Imprint method and semiconductor device manufacturing method

Abstract

To provide an imprint method and a semiconductor device manufacturing method capable of reducing defects.SOLUTION: An imprint method according to an embodiment includes applying a first photocurable resin to a central region of a substrate to form a liquid film of the first photocurable resin, placing droplets of a second photocurable resin in a peripheral region of the substrate, pressing a template against the first and second photocurable resins, irradiating light to cure the first and second photocurable resins, and releasing the template from the first and second photocurable resins to form a pattern on the substrate.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] An embodiment of the present invention relates to an imprint method and a method for manufacturing a semiconductor device. [Background technology]

[0002] Imprint processing is sometimes used in the manufacturing process of semiconductor devices. In imprint processing, a template with projections and recesses is pressed against a resist layer formed in a predetermined region of a substrate for each shot. The recesses of the template are filled with resist, forming projections in the resist layer.

[0003] For example, if the amount of resist layer formed in a given area is small, the resist may not be fully filled in the recesses of the template. Also, the substrate and the template may come into contact with each other, causing shear forces that may impede the alignment operation. As a result, defects may occur.

[0004] On the other hand, for example, if the resist layer is formed protruding from a predetermined region, the template may be contaminated by the resist layer when the template is pressed against it, which may cause defects in the next shot to be processed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2022-49853 [Patent Document 2] JP 2022-144930 A [Patent Document 3] Patent Publication No. 2021-44299 [Patent Document 4] JP 2019-135760 A [Patent Document 5] JP 2017-162929 A [Patent Document 6] JP 2017-118062 A Summary of the Invention [Problem to be solved by the invention]

[0006] An object of one embodiment is to provide an imprint method and a method for manufacturing a semiconductor device that can reduce defects. [Means for solving the problem]

[0007] An imprinting method of one embodiment includes applying a first photocurable resin to a central region of a substrate to form a liquid film of the first photocurable resin, placing droplets of a second photocurable resin in a peripheral region of the substrate, pressing a template against the first and second photocurable resins, irradiating light to cure the first and second photocurable resins, and releasing the template from the first and second photocurable resins to form a pattern on the substrate. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of the arrangement of an imprint apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of a wafer obtained in the process of manufacturing the semiconductor device according to the first embodiment. [Diagram 3] 1A to 1C are diagrams showing a process of forming a wafer in the process of manufacturing the semiconductor device according to the first embodiment. [Figure 4] 3A to 3C are views showing a process of forming a liquid film of a first resist material on a wafer in the process of manufacturing the semiconductor device according to the first embodiment. [Diagram 5] 3A to 3C are views showing an imprint process performed on a wafer in the process of manufacturing the semiconductor device according to the first embodiment. [Figure 6] 3A to 3C are views showing an imprint process performed on a wafer in the process of manufacturing the semiconductor device according to the first embodiment. [Figure 7] 3A to 3C are diagrams showing a process for processing a film to be processed in the process of manufacturing the semiconductor device according to the first embodiment. [Figure 8]6A to 6C are views showing processes performed on a wafer in the process of manufacturing a semiconductor device according to a modified example of the first embodiment. [Figure 9] FIG. 13 is a diagram showing an example of the arrangement of an imprint apparatus according to a second embodiment. [Figure 10] FIG. 11 is a schematic diagram showing an example of a coverage map according to the second embodiment. [Figure 11] 10A to 10C are views showing processes performed on a wafer in the process of manufacturing a semiconductor device according to a second embodiment. [Figure 12] 10A to 10C are views showing processes performed on a wafer in the process of manufacturing a semiconductor device according to a modified example of the second embodiment. [Figure 13] 1A to 1C are diagrams illustrating a part of a process for manufacturing a semiconductor device according to a comparative example. [Figure 14] 1A to 1C are diagrams illustrating a part of a process for manufacturing a semiconductor device according to a comparative example. [Figure 15] 1A to 1C are diagrams illustrating a part of a process for manufacturing a semiconductor device according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that the present invention is not limited to the following embodiments. In addition, the components in the following embodiments include those that a person skilled in the art can easily imagine or are substantially the same.

[0010] [Embodiment 1] Hereinafter, the first embodiment will be described in detail with reference to FIGS.

[0011] Fig. 1 is a diagram showing an example of the configuration of an imprint apparatus 1 according to embodiment 1. As shown in Fig. 1, the imprint apparatus 1 includes a template stage 81, a wafer stage 82, a reference mark 85, an alignment sensor 86, a liquid dropping device 87, a stage base 88, a light source 89, a control unit 90, and a storage unit 91.

[0012] A template 10 for transferring a pattern onto a wafer 30 serving as a substrate is installed in the imprint apparatus 1. The template 10 is made of a transparent material such as quartz.

[0013] 1 illustrates a wafer 30 before the imprint process. A first resist material 160 is formed in a central region on the wafer 30. The imprint apparatus 1 is configured as an apparatus that performs an imprint process in which a second resist material 170 is dropped onto an outer circumferential region on the wafer 30 and a pattern of a template 10 is transferred to the first resist material 160 and the second resist material 170.

[0014] Moreover, an inspection apparatus 11 is connected to the control unit 90 of the imprint apparatus 1. The inspection apparatus 11 is an apparatus that performs a predetermined inspection on the wafer 30 before the imprint process, i.e., after the first resist material 160 has been formed. The inspection apparatus 11 is, for example, an optical microscope. The inspection apparatus 11 transmits measurement data as the inspection result to the control unit 90. Moreover, the inspection apparatus 11 stores the measurement data in a memory unit 91.

[0015] The wafer stage 82 includes a wafer chuck 84 and a main body 83. The wafer chuck 84 fixes the wafer 30 at a predetermined position on the main body 83. A reference mark 85 is provided on the wafer stage 82. The reference mark 85 is used for alignment when the wafer 30 is loaded onto the wafer stage 82.

[0016] The wafer stage 82 places the wafer 30 thereon and moves within a plane (horizontal plane) parallel to the placed wafer 30. The wafer stage 82 moves the wafer 30 below a liquid dropping device 87 (described later) when dropping the second resist material 170 onto the outer circumferential region of the wafer 30, and moves the wafer 30 below the template 10 when transferring a pattern to the first resist material 160 and the second resist material 170 on the wafer 30.

[0017] The stage base 88 supports the template 10 by the template stage 81 and moves in the up-down direction (vertical direction).

[0018] An alignment sensor 86 is provided on the stage base 88. The alignment sensor 86 detects the position of the wafer 30 and the position of the template 10 based on alignment marks provided on the wafer 30 and the template 10.

[0019] The liquid dropping device 87 drops droplets of the second resist material 170 on the wafer 30 by an inkjet method. The inkjet head of the liquid dropping device 87 has a plurality of fine holes. The liquid dropping device 87 drops droplets of the second resist material 170 from the plurality of fine holes to a predetermined position on the wafer 30. At this time, the liquid dropping device 87 arranges the droplets of the second resist material 170 with a positional accuracy of ±20 to 30 um. In this way, the liquid dropping device 87 can form droplets of the second resist material 170 on the wafer 30 with relatively high accuracy. The second resist material 170 is a chemical liquid such as a resist that is hardened when irradiated with light. The second resist material 170 is an example of a second photocurable resin.

[0020] The light source 89 is, for example, a device that irradiates ultraviolet light, and is provided above the stage base 88. The light source 89 irradiates light from above the template 10 in a state in which the template 10 is pressed against the first resist material 160 and the second resist material 170. This causes the first resist material 160 and the second resist material 170 to harden.

[0021] The control unit 90 controls each unit of the imprint apparatus 1. The control unit 90 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), and is configured to include a computer that performs predetermined control processing according to a program.

[0022] Specifically, the control unit 90 controls the template stage 81, the wafer stage 82, the liquid dropping device 87, the stage base 88, the light source 89, etc. At this time, the control unit 90 also refers to the measurement data acquired from the above-mentioned inspection device 11 when controlling each part.

[0023] The storage unit 91 stores the measurement data acquired by the inspection device 11. The storage unit 91 also stores the measurement data and information related to the coating device that processed the wafer 30, etc., in association with each other.

[0024] (Method of manufacturing a semiconductor device) 2 to 7, an example of a method for manufacturing a semiconductor device including an imprint process using the imprint apparatus 1 of embodiment 1 will be described. The method for manufacturing a semiconductor device of embodiment 1 includes an imprint process on a wafer 30.

[0025] First, a process for forming a wafer 30 to be subjected to the imprint process will be described.

[0026] Fig. 2 is a diagram showing an example of a wafer 20 obtained in the process of manufacturing the semiconductor device according to embodiment 1. Fig. 2(a) is a plan view of the wafer 20, and Fig. 2(b) is a cross-sectional view of the wafer 20. The wafer 20 becomes a wafer 30 through the process shown in Fig. 3 described below.

[0027] As shown in FIGS. 2( a ) and 2 ( b ), a wafer 20 has an element formation region 21 and a bevel region 22 .

[0028] The bevel region 22 is a ring-shaped region that forms a step in the outer edge region (periphery) of the wafer 20. The width of the bevel region 22 is, for example, 1.5 mm, and the height of the step is, for example, 100 nm.

[0029] The element formation region 21 is a substantially circular region inside the bevel region 22 of the wafer 20. In the element formation region 21, a plurality of shots SH (SHw, SHp) are formed through a plurality of manufacturing processes. Each of these shots SH is an element that serves as a unit of individual processing in the manufacturing process of a semiconductor device. For example, in an imprint process, one shot SH is processed each time the template 10 is pressed once.

[0030] Of the shots SH, the normal shot SHw is a shot whose entire rectangular area is contained within the element formation region 21. Among the shots SH, the missing shot SHp is a shot whose part extends outside the element formation region 21. That is, the missing shot SHp is located on the outer periphery of the element formation region 21 and adjacent to the bevel region 22.

[0031] FIG. 3 is a diagram showing a process of forming a wafer 30 in the process of manufacturing the semiconductor device according to the first embodiment.

[0032] 3A shows a cross-sectional view of the wafer 20 at a predetermined chipped shot SHp and the bevel region 22. FIG. 3B shows a cross-sectional view of the wafer 20 at a predetermined chipped shot SHp and the bevel region 22.

[0033] 3(a), the wafer 20 includes a film to be processed 120 on a silicon substrate 100. The film to be processed 120 is a film to be processed, and is, for example, a single layer film such as a silicon oxide film or a silicon nitride film, or a laminated film in which multiple films are laminated.

[0034] 3(b), an SOC (Spin On Carbon) film 130 is formed on the processing target film 120. The SOC film 130 is a film formed by, for example, a spin coating method, and is an organic film containing carbon.

[0035] Next, an SOG (Spin On Glass) film 140 is formed on the SOC film 130. The SOG film 140 is a film formed by, for example, a spin coating method, and is an inorganic film such as a silicon oxide film.

[0036] Through the above processes, a wafer 30 to be subjected to the imprint process is formed.

[0037] At this time, the SOC film 130 and the SOG film 140 are formed to follow the element formation region 21 and the bevel region 22. Therefore, the SOG film 140 has a flat portion 141 that follows the element formation region 21, a side portion 142 that faces the outside of the wafer 30 along the step of the bevel region 22, and a bottom portion 143 that spreads from the lower end of the side portion 142 toward the edge 31 of the wafer 30. The flat portion 141 is a substantially circular region whose edge is defined by the side portion 142. Thereafter, a plurality of shots SH are processed on the flat portion 141 through a plurality of manufacturing processes.

[0038] FIG. 4 is a diagram showing a process of forming a liquid film of a first resist material 160 on a wafer 30 in the process of manufacturing the semiconductor device according to the first embodiment.

[0039] 4(a) and (b) show cross-sectional views of the wafer 30 at a predetermined chipped shot SHp and the bevel region 22. Also, Fig. 4(c) is a plan view of the wafer 30 corresponding to Fig. 4(b). Note that in each of Figs. 4(a) and (b), the side of the edge 31 of the wafer 30 is the outside of the wafer 30, and the opposite side is the inside of the wafer.

[0040] Fig. 4(a) is a diagram illustrating a process of forming a first resist material 160 on a wafer 30, and shows a process subsequent to the process of Fig. 3(b). First, as shown in Fig. 4(a), a coating device (not shown) is used to coat the first resist material 160 on the flat portion 141 of the SOG film 140. A spin coating method is used to coat the first resist material 160.

[0041] The spin coating method is a method in which droplets are supplied near the center of a substrate, and the substrate is rotated to spread the droplets to the outer periphery of the substrate, forming a liquid film. In the example of Fig. 4, a first resist material 160 is supplied from a nozzle NZ1 near the center of the wafer 30, and the wafer 30 is rotated. As a result, the first resist material 160 is spread, and the SOG film 140 is covered with the liquid film of the first resist material 160.

[0042] The first resist material 160 is a chemical liquid such as a resist that hardens when irradiated with light, and is assumed to have the same composition as the second resist material 170. The first resist material 160 is an example of a first photocurable resin.

[0043] Here, the reason why the spin coating method is used to form the liquid film of the first resist material 160 will be described. In the spin coating method, droplets supplied near the center of the substrate are spread by centrifugal force, so that the surface of the formed liquid film is generally flat. Therefore, when the template 10 is pressed against the surface of such a liquid film, the amount of air intervening between the template 10 and the surface of the liquid film can be reduced. Therefore, the liquid film can be quickly filled into the recesses of the template 10 without being hindered by air, and as a result, the processing time of the imprint process can be shortened.

[0044] Returning to Fig. 4(a), a coating device (not shown) supplies an organic solvent such as thinner from a nozzle NZ2 to the outer circumferential portion SR of the wafer 30 while continuing to rotate the wafer 30. As a result, as shown in Figs. 4(b) and 4(c), the first resist material 160 is dissolved and removed in the outer circumferential portion SR, a part of the SOG film 140 is exposed, and a peripheral portion BD of the first resist material 160 is formed. The peripheral portion BD is located inside the side portion 142 of the SOG film 140. The width L from the edge 31 of the wafer 30 to the peripheral portion BD is, for example, 2 to 3 mm.

[0045] Through the above processing, a liquid film of the first resist material 160 is formed in the central region CR of the wafer 30. The central region CR is a substantially circular region whose edge is defined by the peripheral edge BD.

[0046] Next, the wafer 30 on which the liquid film of the first resist material 160 has been formed is transferred to the inspection device 11 (FIG. 1).

[0047] The inspection device 11 inspects the wafer 30. Specifically, for example, the inspection device 11 images an area of ​​the wafer 30 that includes at least the outer circumferential portion SR. The inspection device 11 identifies position information of the peripheral portion BD and the side portion 142 based on the imaging result. The inspection device 11 generates measurement data that associates the identified position information of the peripheral portion BD with the position information of the side portion 142. The inspection device 11 transmits the measurement data to the control unit 90.

[0048] Next, the wafer 30 which has been inspected by the inspection apparatus 11 is transferred to the imprint apparatus 1 (FIG. 1).

[0049] 5 and 6 are diagrams showing an imprint process performed on a wafer 30 in the process of manufacturing the semiconductor device according to the first embodiment.

[0050] 5(a) and 6(a) to (d) show cross-sectional views of the wafer 30 in a predetermined chipped shot SHp and the bevel region 22. Also, FIG. 5(b) is a plan view of the wafer 30 corresponding to FIG. 5(a). FIG. 6 shows only the configuration of the imprint apparatus 1 described above that is involved in each process. In each of FIG. 5(a) and 6(a) to (d), the side of the edge 31 of the wafer 30 is the outside of the wafer 30, and the opposite side is the inside of the wafer.

[0051] Fig. 5(a) is a diagram illustrating a process of forming a second resist material 170 on the wafer 30, and shows a process subsequent to the process of Fig. 4(b). Prior to Fig. 5(a), the control unit 90 places the wafer 30 transferred from the inspection device 11 on the wafer stage 82 (Fig. 1). Then, the control unit 90 controls the wafer stage 82 to move the wafer 30 below the liquid dropping device 87.

[0052] The control unit 90 uses the liquid dropping device 87 to place droplets of the second resist material 170 in the outer circumferential region DR of the flat portion 141 of the SOG film 140. Specifically, the control unit 90 places the droplets of the second resist material 170 outside the first resist material 160 as the outer circumferential region DR. As a result, a resist layer 180x made of the first resist material 160 and the second resist material 170 is formed on the SOG film 140.

[0053] At this time, the control unit 90 determines the outer circumferential region DR based on the measurement data acquired from the inspection device 11. Specifically, based on position information of the peripheral portion BD included in the measurement data and position information of the side portion 142 of the SOG film 140, the control unit 90 specifies the region from the side portion 142 to the peripheral portion BD as the outer circumferential region DR in which the droplets of the second resist material 170 are to be placed.

[0054] 5(a) and 5(b), the control unit 90 also drops the second resist material 170 in an annular shape in an area that is a width W inward from the boundary between the central area CR and the outer peripheral area DR. The width W is not particularly limited, but is assumed to be equal to or less than the width of one droplet of the second resist material 170. The width of one droplet is, for example, 10 μm or less.

[0055] As a result, the first resist material 160 and the second resist material 170 are vertically overlapped near the boundary between the central region CR and the peripheral region DR. As a result, a continuous resist layer 180x is formed without any gaps between the first resist material 160 and the second resist material 170.

[0056] In addition, the above-mentioned process of identifying the outer circumferential region DR by the control unit 90 may be performed at a predetermined timing after the control unit 90 acquires measurement data from the inspection apparatus 11 and before the control unit 90 starts placing droplets of the second resist material 170.

[0057] When the placement of the droplets of the second resist material 170 is completed, the control unit 90 moves the wafer 30 below the template 10 as shown in FIG. 6(a).

[0058] 6B, the control unit 90 presses the template 10 against the resist layer 180x. Then, the resist layer 180x fills the recesses of the pattern 10p so as to follow the unevenness of the pattern 10p of the template 10.

[0059] As shown in FIG. 6(c), when the recesses of the template 10 are filled with the resist layer 180x, the control unit 90 irradiates the template 10 with ultraviolet light Le from above while maintaining the template 10 pressed against the resist layer 180x. The ultraviolet light Le has a wavelength in a wavelength range to which the resist layer 180x can be photosensitive. The ultraviolet light Le passes through the transparent template 10 and is irradiated onto the resist layer 180x. This hardens the resist layer 180x. The amount of irradiation of the ultraviolet light Le at this time is preferably an amount of irradiation that completely hardens the resist layer 180x. Note that, the completely hardened state referred to here refers to, for example, a state in which the resist layer 180x is hardened to an extent that it can be released from the template 10 or to an extent that it can function as an etching mask for the SOG film 140.

[0060] As shown in FIG. 6(d), the control unit 90 releases the template 10 from the resist layer 180x. As a result, a resist pattern 180p is formed. The resist pattern 180p has a pattern that is an inversion of the pattern 10p of the template 10. Furthermore, a resist residual film 180r is formed in the recesses between the protruding patterns of the resist pattern 180p. This is because, when the template 10 was pressed, the protruding portions of the pattern 10p of the template 10 were maintained slightly above the bottom surface of the resist layer 180x.

[0061] With the above, the imprint processing performed on the predetermined missing shot SHp of the wafer 30 is completed.

[0062] FIG. 7 is a diagram showing a process for processing the processing target film 120 in the process of manufacturing the semiconductor device according to the first embodiment.

[0063] 7(a) to (d) show cross-sectional views of a wafer 30 in a predetermined chipped shot SHp and a bevel region 22. FIG.

[0064] As shown in Fig. 7(a), the resist pattern 180p formed by the imprint process has the above-mentioned resist residual film 180r. Therefore, first, the resist residual film 180r is removed, and the SOG film 140 is etched using the resist pattern 180p as a mask. Then, the SOG pattern 140p is formed as shown in Fig. 7(b).

[0065] Next, the SOC film 130 is etched using the SOG pattern 140p as a mask to form the SOC pattern 130p as shown in Fig. 7(c). The resist pattern 180p is an organic film similar to the SOC pattern 130p. Therefore, the resist pattern 180p disappears in this process.

[0066] Next, the processed film 120 is etched using the SOC pattern 130p as a mask to form a patterned processed film 120p as shown in Fig. 7(d) At this time, the SOC pattern 130p is removed by ashing using oxygen plasma.

[0067] In this manner, a film to be processed 120p on which a pattern is formed can be obtained. After this, various manufacturing steps are further carried out to manufacture the semiconductor device of the first embodiment.

[0068] (Comparative Example) A method for manufacturing a semiconductor device according to a comparative example of embodiment 1 will now be described with reference to Figures 13 and 14. Figures 13 and 14 are diagrams illustrating a part of a process for manufacturing a semiconductor device according to the comparative example.

[0069] 13(a) to 13(c) show a cross-sectional view of a predetermined chipped shot SHp after a resist layer 180y has been formed on the wafer 30, and the wafer 30 in the bevel region 22. Also, FIG. 13(d) is a cross-sectional view of a normal shot SHw to be imprinted next to the chipped shot SHp. In each of FIG. 13(a) to 13(c), the side of the edge 31 of the wafer 30 is the outside of the wafer 30, and the opposite side is the inside of the wafer.

[0070] In the comparative example of the semiconductor device manufacturing method, the resist layer 180y is formed by spin coating. At this time, the position of the peripheral portion BDx of the resist layer 180y may vary in the circumferential direction of the wafer 30. This is because the supply position of the organic solvent to the wafer 30 varies in the circumferential direction. Such variation in the supply position of the organic solvent to the wafer 30 may occur due to the eccentric rotation of the wafer 30.

[0071] Specifically, as shown in Fig. 13(a), the peripheral portion BDx of the resist layer 180y may protrude outward from the side portion 142 by, for example, about 50 um. As shown in Fig. 13(b), when the template 10 is pressed against such a wafer 30, as shown in Fig. 13(c), a part of the resist layer 180y may adhere to the template 10 and contaminate the template 10 when the template 10 is released. When such a template 10 is used to perform an imprint process on a normal shot SHw to be processed next, as shown in Fig. 13(d), a so-called carryover defect may occur in which a contaminated portion of the template 10 is transferred to the shot SH.

[0072] 14, for example, the peripheral portion BDx of the resist layer 180y may be located inside the side portion 142. When the template 10 is pressed against such a wafer 30, the template 10 may come into contact with the flat portion 141 of the SOG 140 in an area X outside the peripheral portion BDx. At this time, a shear force generated between the template 10 and the SOG 140 may deteriorate the alignment accuracy of the template 10. As a result, defects such as poor pattern formation may occur.

[0073] The variation in the position of the peripheral edge BDx as described above is within ±100 μm in the circumferential direction of the wafer 30. Furthermore, such variation in the position of the peripheral edge BDx often differs depending on the coating apparatus. That is, for example, the positions of the peripheral edges BDx of the wafers 30 processed by the same coating apparatus often end up being the same.

[0074] (Action and effect) According to the imprint method of the first embodiment, a first resist material 160 is applied to a central region CR of the wafer 30 to form a liquid film of the first resist material 160, and droplets of a second resist material 170 are placed in a peripheral region DR of the wafer 30. Then, the template 10 is pressed against a resist layer 180 made of the first resist material 160 and the second resist material 170. In this way, a pattern is formed.

[0075] In this way, by disposing droplets of the second resist material 170 in the peripheral region DR of the wafer 30, the resist layer 180x to be imprinted can be formed with high accuracy inside the side surface portion 142 of the SOG film 140, i.e., on the flat surface portion 141 to be processed by the shot SH. This suppresses contamination of the template 10 and deterioration of alignment accuracy, thereby reducing defects such as carryover defects and pattern formation failures. As a result, it is also possible to improve the semiconductor yield and reduce manufacturing costs.

[0076] Furthermore, at this time, after the application of the first resist material 160, droplets of the second resist material 170 are placed outside the first resist material 160 as the outer circumferential region DR. In this way, after the application of the first resist material 160, the process of dispensing droplets of the second resist material 170 and the process of transferring the template 10 are performed successively in the same imprint apparatus 1, thereby making it possible to shorten the processing time required for manufacturing the semiconductor device.

[0077] Furthermore, position information of the peripheral portion BD of the first resist material 160 is obtained, and droplets of the second resist material 170 are placed based on the position information. Since the droplets of the second resist material 170 can be placed after grasping the position information of the first resist material 160 in this way, the resist layer 180x can be formed more densely and accurately on the flat surface portion 141. As a result, defects can be further reduced.

[0078] [Variations] A modified example of the first embodiment will be described in detail with reference to Fig. 8. The imprint method of the modified example differs from the above-mentioned embodiment in that the application of the first resist material 160 is performed after the placement of droplets of the second resist material 170. In the following, the same components as those of the first embodiment will be denoted by the same reference numerals, and the description thereof may be omitted.

[0079] 8A and 8B are diagrams showing processes performed on a wafer 30 in the process of manufacturing a semiconductor device according to a modified example of embodiment 1. Figures 8A and 8B show cross-sectional views of a wafer in a predetermined chipped shot SHp and a bevel region 22.

[0080] Prior to the process of FIG. 8, the wafer 30 that has been subjected to the process of FIG.

[0081] Next, as shown in FIG. 8( a ), the control unit 90 uses the liquid dropping device 87 to place droplets of the second resist material 170 on the outer periphery region DR of the wafer 30 .

[0082] At this time, the control unit 90 determines the above-mentioned outer circumferential region DR based on the measurement data stored in the storage unit 91.

[0083] As described above, the memory unit 91 previously stores the measurement data of the wafer 30 in association with information on the coating apparatus that processed the wafer 30. The control unit 90 acquires the measurement data corresponding to the coating apparatus used in the subsequent process from the memory unit 91, and determines the outer circumferential region DR based on the measurement data. This is because the positions of the peripheries BDx of the wafers 30 processed by the same coating apparatus are often the same. In this way, the control unit 90 places the droplets of the second resist material 170 after assuming the positions of the peripheries BDx of the first resist material 160 that will be coated in the subsequent process based on the measurement data.

[0084] Next, as shown in FIG. 8(b), the second resist material 170 is irradiated with ultraviolet light Lf using a light source 89. The ultraviolet light Lf has a wavelength in a wavelength range to which the second resist material 170 can be photosensitive. The amount of irradiation of the ultraviolet light Lf at this time is preferably an amount of irradiation to the extent that the second resist material 170 is semi-cured. Note that the semi-cured state here refers to a state in which the viscosity of the second resist material 170 has increased and the second resist material 170 has not yet completely cured. This suppresses the volatilization of the second resist material 170, and prevents its deterioration. This also makes the second resist material 170 insoluble in the first resist material 160 and organic solvents described below.

[0085] Next, the wafer 30 on which the dropping of the second resist material 170 has been completed is transported to the above-mentioned coating device (not shown). Then, as shown in FIG. 8(c), the first resist material 160 is coated on the flat portion 141 of the SOG film 140 to form a liquid film.

[0086] At this time, the first resist material 160 covers the droplets of the second resist material 170. Therefore, by supplying an organic solvent to the outer circumferential portion SR using the nozzle NZ2, the second resist material 170 in the outer circumferential region DR is exposed. As a result, as shown in FIG. 8(d), a liquid film of the first resist material 160 is formed inside the droplets of the second resist material 170 as the central region CR.

[0087] 8(d), the control unit 90 supplies the organic solvent to a region that is a predetermined width outside the boundary between the central region CR and the peripheral region DR. As a result, the first resist material 160 and the second resist material 170 overlap each other vertically near the boundary between the central region CR and the peripheral region DR. The predetermined width is, for example, 100 um or more.

[0088] Thereafter, the processes from FIG. 6(a) onward in the first embodiment are carried out.

[0089] (Action and effect) According to the manufacturing method of the semiconductor device of the modified example, the resist layer 180x can be formed densely and accurately on the flat portion 141, thereby reducing defects.

[0090] [Embodiment 2] Hereinafter, the second embodiment will be described in detail with reference to FIGS.

[0091] The method for manufacturing a semiconductor device according to the second embodiment differs from the first embodiment in that the positions of droplets of the second resist material 170 are determined based on the layout of the template 10. In the following description, the same reference numerals are used to designate the same components as those in the first embodiment, and the description thereof may be omitted.

[0092] Fig. 9 is a diagram showing an example of the configuration of an imprint apparatus 2 according to embodiment 2. As shown in Fig. 9, a design apparatus 12 is connected to a control unit 90 of the imprint apparatus 2.

[0093] At the beginning of the manufacturing process of the semiconductor device, the design device 12 generates design information such as a design of the semiconductor device and a layout of the template 10 based on the design of the semiconductor device. The design information includes information on the dimensions of the projections and recesses of the pattern 10p of the template 10 and the arrangement position as the layout of the template 10. The design information also includes a coverage map M, which will be described later. The design device 12 transmits such design information to the control unit 90 of the imprint apparatus 1.

[0094] FIG. 10 is a schematic diagram showing an example of a coverage map M according to the second embodiment. The coverage map M indicates the magnitude of the coverage of the template 10 by different colors. For example, in the coverage map M, the areas WR1 to WR3 shown in white indicate areas where the coverage is equal to or less than a predetermined threshold. On the other hand, the areas BR1 to BR2 shown in black indicate areas where the coverage is greater than the predetermined threshold. The predetermined threshold is, for example, 20%. That is, for example, the areas WR1 to WR3 are areas where the coverage is equal to or less than 20%. The coverage indicates the proportion of the area occupied by the recesses to the predetermined area where the pattern 10p of the template 10 is formed. For example, a small coverage indicates that the area of ​​the recesses per predetermined area is large.

[0095] The control unit 90 determines the placement position of the second resist material 170 based on such a coverage map M. The second resist material 170 is an example of a first photocurable resin.

[0096] (Method of manufacturing a semiconductor device) Next, an example of a method for manufacturing a semiconductor device including an imprint process using the imprint apparatus 2 of the second embodiment will be described with reference to FIG.

[0097] Fig. 11 is a diagram showing processing performed on a wafer 30 in the process of manufacturing a semiconductor device according to embodiment 2. Fig. 11(a) to (d) show cross-sectional views of the wafer at a predetermined normal shot SHw. Note that in embodiment 2, the processing in Figs. 3(a) and (b) and the processing in Fig. 6(b) and after in embodiment 1 are also performed.

[0098] First, prior to the process of FIG. 11, the wafer 30 that has been subjected to the process of FIG.

[0099] Then, as shown in FIG. 11( a ), the control unit 90 uses the liquid dropping device 87 to place droplets of the second resist material 170 on the flat surface portion 141 of the SOG film 140 .

[0100] At this time, the control unit 90 determines the placement positions of the droplets of the second resist material 170 on the flat surface portion 141 based on the coverage map M. Specifically, for example, the control unit 90 determines an area WRW1 on the flat surface portion 141 corresponding to an area WR1 of the template 10 in which the coverage is equal to or less than a predetermined threshold, as the placement positions of the droplets of the second resist material 170.

[0101] 11(b), the second resist material 170 is irradiated with ultraviolet light Lf using a light source 89. The amount of irradiation of the ultraviolet light Lf at this time is preferably such that the second resist material 170 is semi-cured.

[0102] Next, the wafer 30 which has been irradiated with the ultraviolet light Lf is transported to a coating device (not shown). Then, as shown in FIG. 11(c), the first resist material 160 is coated on the wafer 30 to form a liquid film. As a result, the flat portion 141 containing the droplets of the second resist material 170 is covered with the liquid film of the first resist material 160. In this manner, a resist layer 180x consisting of the first resist material 160 and the second resist material 170 is formed. The first resist material 160 is an example of a second photocurable resin.

[0103] At this time, in the region WRW1, the second resist material 170 and the first resist material 160 are vertically overlapped with each other, so that the amount of the resist layer 180x formed in the region WRW1 is greater than that in the regions other than the region WRW1.

[0104] 11(d), the control unit 90 moves the wafer 30 below the template 10. Then, the region WRW1 on the flat portion 141 and the region WR1 of the template 10 face each other in the vertical direction. Thereafter, when the template 10 is pressed against the resist layer 180x, the resist layer 180x in the region WRW1 fills the recesses in the region WR1 of the template 10.

[0105] Thereafter, the processes in and after FIG. 6(b) in the above embodiment are carried out.

[0106] (Comparative Example) A method for manufacturing a semiconductor device according to a comparative example of the second embodiment will be described with reference to Fig. 15. Fig. 15 is a diagram illustrating a part of a process for manufacturing a semiconductor device according to the comparative example.

[0107] 15(a) and 15(b) show cross-sectional views of a wafer in a predetermined normal shot SHw on which a resist layer 180z of the comparative example is formed.

[0108] As shown in FIG. 15(a), the thickness of the resist layer 180z formed by the spin coating method is approximately uniform on the flat portion 141. When the template 10 is pressed against such a wafer 30, as shown in FIG. 15(b), for example, in an area WR1 where the coverage of the template 10 is small, the resist layer 180z may not fill the recesses sufficiently, forming voids V in the resist layer 180z. This is because the amount of the resist layer 180z filling the recesses is insufficient because the area of ​​the recesses per given area of ​​the template 10 is large. Such voids V may cause defects such as pattern loss.

[0109] Therefore, for example, the thickness of the resist layer 180z may be increased in order to increase the filling amount of the resist layer 180z in the region WR1. However, in this case, the thickness of the resist residual film 180r may increase when the template 10 is pressed against the resist layer 180z. This may narrow the process margin when processing the processing target film 120.

[0110] (Action and effect) In the imprint method of the second embodiment, the positions of droplets of the second resist material 170 are determined based on the coverage of the template 10 to be transferred to the wafer 30. The first resist material 160 is applied to the wafer 30 on which the second resist material 170 is arranged, and the template 10 is pressed against a resist layer 180x consisting of the first resist material 160 and the second resist material 170. In this way, a pattern is formed.

[0111] This allows the resist layer 180 to be sufficiently filled into the recesses of the template 10 regardless of the coverage of the template 10, thereby reducing defects such as pattern loss. As a result, it is also possible to improve the semiconductor yield and reduce the manufacturing cost.

[0112] Furthermore, droplets of the second resist material 170 are placed at positions on the wafer 30 corresponding to the locations where the coverage is equal to or less than a predetermined threshold value. This allows the resist layer 180 to be sufficiently filled in recesses in areas of the template 10 with a low coverage, further reducing defects.

[0113] Before applying the first resist material 160, the second resist material 170 is irradiated with light having a wavelength in a wavelength range to which the second resist material 170 can be photosensitive. This makes it possible to prevent the second resist material 170 from volatilizing, thereby suppressing its deterioration.

[0114] [Variations] A modified example of the second embodiment will be described in detail with reference to Fig. 12. The modified imprint method and semiconductor device manufacturing method differ from the second embodiment in that the first resist material 160 is applied before the droplets of the second resist material 170 are placed. Note that in the following, the same reference numerals are used to designate the same components as those in the second embodiment, and the description thereof may be omitted.

[0115] Fig. 12 is a diagram showing processing performed on a wafer 30 in the process of manufacturing a semiconductor device according to a modified example of embodiment 2. Fig. 12(a) and (b) show cross-sectional views of the wafer at a predetermined normal shot SHw. Note that in the modified example, the processing in Fig. 3(a) and (b) in embodiment 1 and the processing in Fig. 6(a) and thereafter are also performed.

[0116] First, as shown in FIG. 12(a), a first resist material 160 is applied to the wafer 30 using a coating device (not shown).

[0117] 12(b), the control unit 90 places droplets of the second resist material 170 in an area WRW1 on the flat surface portion 141. At this time, the control unit 90 determines the area WRW1 based on the coverage map M.

[0118] Thereafter, the processes in and after FIG. 6(a) in the above embodiment are carried out.

[0119] (Action and effect) According to the manufacturing method of the semiconductor device of the modified example, the same effects as those of the manufacturing method of the semiconductor device of the above-mentioned second embodiment are achieved.

[0120] (Other variations) In the above-described first embodiment, the dropping position of the second resist material 170 is determined based on the result of inspecting the wafer 30 coated with the first resist material 160 by the inspection device 11, but the present invention is not limited to this. For example, the dropping position of the second resist material 170 may be determined by monitoring the shear force for each shot when the template 10 is pressed against the wafer 30. That is, for example, in a shot where the shear force is equal to or greater than a predetermined value, it is determined that the resist layer 180 is not formed between the template 10 and the wafer 30. Then, in the wafer 30 to be processed next, the shot may be determined as the dropping position of the second resist material 170.

[0121] In the above-described embodiment and modified examples, the wafers 20 and 30 have the bevel region 22, but this is not limiting. For example, the wafers 20 and 30 may be flat substrates without steps.

[0122] In the above-described embodiment and modified examples, it is assumed that the first resist material 160 and the second resist material 170 have the same composition, but this is not limited thereto. For example, the first resist material 160 and the second resist material 170 may have different compositions.

[0123] The above-described embodiments and modifications can be combined in any manner.

[0124] Although some embodiments and modifications of the present invention have been described, the above-mentioned embodiments and modifications are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These novel embodiments and modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0125] 1, 2...imprint apparatus, 10...template, 11...inspection apparatus, 12...design apparatus, 20, 30...wafer, 90...control unit, 100...silicon substrate, 120...film to be processed, 130...SOG film 140...SOG film, 160...first resist material, 170...second resist material, 180x, 180y, 180z...resist layer, 180p...resist pattern, BD...periphery, CR...central region, DR...peripheral region, Le, Lf...ultraviolet light, M...coverage map, WRW1...region.

Claims

1. applying a first photocurable resin to a central region of a substrate to form a liquid film of the first photocurable resin; Placing droplets of a second photocurable resin on the peripheral region of the substrate; pressing a template against the first and second photocurable resins; irradiating light to cure the first and second photocurable resins; Releasing the template from the first and second photocurable resins to form a pattern on the substrate. Imprinting method.

2. The first photocurable resin is applied by a spin coating method, The disposing of the droplets of the second photocurable resin includes using an inkjet method. The imprint method according to claim 1 .

3. Disposing the droplet of the second photocurable resin includes: and disposing droplets of the second photocurable resin on the outer periphery of the first photocurable resin after applying the first photocurable resin. The imprint method according to claim 1 .

4. acquiring position information of a peripheral portion of the first photocurable resin; disposing the droplets of the second photocurable resin based on the position information; The imprint method according to claim 3 .

5. The formation of the liquid film of the first photocurable resin includes: and applying the first photocurable resin to an inner side of the droplet of the second photocurable resin as the central region after disposing the droplet of the second photocurable resin. The imprint method according to claim 1 .

6. Before applying the first photocurable resin, Irradiating the second photocurable resin with light having a wavelength in a wavelength range to which the second photocurable resin is sensitive. The imprint method according to claim 5 .

7. determining positions of droplets of a first photocurable resin on a substrate based on a coverage of a pattern of the template to be transferred to the substrate; Applying a second photocurable resin to the substrate on which the first photocurable resin is disposed; pressing the template against the first and second photocurable resins; irradiating light to cure the first and second photocurable resins; Releasing the template from the first and second photocurable resins to form the pattern on the substrate. Imprint method.

8. Applying the second photocurable resin to the substrate includes: applying the second photocurable resin to the substrate containing the first photocurable resin after depositing the droplet of the first photocurable resin; The imprint method according to claim 7 .

9. Disposing the droplet of the first photocurable resin includes: After the application of the second photocurable resin, disposing a droplet of the first photocurable resin on the substrate containing the second photocurable resin; The imprint method according to claim 7 .

10. placing droplets of the first photocurable resin at positions on the substrate corresponding to the locations where the coverage is equal to or less than a predetermined threshold; The imprint method according to claim 7 .

11. Before applying the second photocurable resin, Irradiating the first photocurable resin with light having a wavelength in a wavelength range to which the first photocurable resin is sensitive. The imprint method according to claim 8 .

12. A film to be processed is formed on a substrate, applying a first photocurable resin to a central region of the substrate to form a liquid film of the first photocurable resin; Placing droplets of a second photocurable resin on the peripheral region of the substrate; pressing a template against the first and second photocurable resins; irradiating light to cure the first and second photocurable resins; Releasing the template from the first and second photocurable resins to form a pattern on the processing target film; The film to be processed is processed using the pattern as a mask; manufacturing a semiconductor device using the processed film; A method for manufacturing a semiconductor device.

13. A film to be processed is formed on a substrate, determining positions of droplets of a first photocurable resin on the substrate based on a coverage of a pattern of a template pressed against the substrate; Applying a second photocurable resin to the substrate on which the first photocurable resin is disposed; pressing the template against the first and second photocurable resins; irradiating light to cure the first and second photocurable resins; Releasing the template from the first and second photocurable resins to form the pattern on the workpiece film; The film to be processed is processed using the pattern as a mask; manufacturing a semiconductor device using the processed film; A method for manufacturing a semiconductor device.

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