peripheral exposure pattern formed by the peripheral exposure apparatus 100 is developed, and the coating film of the photosensitive agent 3 is patterned so as to have a substantially constant taper angle in the vicinity of the peripheral portion 1 a on the substrate 1. Then, the substrate 1 may be transported to an exposure apparatus for forming a predetermined pattern.

  In the step shown in FIG. 3B, pattern exposure for forming a predetermined pattern on the substrate 1 is performed using the pattern forming mask MK100. That is, the light from the light source LS100 is irradiated to the inner portion 1b of the substrate 1 through the pattern forming mask MK100. The inner part 1b is a part inside the peripheral part 1a (refer FIG. 2A) in the board | substrate 1. FIG. This exposure process is performed, for example, in an ArF exposure apparatus (not shown) under the conditions of NA = 1.35 and dipole illumination. The light source LS100 is a light source that generates light that can form a latent image on the photosensitive agent 3 via the pattern formation mask MK100, and uses, for example, an ArF light source that generates DUV light (ArF light). As the pattern forming mask MK100, for example, a halftone mask having a transmittance of 6% is used. As a result, as shown by a broken line in FIG. 3B, a latent image pattern to be a predetermined pattern is formed in the coating film of the photosensitive agent 3. Further, a baking process is performed. In the baking process, for example, heating is performed at 110 ° C. for 90 seconds.

  In the step shown in FIG. 3C, the latent image pattern including the latent image pattern 3i formed in the coating film of the photosensitive agent 3 is developed. In this development processing, for example, paddle development is performed for a predetermined time (for example, 30 seconds) using a predetermined developer (for example, 2.38 wt% tetramethylammonium hydroxide (TMAH) aqueous solution). Thereby, the coating film of the photosensitive agent 3 is patterned into the predetermined patterns 4-1 to 4-12, and the line and space pattern LSP1 including the predetermined patterns 4-1 to 4-12 is formed. At this time, in the vicinity of the peripheral portion 1a of the substrate 1, the pattern 4-having inclined side surfaces 4-11i1 and 4-12i1 having substantially constant taper angles such that the film thickness gradually decreases as the edge 1e of the substrate 1 is approached. 11, 4-12 are formed.

  In the steps shown in FIGS. 4A and 4B, sidewall patterns 6-1 to 6-8 are formed on the side surfaces of the predetermined patterns 4-1 to 4-12.

  Specifically, in the step shown in FIG. 4A, the film 5 covering the film 2 to be processed and the predetermined patterns 4-1 to 4-12 is formed by, for example, the CVD method. The film 5 is made of a material having a high etching selectivity with respect to the predetermined patterns 4-1 to 4-12 (photosensitive agent 3), and is made of, for example, a material mainly composed of silicon oxide. Note that, before forming the film 5, a slimming process may be performed on the predetermined patterns 4-1 to 4-12 to appropriately adjust the dimensions of the predetermined patterns 4-1 to 4-12.

  In the step shown in FIG. 4B, the film 5 is etched under a highly anisotropic condition by, for example, a dry etching method. Thereby, the part which covers the surface of the to-be-processed film | membrane 2 in the film | membrane 5, the part which covers the upper surface of the predetermined patterns 4-1 to 4-12, and the inclined side surfaces 4-11i1 and 4-12i1 of the patterns 4-11 and 4-12 The portion covering the pattern is selectively removed to form sidewall patterns 6-1 to 6-8.

  In the step shown in FIG. 4C, the predetermined patterns 4-1 to 4-12 are removed. This removal process is performed using, for example, a predetermined etchant (for example, sulfuric acid) by, for example, a wet etching method. Thereby, the side wall patterns 6-1 to 6-8 are selectively left on the film 2 to be processed. That is, the line and space pattern LSP2 including the side wall patterns 6-1 to 6-8 is formed.

  In the step shown in FIG. 5A, the film to be processed 2 is processed. That is, the region 2a (see FIG. 4C) exposed by the sidewall patterns 6-1 to 6-8 in the film to be processed 2 is selectively removed. For example, the sidewall pattern 6-1 to 6-8 is used as a hard mask by a dry etching method or the like, and etching is performed on the film 2 to be processed under a highly anisotropic condition. Thereby, the line patterns 7-1 to 7-8 in the film to be processed 2 are selectively left. That is, the line and space pattern LSP2 is transferred to the film to be processed 2, and the line and space pattern LSP3 including the line patterns 7-1 to 7-8 is formed.

  In the step shown in FIG. 5B, the interlayer insulating film 8 covering the substrate 1 and the line patterns 7-1 to 7-8 is formed by a CVD method or the like. The interlayer insulating film 8 is formed of, for example, a material mainly composed of silicon oxide. Then, a film to be processed 9 is formed on the interlayer insulating film 8 by a process similar to the process shown in FIG. The film 9 to be processed is made of, for example, a material whose main component is metal. Further, a coating film of the photosensitive agent 10 is formed on the film 9 to be processed by the same process as the process shown in FIG. The photosensitive agent 10 is, for example, a photosensitive agent different from the photosensitive agent 3 (see FIG. 1B). For example, the photosensitizer 10 is a photosensitizer having a relatively high etching selectivity of a material to be the sidewall pattern (for example, silicon oxide) with respect to the photosensitizer 10, and etches the material to be the sidewall pattern to the photosensitizer 10. The photosensitizer is smaller in etching selectivity than the photosensitizer 3 (see FIGS. 3A to 3C) of the material to be the sidewall pattern.

  In the step shown in FIG. 6A, the peripheral exposure of the substrate 1 is performed using the peripheral exposure mask MK2. That is, the peripheral portion 1a of the substrate 1 is irradiated with light from the light source LS via the peripheral exposure mask MK2.

  For example, in the peripheral exposure apparatus 100 (see FIG. 8), a peripheral exposure mask MK2 is used instead of the peripheral exposure mask MK1 (see FIG. 2A) at the irradiation position (on the optical axis) of the light from the light source LS. Deploy. Then, the light source LS and the peripheral exposure mask MK2 and the substrate 1 are relatively moved so that the light irradiated from the light source LS and passed through the peripheral exposure mask MK2 is scanned and exposed to the peripheral portion 1a of the substrate 1. To do. For example, when the substrate 1 is substantially circular in plan view, the light passing through the peripheral exposure mask MK2 is irradiated to the peripheral portion 1a of the substrate 1 with the light source LS and the peripheral exposure mask MK2 fixed. The substrate 1 is rotated while maintaining.

  As shown in FIG. 6B, the peripheral exposure mask MK2 is a gradient pattern in which the light shielding rate gradually decreases as it approaches the edge 1e of the substrate 1, and the peripheral exposure mask MK1 (FIG. 2A). ))). For example, when the etching selection ratio of the material to be the sidewall pattern to the photosensitive agent 10 is smaller than the etching selection ratio of the material to be the sidewall pattern to the photosensitive agent 3, the peripheral exposure mask MK2 approaches the edge 1e of the substrate 1. The gradient pattern has such a ratio that the light shielding rate gradually decreases (the absolute value of the slope in the light shielding rate graph) is smaller than that of the peripheral exposure mask MK1.

  Specifically, the peripheral exposure mask MK2 is a gradient pattern in which the aperture ratio gradually increases as it approaches the edge of the substrate 1, and is different from the peripheral exposure mask MK1 (see FIG. 2A). have. For example, when the etching selection ratio of the material to be the sidewall pattern to the photosensitive agent 10 is smaller than the etching selection ratio of the material to be the sidewall pattern to the photosensitive agent 3, the peripheral exposure mask MK2 approaches the edge 1e of the substrate 1. It has a gradient pattern in which the rate of gradually increasing the aperture ratio is smaller than that of the peripheral exposure mask MK1.

  More specifically, in the peripheral exposure mask MK2, the light transmitting patterns TP21 to TP30 and the light shielding patterns SP22 to SP31 are alternately and repeatedly arranged between the light shielding pattern SP21 and the light transmitting pattern TP31. For example, the pitches P22 to P31 of the arrangement of the light shielding patterns SP22 to SP31 are gradually increased toward the edge 1e of the substrate 1 within a resolution limit (for example, 30 nm or less) of the peripheral exposure apparatus 100 (see FIG. 8). It is getting bigger. For example, the widths W22 to W31 of the light shielding patterns SP22 to SP31 are gradually decreased as the edge 1e of the substrate 1 is approached within the range of the resolution of the peripheral exposure apparatus 100 or less.

  By performing peripheral exposure using such a peripheral exposure mask MK2, the film thickness gradually decreases as the edge 1e of the substrate 1 is approached, as indicated by a broken line in FIGS. 6 (a) and 6 (b). A latent image pattern 10 i of a peripheral exposure pattern having a substantially constant taper angle can be formed in the coating film of the photosensitive agent 10.

  In the peripheral exposure mask MK2, the pitches P22 to P31 of the arrangement of the light shielding patterns SP22 to SP31 are gradually increased toward the edge 1e of the substrate 1, and the widths W22 to W31 of the light shielding patterns SP22 to SP31 are increased. This is combined with gradually decreasing as the edge 1e of the substrate 1 is approached. As a result, it is possible to stably form a change in the light shielding rate more gradual than the peripheral exposure mask MK1.

  In the step shown in FIG. 7A, as in the step shown in FIG. 3A, the substrate 1 on which the latent image pattern 10i is formed in the coating film of the photosensitive agent 10 is transferred from the peripheral exposure apparatus 100 by a predetermined amount. It is conveyed to an exposure apparatus for forming a pattern. After developing the latent image pattern 10i and patterning the coating film of the photosensitive agent 10 so as to have a substantially constant taper angle in the vicinity of the peripheral portion 1a of the substrate 1, the substrate 1 is formed to form a predetermined pattern. The point which may be conveyed to exposure apparatus is the same as that of the process shown to Fig.3 (a).

  Thereafter, as shown in FIGS. 7B and 7C, the same processing as the processing after FIG. 3B is performed. At this time, for example, predetermined patterns 11-1 to 11-12 are performed by a process shown in FIG. 7C, that is, a process of developing a latent image pattern including the latent image pattern 10i formed in the coating film of the photosensitive agent 10. A line and space pattern LSP11 including is formed. At this time, in the vicinity of the peripheral portion 1a of the substrate 1, the pattern 11− having inclined side surfaces 11-11i1 and 11-12i1 having substantially constant taper angles such that the film thickness gradually decreases as the edge 1e of the substrate 1 is approached. 11, 11-12 are formed. The taper angles of the inclined side surfaces 11-11i1 and 11-12i1 in these patterns 11-11 and 11-12 are the taper angles of the inclined side surfaces 4-11i1 and 4-12i1 in the patterns 4-11 and 4-12 (FIG. 3 ( c) See). In the processing after FIG. 7C, the patterns 11-1 to 11-12 are directly transferred to the film 9 to be processed without forming side wall patterns on the side surfaces of the predetermined patterns 11-1 to 11-12. Then, the upper layer pattern may be processed.

  In this manner, the substrate 1 is formed by using a sidewall transfer process in which a predetermined pattern of the photosensitive agent is formed, a sidewall pattern is formed on the side surface of the predetermined pattern of the photosensitive agent, and the sidewall pattern is transferred to a film to be processed therebelow. A pattern is formed on the semiconductor device to manufacture a semiconductor device.

  Here, suppose that the edge cut process is performed with a rinse liquid such as thinner instead of the peripheral exposure process shown in FIG. 2A in order to remove the photosensitive agent in the peripheral part 1a of the substrate 1. In this case, as shown in FIG. 13A, a coating film of a photosensitive agent 803i having a substantially upright side surface 803i1 is formed. When processing similar to the step shown in FIG. 3B is performed and then development processing is performed similarly to the step shown in FIG. 3C, a predetermined pattern 804-1 is formed as shown in FIG. 13B. ~ 804-12 are formed. Then, a film to be a sidewall pattern is formed similarly to the process shown in FIG. 4A, and the same process as the process shown in FIG. 4B, that is, film processing (for example, anisotropic etching process). As shown in FIG. 14A, not only the side wall patterns 806-1 to 806-8 are formed on the side surfaces of the predetermined patterns 804-1 to 804-12 but also the peripheral portion 1a of the substrate 1. Unintended sidewall patterns 806-11 and 806-12 are also formed on the side surfaces on the edge 1e side of the patterns 804-11 and 804-12 in the vicinity. Furthermore, if the same process as the process shown in FIG. 4C is performed, the intention is not limited to the side wall patterns 806-1 to 806-8 on the film 2 to be processed, as shown in FIG. 14B. Side wall patterns 806-11 and 806-12 that are not left are also selectively left. Since the unintended side wall patterns 806-11 and 806-12 exist in the vicinity of the peripheral portion 1a of the substrate 1, they are easily peeled off from the film to be processed 2 and tend to increase dust.

  Alternatively, in order to remove the photosensitive agent in the peripheral portion 1a of the substrate 1, instead of the peripheral exposure process using the peripheral exposure mask shown in FIG. 2A, the peripheral exposure process that does not use the peripheral exposure mask. Think about when to do. That is, the peripheral exposure apparatus 900 shown in FIG. 17 is used to perform peripheral exposure processing in which light from the lamp LS900 is irradiated to the substrate 1 as it is without passing through the peripheral exposure mask. The amount of light from the lamp LS900 is adjusted by the illuminance setting diaphragm 913 of the irradiation unit 910, and is guided to the irradiation nozzle 912 when the shutter 914 is opened. The irradiation nozzle 912 guides the guided light to the substrate 1 side. In this case, since the light from the lamp LS900 is light having a broad wavelength spectrum, there is much leakage light, and as shown in FIGS. 15 (a) and 15 (b), a photosensitive having an inclined side surface including a large number of irregularities. A latent image pattern 903i of the agent 903 is formed. When processing similar to the step shown in FIG. 3B is performed and then development processing is performed as in the step shown in FIG. 3C, a predetermined pattern 904-1 is formed as shown in FIG. 15C. ~ 904-12 are formed. At this time, in the vicinity of the peripheral portion 1a of the substrate 1, patterns 904-11 and 904-12 having inclined side surfaces 904-11i and 904-12i including a large number of irregularities are formed. Then, a film to be a sidewall pattern is formed similarly to the process shown in FIG. 4A, and the same process as the process shown in FIG. 4B, that is, film processing (for example, anisotropic etching process). As shown in FIG. 16A, not only the side wall patterns 906-1 to 906-8 are formed on the side surfaces of the predetermined patterns 904-1 to 904-12, but also the peripheral portion 1a of the substrate 1. Unintended side wall patterns 906-11 to 906-16 are also formed on the side surfaces on the edge 1e side of the patterns 904-11 and 904-12 in the vicinity. Furthermore, if the same process as the process shown in FIG. 4C is performed, the intention is not limited to the side wall patterns 906-1 to 906-8 on the film 2 to be processed, as shown in FIG. Side wall patterns 906-11 to 906-16 that are not used are also selectively left. Since the unintended side wall patterns 906-11 to 906-16 exist in the vicinity of the peripheral portion 1a of the substrate 1, they tend to be easily peeled off from the film to be processed 2 and increase dust.

  In contrast, in the first embodiment, the light from the light source LS is transmitted via the peripheral exposure masks MK1 and MK2 having a pattern in which the light shielding rate gradually decreases as the edge 1e of the substrate 1 is approached. Is irradiated to the peripheral portion 1 a of the substrate 1 to perform peripheral exposure of the substrate 1. Thus, by removing the peripherally exposed portions of the photosensitive agents 3 and 10, in the vicinity of the peripheral portion 1 a of the substrate 1, a substantially constant taper that the film thickness gradually decreases as the edge 1 e of the substrate 1 is approached. Patterns 4-11, 4-12, 11-11, and 11-12 of the photosensitive agents 3 and 10 having the inclined side surfaces 4-11i1, 4-12i1, 11-11i1, and 11-12i1 are formed (FIG. 3). (See (c) and FIG. 7 (c)). Thus, after that, when the same process as that shown in FIG. 4B, that is, when the film is processed (for example, anisotropic etching process), the pattern 4-11 in the film to be the sidewall pattern is obtained. 4-12, 11-11, 11-12, the portions covering the inclined side surfaces 4-11i1, 4-12i1, 11-11i1, 11-12i1 can be stably removed (see, for example, FIG. 4B). As a result, it is possible to suppress the formation of an unintended sidewall pattern in the vicinity of the peripheral portion 1a of the substrate 1, so that dust can be reduced.

  In the first embodiment, the peripheral exposure masks MK1 and MK2 have a pattern in which the aperture ratio gradually increases as the edge 1e of the substrate 1 is approached. Thereby, it is possible to easily realize a pattern in which the light shielding rate gradually decreases as the edge 1e of the substrate 1 is approached.

In the first embodiment, the patterns of the peripheral exposure masks MK1 and MK2 are changed according to the application layer. For example, in the peripheral exposure mask MK2, the rate at which the light shielding rate gradually decreases toward the edge 1e of the substrate 1 (the absolute value of the slope in the graph of the light shielding rate) becomes smaller than the peripheral exposure mask MK1. It has a gradient pattern. Thus, even when the etching selectivity of the material to be the sidewall pattern with respect to the photosensitive agent 10 is smaller than the etching selectivity of the material to be the sidewall pattern with respect to the photosensitive agent 3, the material to be the sidewall pattern with respect to the photosensitive agents 3 and 10. Depending on the size of the etching selectivity, for example, the taper angles of the inclined side surfaces 11-11i1 and 11-12i1 in the patterns 11-11 and 11-12 in the vicinity of the peripheral portion 1a of the substrate 1 are set in the vicinity of the peripheral portion 1a of the substrate 1. These patterns 4-11 and 4-12 can be made gentler than the taper angles of the inclined side surfaces 4-11i1 and 4-12i1. That is, the inclination of the patterns 4-11, 4-12, 11-11, 11-12 in the film to be the side wall pattern even if the etching selectivity ratios of the material to be the side wall pattern with respect to the photosensitive agents 3 and 10 are different from each other. The portions covering the side surfaces 4-11i1, 4-12i1, 11-11i1, and 11-12i1 can be stably removed (see, for example, FIG. 4B).
In the peripheral exposure apparatus 100 shown in FIG. 8, instead of using the peripheral exposure masks MK1 and MK2 having different patterns depending on the application layer on the predetermined substrate 1, it is used depending on the type of semiconductor device to be processed. The peripheral exposure masks MK1 and MK2 may be appropriately selected. In this case, depending on the specifications of the semiconductor device such as the dimensions of the pattern formed on the substrate and the manufacturing conditions to be applied, the periphery of the resist pattern formed near the periphery of the substrate should have a desirable taper angle. The peripheral exposure masks MK1 and MK2 used in the exposure apparatus 100 may be selected.

(Second Embodiment)
A semiconductor device manufacturing method according to the second embodiment will be described with reference to FIGS. FIG. 9A to FIG. 12B are process cross-sectional views illustrating a method for manufacturing a semiconductor device, respectively. Below, it demonstrates centering on a different part from 1st Embodiment.

  The process shown in FIG. 9A is performed after the process shown in FIG. In the step shown in FIG. 9A, a mask film 211 is formed on the film 2 to be processed. For example, the mask film 211 is applied to the surface of the film to be processed 2 such that a solution containing a material to be the mask film 211 (for example, a material containing silicon nitride as a main component) has a film thickness of 100 nm (for example, spin film). The film of the applied solution is formed by baking and hardening in a baking process. In the baking process, for example, a two-step baking process is performed in which heating is performed in two stages of 200 ° C. for 60 seconds and 300 ° C. for 60 seconds. Note that the mask film 211 may be formed by a CVD method or the like.

  Then, a photosensitive agent 203 is applied on the mask film 211 by a process similar to the process shown in FIG.

  In the step shown in FIG. 9B, the peripheral exposure of the substrate 1 is performed using the peripheral exposure mask MK201 in the same manner as the step shown in FIG. The peripheral exposure mask MK201 is similar to the first embodiment in that it has a pattern in which the light shielding rate gradually decreases as it approaches the edge 1e of the substrate 1. Further, as shown by a broken line in FIG. 9B, a peripheral exposure pattern latent image pattern 203i having a substantially constant taper angle such that the film thickness gradually decreases as the edge 1e of the substrate 1 is approached. The point that it can be formed in the coating film is the same as in the first embodiment.

  In the step shown in FIG. 9C, similarly to the step shown in FIG. 3A, the substrate 1 on which the latent image pattern 203i is formed in the coating film of the photosensitive agent 203 is transferred from the peripheral exposure apparatus 100 to a predetermined value. It is conveyed to an exposure apparatus for forming a pattern.

  In the step shown in FIG. 10A, pattern exposure for forming a predetermined pattern on the substrate 1 is performed using the pattern forming mask MK300 in the same manner as the step shown in FIG.

  In the step shown in FIG. 10B, the same development processing as in the step shown in FIG. Thereby, the coating film of the photosensitive agent 203 is processed into the predetermined patterns 204-1 to 204-12, and the line and space pattern LSP200 including the predetermined patterns 204-1 to 204-12 is formed. At this time, in the vicinity of the peripheral portion 1a in the substrate 1, the pattern 204- having the inclined side surfaces 204-11i1 and 204-12i1 having substantially constant taper angles such that the film thickness gradually decreases as the edge 1e of the substrate 1 is approached. 11, 204-12 are formed.

  In the step shown in FIG. 10C, the mask film 211 is processed using predetermined patterns 204-1 to 204-12. For example, the mask film 211 is etched with high anisotropy by a dry etching method or the like using the predetermined patterns 204-1 to 204-12 as a mask. Thereby, predetermined patterns 212-1 to 212-12 in the mask film 211 are selectively left. That is, the line and space pattern LSP200 is transferred to the mask film 211, and the line and space pattern LSP201 including the predetermined patterns 212-1 to 212-12 is formed. At this time, also in the line-and-space pattern LSP201 after transfer, in the vicinity of the peripheral portion 1a in the substrate 1, the inclined side surface 212 having a substantially constant taper angle such that the film thickness gradually decreases as the edge 1e of the substrate 1 is approached. Patterns 212-11, 212-12 having -11i1, 212-12i1 are formed.

  In the step shown in FIG. 11A, a film 205 that covers the film to be processed 2 and the predetermined patterns 212-1 to 212-12 is formed in the same manner as the step shown in FIG. Prior to the formation of the film 205, a slimming process is performed on one or both of the predetermined patterns 204-1 to 204-12 and the predetermined patterns 212-1 to 212-12, so that the predetermined patterns 212-1 to 212-212 are formed. You may adjust the dimension of -12 suitably.

  In the step shown in FIG. 11B, as in the step shown in FIG. 4B, the film 205 is etched under a highly anisotropic condition by, for example, a dry etching method. Thereby, the part which covers the surface of the to-be-processed film | membrane 2 in the film | membrane 205, the part which covers the upper surface of predetermined | prescribed pattern 212-1 to 212-12, and the inclined side surface 212-11i1, 212-12i1 of pattern 212-11,212-12 The side wall patterns 206-1 to 206-8 are formed.

  In the step shown in FIG. 11C, similar to the step shown in FIG. 4C, the predetermined patterns 212-1 to 212-12 are removed and the side wall patterns 206-1 to 206-8 are selectively left. . That is, the line and space pattern LSP202 including the side wall patterns 206-1 to 206-8 is formed.

  In the step shown in FIG. 12A, the processed film 2 is processed in the same manner as in the step shown in FIG. 5A, and the line patterns 207-1 to 207-8 in the processed film 2 are selectively selected. leave. That is, the line and space pattern LSP202 is transferred to the film to be processed 2, and the line and space pattern LSP203 including the line patterns 207-1 to 207-8 is formed.

  In the step shown in FIG. 12B, an interlayer insulating film 208, a film to be processed 209, a mask film 213, and a coating film of a photosensitive agent 210 are sequentially formed so as to cover the substrate 1 and the line patterns 207-1 to 207-8. To do. Thereafter, for example, processing similar to the processing after FIG. 9B is performed to process the upper layer pattern on the processing target film 209.

As described above, in the second embodiment, instead of forming the sidewall pattern on the side surface of the predetermined pattern of the photosensitive agent, the predetermined pattern of the photosensitive agent is transferred as the predetermined pattern of the mask film, and then the mask is formed. A sidewall transfer process is performed by forming a sidewall pattern on the side surface of a predetermined pattern of the film and transferring the sidewall pattern to the underlying film. Even in this case, the light from the light source LS passes through the peripheral exposure mask MK201 or the like (see FIG. 9B) having a pattern in which the light shielding rate gradually decreases as the edge 1e of the substrate 1 is approached. Is irradiated to the peripheral portion 1 a of the substrate 1 to perform peripheral exposure of the substrate 1. Thereafter, the peripherally exposed portion of the photosensitive agent 203 is removed, and pattern transfer using the patterned photosensitive agent 203 as a mask is performed on the mask film 211, so that the substrate 1 is in the vicinity of the peripheral portion 1 a. Patterns 212-11 and 212-12 of the mask film 211 having inclined side surfaces 212-11i and 212-12i having substantially constant taper angles such that the film thickness gradually decreases as approaching the edge 1e (FIG. 10). (See (c)). Thereby, when the process similar to the process shown in FIG. 4B (that is, anisotropic etching process) is performed thereafter, the slopes of the patterns 212-11 and 212-12 in the films to be the sidewall patterns are obtained. The portions covering the side surfaces 212-11i1, 212-12i1 can be stably removed (see FIG. 11B). As a result, it is possible to suppress the formation of an unintended sidewall pattern in the vicinity of the peripheral portion 1a of the substrate 1, so that dust can be reduced.
In the above embodiment, an example of a method for manufacturing a semiconductor device that performs a sidewall transfer process has been described. However, the present invention is not limited to this.
Even if the side wall pattern is not formed on the side surface of the predetermined pattern, the side surface of the predetermined pattern is set as the inclined side surface in the vicinity of the peripheral portion of the substrate, thereby preventing the unintended deposited film from remaining on the side of the predetermined pattern. Therefore, it is possible to prevent the generation of dust due to peeling of the remaining deposited film.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  1 Substrate, 2, 9, 209 Film to be processed, 3, 10, 203, 210 Photosensitive agent, 4-1 to 4-12, 204-1 to 204-12, 212-1 to 212-12 Predetermined pattern, 6 -1 to 6-8, 206-1 to 206-8 Side wall pattern, 7-1 to 7-8, 207-1 to 207-8 Line pattern, 100 Peripheral exposure device, 110 Irradiation unit, 111 Lens, 112 Irradiation nozzle , 120 moving unit, 121 stage, 122 suction mechanism, 123 rotating mechanism, 124 optical sensor, 130 standby unit, 131-1 carrying-in buffer arm, 131-2 carrying-out buffer arm, 132-1, carrying-in buffer stage, 132- 2 Unloading buffer stage, 211, 213 Mask film, LS, LS100 Light source, MK1, MK2, MK201 Peripheral exposure mask Mask, MK100, MK300 Mask for pattern formation.

Claims (5)

Applying a photosensitizer on the workpiece on the substrate;
By irradiating the peripheral part of the substrate with light from a light source through a peripheral exposure mask having a pattern in which the light shielding rate gradually decreases as approaching the edge of the substrate, the periphery of the substrate Performing exposure and performing pattern exposure on the substrate inside the peripheral portion of the substrate by an exposure process using a pattern forming mask; and
Removing the peripherally exposed portion of the photosensitive agent and patterning a portion inside the peripheral portion of the substrate on which the pattern exposure of the photosensitive agent has been performed;
Forming a side wall pattern on a side surface of a predetermined pattern formed in a portion inside the peripheral portion of the substrate based on the pattern exposure;
Processing the workpiece using the sidewall pattern as a mask;
A method for manufacturing a semiconductor device, comprising: Applying a photosensitizer on the workpiece on the substrate;
By irradiating the peripheral part of the substrate with light from a light source through a peripheral exposure mask having a pattern in which the light shielding rate gradually decreases as approaching the edge of the substrate, the periphery of the substrate Performing exposure,
Removing the peripherally exposed portion of the photosensitizer;
A method for manufacturing a semiconductor device, comprising: 3. The method of manufacturing a semiconductor device according to claim 1, wherein the peripheral exposure mask has a pattern in which an aperture ratio gradually increases as approaching an edge of the substrate. Forming a film to be processed on the substrate;
Applying a second photosensitive agent on the film to be processed;
Light from the light source is transmitted through a second peripheral exposure mask having a pattern in which the light shielding rate gradually decreases as it approaches the edge of the substrate and has a different pattern from the peripheral exposure mask. Irradiating the peripheral part of the substrate to perform peripheral exposure of the substrate;
Removing the peripherally exposed portion of the second photosensitive agent;
The method of manufacturing a semiconductor device according to claim 1, further comprising: A light source;
It has a pattern in which the light shielding rate gradually decreases as it approaches the edge of the substrate, and the peripheral exposure mask of the substrate irradiated with light from the light source,
A moving unit that relatively moves the light source, the peripheral exposure mask, and the substrate so that the light that has passed through the peripheral exposure mask is scanned and exposed to the peripheral portion of the substrate;
A peripheral exposure apparatus comprising:

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