Imprint apparatus, imprint method, and method for manufacturing a semiconductor device

Abstract

To prevent template corruption. [Solution] The imprint apparatus of the embodiment is an imprint apparatus that performs an imprint process to form a resin film on a substrate having a plurality of shot regions and to press a template onto the resin film to form a pattern, and comprises a control unit that controls the imprint process, and the control unit changes the residual film thickness, which is the thickness of the resin film at the bottom surface of the recess of the pattern, based on the particle size of foreign matter present on the substrate.

Description

Technical Field

[0001] Embodiments of the present invention relate to an imprint apparatus, an imprint method, and a method of manufacturing a semiconductor device.

Background Art

[0002] In the manufacturing process of a semiconductor device, an imprint process is used. In the imprint process, an operation of pressing a template having a pattern formed thereon against a substrate is performed. At this time, if foreign matter exists on the substrate, the template may be damaged.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] One embodiment aims to provide an imprint apparatus, an imprint method, and a method of manufacturing a semiconductor device that can suppress damage to a template.

Means for Solving the Problems

[0005] The imprint apparatus according to the embodiment forms a resin film on a substrate having a plurality of shot regions, and performs an imprint process of pressing a template against the resin film to form a pattern. The imprint apparatus includes a control unit that controls the imprint process. The control unit changes a remaining film thickness, which is the thickness of the resin film at the bottom surface of the concave portion of the pattern, based on the particle size of foreign matter present on the substrate.

Brief Description of the Drawings

[0006] [Figure 1] A schematic diagram showing an example of the configuration of a template according to the embodiment. [Figure 2] A schematic diagram showing an example of the substrate configuration according to the embodiment. [Figure 3] A schematic diagram showing an example configuration of an imprint device according to an embodiment. [Figure 4] A diagram showing an example of the layout of multiple templates according to the embodiment. [Figure 5] A diagram illustrating an example of the operation of an imprint device in the imprint process according to the embodiment. [Figure 6] Correlation data showing the relationship between the particle size of foreign matter and the minimum remaining film thickness required to suppress template damage. [Figure 7] A diagram showing the shot area and the corresponding template side by side according to the embodiment. [Figure 8] A flowchart illustrating the flow of the imprint process performed in the imprint device according to the embodiment. [Modes for carrying out the invention]

[0007] Embodiments will be described in detail below with reference to the drawings. However, the present invention is not limited to the embodiments described below. Furthermore, the components in the embodiments described below include those that are easily conceivable by those skilled in the art or that are substantially identical.

[0008] (Examples of template and wafer configurations) In imprint processing, the pattern of the template is transferred to the resist on the substrate by pressing the template, which has a fine pattern formed on it, against the resist on the substrate. The resist is an example of a resin film that is placed on a substrate to form a pattern on it.

[0009] The configuration of the template 10 and substrate 20 of the embodiment will be described below with reference to Figures 1 and 2.

[0010] Figure 1 is a schematic diagram showing an example of the configuration of the template 10 according to the embodiment. Figure 1(a) is a plan view of the template 10, Figure 1(b) is a cross-sectional view along the line A-A' in Figure 1(a), and Figure 1(c) is a partially enlarged view of the mesa portion 15 in Figure 1(a). However, hatching is omitted in Figure 1(b) for the sake of clarity.

[0011] The template 10 is made of a transparent material such as quartz glass. As shown in Figures 1(a) and (b), the template 10 includes, for example, a rectangular template substrate 14. A mesa portion 15 is provided on the surface of the template substrate 14, and a counterbore 16 is provided on the back surface.

[0012] The mesa portion 15 is located in the center of the template substrate 14 and has, for example, a rectangular shape. The mesa portion 15 has a transfer surface 15s that is pressed against the resist on the substrate 20 in a single pressing operation.

[0013] As shown in Figure 1(c), the transfer surface 15s is provided with eight chip pattern regions 15c-1 to 15c-8, each of which has a nano-order-size fine pattern 15p formed on it. The fine pattern 15p may be, for example, a pattern with multiple grooves, a pattern with multiple dots, etc. The transfer surface 15s may also be provided with alignment marks or the like.

[0014] However, the configuration of template 10 shown in Figures 1(a) to (c) is merely an example and is not limited to this. The number and arrangement of chip pattern areas 15c are arbitrary.

[0015] From this point forward, if chip pattern areas 15c-1 to 15c-8 are not individually distinguished, they may be referred to as chip pattern area 15c.

[0016] FIG. 2 is a schematic diagram showing an example of the configuration of the substrate 20 according to the embodiment. FIG. 2(a) is a plan view of the substrate 20, and FIG. 2(b) is a partial enlarged view of the shot region 25SH in FIG. 2(a).

[0017] As shown in FIG. 2(a), the upper surface of the substrate 20 is partitioned into a plurality of shot regions 25SH. The plurality of shot regions 25SH are arranged in a grid pattern over substantially the entire surface of the substrate 20. These shot regions 25SH are regions that serve as the processing unit per application in some of the manufacturing processes of the semiconductor device, including the imprint process. That is, in the imprint process, the transfer surface 15s of the template 10 is pressed against each shot region 25SH.

[0018] As shown in FIG. 2(b), chip regions 25c-1 to 25c-8 are provided in each of the plurality of shot regions 25SH. The chip regions 25c-1 to 25c-8 are regions that are diced into chips at the end of the manufacturing process of the semiconductor device. Element portions 25p are provided in the chip regions 25c-1 to 25c-8, respectively. Alignment marks or the like may be provided outside the element portions 25p.

[0019] In a state where the substrate 20 and the template 10 are aligned, for example, the chip regions 25c-1 to 25c-8 are arranged at positions that fit within the transfer surface 15s of the template 10. That is, one chip region 25c of the substrate 20 is an area substantially equal to one chip pattern region 15c of the template 10. And by one pressing operation, the fine pattern 15p of the chip pattern region 15c is transferred to the element portion 25p of the chip region 25c. That is, the element portion 25p of the chip region 25c is arranged at a position facing the fine pattern 15p of the chip pattern region 15c.

[0020] However, the configuration of the substrate 20 shown in FIGS. 2(a) and (b) is merely an example and is not limited thereto. The configuration of the substrate 20 can be changed together with the configuration of the template 10.

[0021] From this point forward, unless chip regions 25c-1 to 25c-8 are individually distinguished, each of them may be referred to simply as chip region 25c.

[0022] (Example configuration of imprint device 1) Figure 3 is a schematic diagram showing an example of the configuration of the imprint device 1 according to an embodiment.

[0023] As shown in Figure 3, the imprint apparatus 1 comprises a template stage 81, a wafer stage 82, image sensors 83 and 84, a reference mark 85, an alignment unit 86, a liquid dropper 87, a stage base 88, a light source 89, an inspection unit 90, a control unit 91, and a template storage unit 93. A template 10 is also mounted on the imprint apparatus 1.

[0024] The wafer stage 82 includes wafer chucks 82b, 82c, and a main body 82a. The wafer chucks 82b and 82c are respectively placed on substrates 20a and 20b that are to be imprinted. Substrates 20a and 20b may be semiconductor substrates including silicon wafers, insulating substrates, or conductive substrates. Substrate 20b is the substrate that will be imprinted after substrate 20a.

[0025] The wafer chucks 82b and 82c are arranged adjacent to each other on the main body 82a of the wafer stage 82 and are configured as suction chucks that attract the substrates 20a and 20b to predetermined positions on the main body 82a, respectively.

[0026] A reference mark 85 is provided on the wafer stage 82. The reference mark 85 is used for alignment when loading substrate 20a or 20b onto the wafer stage 82.

[0027] The wafer stage 82 places the substrates 20a and 20b on it and moves within a parallel plane (horizontal plane). For example, when inspecting the substrates 20a and 20b for foreign matter and when dropping resist onto the substrates 20a and 20b, the wafer stage 82 moves each of the substrates 20a and 20b to the side below the inspection unit 90 or the liquid dropping device 87. When performing imprint processing on the substrates 20a and 20b, the wafer stage 82 moves each of the substrates 20a and 20b to the side below the template 10.

[0028] From this point forward, if boards 20a and 20b are not distinguished individually, they may be referred to simply as board 20.

[0029] The stage base 88 supports the template 10 by the template stage 81 and moves vertically. This enables the stamping operation.

[0030] An alignment unit 86 equipped with multiple image sensors 83 is provided on the stage base 88. The alignment unit 86 detects the position of the substrate 20 and the template 10 based on alignment marks provided on the substrate 20 and the template 10, respectively.

[0031] The alignment unit 86 includes a detection system 86a and an illumination system 86b. The illumination system 86b shines light on the substrate 20 and the template 10 to make the alignment marks formed on them visible. The detection system 86a detects the images of the alignment marks and aligns their positions to align each of the substrates 20 with the template 10.

[0032] The detection system 86a and the illumination system 86b each include mirrors 86x and 86y, such as dichroic mirrors, as imaging units. The mirrors 86x and 86y use light from the illumination system 86b to form images from the substrate 20, such as alignment marks, and the template 10.

[0033] Specifically, the light Lb from the illumination system 86b is reflected by the mirror 86y downwards towards where the substrate 20 is located. The light La from the substrate 20 is reflected by the mirror 86x toward the detection system 86a. In addition, some of the light Lc from the substrate 20, etc., passes through the mirrors 86x and 86y and travels toward the image sensor 83 above.

[0034] The image sensor 83 captures a portion of this light Lc as an image including alignment marks, etc. The image captured by the image sensor 83 is analyzed by the control unit 91 in order to align the substrate 20 with the template 10.

[0035] On the other hand, the light La reflected by the mirror 86x toward the detection system 86a proceeds toward the image sensor 84 of the detection system 86a.

[0036] The image sensor 84 captures the light La reflected by the mirror 86x as an image including alignment marks, etc. The image captured by the image sensor 84 is analyzed by the control unit 91 in order to align the substrate 20 and the template 10.

[0037] The droplet dispensing device 87 is a device that drops resist onto the substrate 20 using an inkjet method. The inkjet head of the droplet dispensing device 87 has multiple fine holes for ejecting droplets of resist, and based on the drop recipe generated in the control unit 91, it drops droplets of resist onto each shot area 25SH on the substrate 20.

[0038] The light source 89 is a device that irradiates light, such as ultraviolet light, to cure the resist, and is located above the stage base 88. The light source 89 irradiates light from above the template 10 while the template 10 is pressed against the resist.

[0039] The inspection unit 90 is a foreign object inspection device that irradiates the substrate 20 placed on the wafer stage 82 with a laser or the like and inspects for foreign objects on the substrate 20 based on the intensity of the scattered light. The inspection unit 90 inspects the presence or absence of foreign objects over substantially the entire surface of the substrate 20 before the resist is dropped and outputs inspection data. The inspection data includes information on the particle size of the foreign objects present on the substrate 20, and information on the location of the foreign objects. The location information of the foreign objects includes, for example, the shot area 25SH where the foreign objects are present, the chip area 25c where the foreign objects are present, and the coordinates of the foreign objects on the substrate 20. The inspection data is analyzed by the control unit 91 in order to create a drop recipe. The particle size of the foreign objects is an example of the size of the foreign objects. The particle size is, for example, the diameter of the foreign object. Note that the detection unit 90 may be provided outside the imprint apparatus 1.

[0040] The control unit 91 is configured as a computer equipped with, for example, a hardware processor such as a CPU (Central Processing Unit), memory, and an HDD (Hard Disk Drive). The control unit 91 controls the imprint process, including the first and second control processes described later, according to the program. The control unit 91 executes the imprint process by controlling the template stage 81, wafer stage 82, reference marks 85, alignment unit 86 including image sensors 83 and 84, liquid drop dispenser 87, stage base 88, light source 89, inspection unit 90, and template storage unit 93.

[0041] The memory of the control unit 91 stores, for example, the program executed by the CPU of the control unit 91, and various control parameters necessary for the operation of the CPU. The HDD of the control unit 91 stores, for example, various information related to the multiple templates 10 held in the template storage unit 93 and the circuit board 20. This information includes, for example, design data including the layout information of each of the multiple templates 10, design data for the circuit board 20, and inspection data of the circuit board 20 output from the inspection unit 90.

[0042] The template storage unit 93 stores multiple templates 10 that can be mounted on the imprint device 1. The template storage unit 93 determines, by the control unit 91, to be the template 10 to be used for the imprint process from among the multiple templates 10. The template 10 determined to be used for the imprint process is transported from the template storage unit 93 to the template stage 81 and mounted according to the instructions of the control unit 91.

[0043] Figure 4 shows an example of the layout of multiple templates according to the embodiment. However, for convenience, in Figure 4, only the configuration of the transfer surface 15s of each template 10 is shown, and the other configurations are omitted.

[0044] As shown in Figure 4, the template storage unit 93 stores templates 10-1 to 10-p (where p is an integer of 1 or more). Among templates 10-1 to 10-p, some templates, such as templates 10-2 to 10-p, have invalid regions R set on their transfer surfaces 15s that should not be used for pattern formation. The invalid regions R are set in units of 1 or more for each of templates 10-2 to 10-p, with the chip pattern area 15c being one unit. Furthermore, the position of these invalid regions differs for each template 10.

[0045] For example, in template 10-2, of the chip pattern areas 15c-1 to 15c-8, chip pattern area 15c-1 is set as an invalid area R, and in template 10-3, chip pattern area 15c-2 is set as an invalid area R. Also, for example, in template 10-4, four chip pattern areas 15c-2, 15c-3, 15c-6, and 15c-7 are set as invalid areas R, and in template 10-p, two chip pattern areas 15c-4 and 15c-8 are set as invalid areas R.

[0046] For example, a portion of the fine pattern 15p in the chip pattern region 15c, which is set as an invalid region R, is damaged. Therefore, even when the template 10 with the invalid region R is pressed onto the resist on the substrate 20, the fine pattern 15p is not properly transferred to the chip region 25c corresponding to the chip pattern region 15c set as an invalid region R.

[0047] Such partially damaged templates 10 are templates that have become unusable and are subject to replacement due to damage caused by, for example, the imprint process in the manufacturing process of semiconductor devices in the past. In other words, templates 10-2 to 10-p in this embodiment are templates that have been partially damaged in the past and are subject to replacement, and the imprint method in this embodiment is a method that includes reusing the area of ​​templates 10-2 to 10-p excluding the damaged portion.

[0048] Information regarding the setting location of the invalid area R is stored as layout information in the HDD of the control unit 91. The layout information is analyzed by the control unit 91 in order to select the template 10 to be used for imprint processing from among multiple templates 10.

[0049] However, the layout shown in Figure 4 is merely an example and is not limited to it. For example, multiple non-adjacent chip pattern regions 15c may each be set as invalid regions R.

[0050] From this point forward, the template used for imprinting among the multiple templates 10 may be specifically referred to as template 10A.

[0051] (Example of imprint device operation) Figure 5 is a diagram illustrating an example of the operation of the imprint device 1 in the imprint process according to the embodiment.

[0052] As shown in Figure 5(a), a shot area 25SH to be processed is arranged on the substrate 20 placed on the wafer stage 82. A film to be processed 21 is formed on the substrate 20. The film to be processed 21 may be, for example, an insulating film, a conductive film, or a laminate of the same, and may also include an adhesion film. A droplet 110d is dropped onto the shot area 25SH by the droplet dispenser 87 (Figure 3) of the imprint apparatus 1. The droplet 110d is, for example, a photocurable resist, and is dropped onto the film to be processed 21 in a liquid state before curing. The droplet 110d is dispersed throughout the entire area of ​​the shot area 25SH.

[0053] The amount of each droplet 110d, the number of droplets, and the placement of each droplet are defined in the drop recipe. For example, the drop recipe may define the number of droplets 110d and their placement so that the droplets 110d are dropped at equal intervals across the entire shot area 25SH. Alternatively, the drop recipe may define the number of droplets 110d and their placement so that the number of droplets in a predetermined area within the shot area 25SH is selectively increased. As the number of droplets 110d increases, the amount of resist in the predetermined area within the shot area 25SH increases.

[0054] After a droplet 110d is dropped onto the shot area 25SH, the template 10A is positioned opposite the shot area 25SH in the vertical direction. Alignment is performed by the alignment unit 86 (Figure 3), and the template 10A is pressed against the droplet 110d.

[0055] As shown in Figure 5(b), when the template 10A is pressed against the substrate, the multiple droplets 110d are compressed and spread out, forming a resist layer 110s into which the entirety of the multiple droplets 110d is almost integrated. At this time, the template 10A is held above the substrate 20 with a small gap remaining between it and the film to be processed 21. As a result, a portion of the resist layer 110s is gradually filled into the uneven areas of the fine pattern 15p provided on the template 10A by capillary action.

[0056] Next, with the template 10A pressed against the resist layer 110s, light is irradiated from the light source 89 (Figure 3) of the imprint device 1 to cure the resist layer 110s. As a result, the fine pattern 15p of the template 10A is transferred to the resist layer 110s.

[0057] As shown in Figure 5(c), when the template 10A is released, a resist pattern 22p with the fine pattern 15p transferred onto it is formed on the substrate 20.

[0058] Between the workpiece 21 and the bottom surface 221 of the recess 220 of the resist pattern 22p, a resist residue 110r is formed due to the gap between the workpiece 21 and the template 10A. The resist residue 110r is a part of the resist layer 110s. Hereafter, the thickness of this resist residue 110r will be referred to as the residual layer thickness RLT (RLT: Residual Layer Thickness). That is, the residual layer thickness RLT is the thickness of the resist residue 110r at the bottom surface 221 of the recess 220 of the resist pattern 22p.

[0059] Once the formation of the resist pattern 22p is complete in all the shot areas 25SH on the substrate 20 that are to be processed, the substrate 20 is removed from the imprint apparatus 1. After being removed from the imprint apparatus 1, the film to be processed 21 is etched using the resist pattern 22p as a mask.

[0060] From this point forward, the substrate 20 and the processed film 21 formed on the substrate 20 may be referred to simply as "substrate 20".

[0061] Incidentally, during the manufacturing process of a semiconductor device, foreign matter may be placed on the substrate 20 that is to be imprinted. If imprinting is performed on a substrate 20 with foreign matter on it, the template 10A may be damaged. This is because the template 10A and the foreign matter come into contact when the template 10A is pressed against the droplet 110d. The template 10 that comes into contact with the foreign matter deforms by bending up and down with the foreign matter as a fulcrum. As the deformation progresses, the template 10A will be damaged.

[0062] Therefore, the inventors found that damage to the template 10A can be suppressed by increasing the thickness of the resist between the substrate 20 and the template 10A when the template 10A is pressed against it, i.e., the subsequent residual thickness RLT. For example, the residual thickness RLT can be increased by increasing the number of droplets 110d dropped to increase the amount of resist on the substrate 20.

[0063] However, if the residual film thickness RLT is increased, the fine pattern 15p of the template 10A may not be properly transferred to the resist layer 110s, resulting in poor formation of the resist pattern 22p. This is because the filling ability of the resist layer 110s into the uneven areas of the fine pattern 15p deteriorates.

[0064] The packing ability of the resist layer 110s into the uneven areas of the fine pattern 15p can be indicated by the capillary force ΔP of the resist layer 110s. The capillary force ΔP is expressed as ΔP = 2γL × Cosθ / R, where R is half the remaining film thickness RLT, γL is the surface tension of the resist, and θ is the contact angle of the template 10. In other words, the larger the remaining film thickness RLT, the lower the capillary force ΔP becomes. That is, the larger the remaining film thickness RLT, the worse the packing ability of the resist layer 110s into the uneven areas of the fine pattern 15p becomes.

[0065] Furthermore, increasing the number of droplets 110d can increase the overall imprint processing time. This reduces the number of substrates 20 processed per unit time, resulting in a decrease in the production volume of semiconductor devices.

[0066] To solve the above-mentioned problems while suppressing damage to the template 10A, the control unit 91 of the imprint device 1 executes at least one of the first and second control processes. The first and second control processes are performed as part of the imprint process. The first and second control processes will be described below with reference to Figures 6 and 7.

[0067] During the execution of the first and second control processes, the control unit 91 acquires inspection data of the substrate 20. The inspection data is information that associates the particle size, the shot area 25SH where the foreign object is located, the chip area 25c where the foreign object is located, and the coordinates of the foreign object on the substrate 20 with each of the multiple foreign objects. The control unit 91 may acquire the inspection data from the HDD described above, for example, or it may acquire the inspection data from the inspection unit 90 without going through the HDD, for example.

[0068] Based on the inspection data, the control unit 91 determines whether the particle size of foreign matter present in each shot region 25SH exceeds a preset value D0 and a first size D1 (D1 > D0). D0 is, for example, 100 nm, and D1 is, for example, 1 μm.

[0069] (First control process) The control unit 91 executes a first control process if it determines that the particle size of the foreign matter is greater than D0 and less than or equal to D1. The first control process is a process that changes the residual film thickness RLT in the shot region 25SH where the foreign matter is present, according to the particle size of the foreign matter. When executing the first control process, the control unit 91 refers to the correlation data shown in Figure 6. The correlation data in Figure 6 was obtained in advance through experiments, etc.

[0070] Figure 6 shows correlation data between the particle size of foreign matter and the minimum residual thickness (RLT) required to suppress template damage. In Figure 6, the horizontal axis corresponds to the minimum residual thickness (RLT) required to suppress template damage, and the vertical axis corresponds to the particle size of foreign matter.

[0071] Figure 6 shows that, in the range where the particle size of the foreign matter exceeds D0 and is less than or equal to D1, the minimum residual thickness RLT required to suppress damage to the template 10 depends on the particle size of the foreign matter. That is, if the particle size of the foreign matter is small, the minimum residual thickness RLT required to suppress damage to the template 10 can be small, and if the particle size of the foreign matter is large, the minimum residual thickness RLT required to suppress damage to the template 10 will be large.

[0072] Based on such correlation data and the particle size of the foreign matter obtained from the inspection data, the control unit 91 calculates a set value of the remaining film thickness RLT in the shot area 25SH.

[0073] For example, when the particle size of the foreign matter existing in the shot area 25SH obtained from the inspection data is D2 (D0 < D2 ≤ D1), the control unit 91 calculates T2 corresponding to D2 as the set value of the remaining film thickness RLT in the shot area 25SH based on the correlation data in FIG. 6.

[0074] The control unit 91 generates a drop recipe based on the calculated set value of the remaining film thickness RLT. Specifically, for example, the control unit 91 calculates the number of droplets 110d to be dropped for the remaining film thickness RLT to become T2. The control unit 91 defines the number of droplets 110d and the drop position in the drop recipe so that the remaining film thickness RLT in the peripheral area of the foreign matter becomes T2 based on the calculation result of the number of droplets 110d and the coordinates where the foreign matter is present obtained from the inspection data.

[0075] For the area of the shot area 25SH excluding the peripheral area of the foreign matter, the number of droplets 110d and the drop position are defined in the drop recipe so that the remaining film thickness RLT commonly becomes T0 (T0 < T2). T0 is the minimum thickness required to form the resist pattern 22p. Hereinafter, T0 may be referred to as the standard remaining film thickness.

[0076] The control unit 91 controls the droplet dropping device 87 (FIG. 3) and drops the droplets 110d into the shot area 25SH using the generated drop recipe. Thereby, the remaining film thickness RLT in the peripheral area of the foreign matter in the shot area 25SH can be selectively set to T2 (T2 > T0), and the remaining film thickness RLT in the other areas can be set to T0, which is the standard remaining film thickness.

[0077] Thus, according to the first control process, the residual film thickness RLT of a predetermined area of ​​the shot region 25SH is changed according to the particle size of the foreign matter. This prevents the residual film thickness RLT from becoming unnecessarily large, thereby suppressing defects in the formation of the resist pattern 22p and an increase in processing time, while also suppressing damage to the template 10A.

[0078] In the example above, the residual film thickness RLT in the area surrounding the foreign matter within the shot region 25SH was selectively changed, but this is not limited to this. For example, the residual film thickness RLT could be changed in common across the entire shot region 25SH where the foreign matter is present.

[0079] Furthermore, if the particle size of the foreign matter is D0 or less, the first control process described above is not performed. This is because, if the particle size of the foreign matter is D0 or less, and the remaining film thickness RLT is T0, which is the standard remaining film thickness, damage to the template 10 can be suppressed.

[0080] (Second control process) The control unit 91 executes a second control process if it determines that the particle size of the foreign matter exceeds D1, which is the first size. The second control process is to select a template 10A to be used for the imprint process from among multiple templates 10 according to the position of the foreign matter in the shot area 25SH. When executing the second control process, the control unit 91 refers to the layout information of the multiple templates 10 as described in Figure 4.

[0081] The control unit 91 selects a template from among the multiple templates 10 that corresponds to the location of the invalid area R set in each template 10 and the location of the chip area 25c where the foreign object is located, based on the chip area 25c where the foreign object is located, obtained from the inspection data and the layout information of the multiple templates 10 stored in the template storage unit 93.

[0082] Figure 7 shows a shot region 25SH and a corresponding template 10 side by side according to the embodiment. In each of Figures 7(a) to (c), an example of a shot region 25SH containing foreign matter is shown on the left side of the page, and the transfer surface 15s of the template 10 corresponding to the shot region 25SH is shown on the right side of the page.

[0083] As shown in Figure 7(a), we assume an example where foreign matter P1 (particle size of foreign matter P1 > D1) is present in the chip region 25c-2 of the shot region 25SHq. In this case, the control unit 91 selects template 10-2 from templates 10-1 to 10-p, in which an invalid region R is set in the chip pattern region 15c-2 corresponding to the chip region 25c-2, as template 10A to be used for imprint processing.

[0084] For example, as shown in Figure 7(b), consider a case where foreign matter P2 and P3 (particle size of foreign matter P2, particle size of foreign matter P3 > D1) are present in the chip regions 25c-4 and 25c-8 of the shot region 25SHr. In this case, the control unit 91 selects template 10-p as template 10A from among templates 10-1 to 10-p, in which invalid regions R are set in the chip pattern regions 15c-4 and 15c-8, respectively, which correspond to the chip regions 25c-4 and 25c-8.

[0085] As shown in the examples in Figures 7(a) and 7(b), the chip region 25c where the foreign matter is present and the chip pattern region 15c which is set as an invalid region R completely overlap, resulting in a 1:1 correspondence. That is, when the substrate 20 and the template 10 are aligned, the chip pattern region 15c opposite the chip region 25c where the foreign matter is present has an invalid region R set, and the chip region 25c opposite the chip pattern region 15c which is set as an invalid region R has a foreign matter present.

[0086] However, the chip area 25c where foreign matter is present and the chip pattern area 15c which is set as an invalid area R do not necessarily have to have a one-to-one correspondence.

[0087] For example, as shown in Figure 7(c), if foreign matter P4 is present in the chip region 25c-8 of the shot region 25SHs, template 10-p, in which chip pattern regions 15c-4 and 15c-8 are set as invalid region R, may be selected as template 10A. That is, when the substrate 20 and template 10 are aligned, it is sufficient that the chip region 25c containing the foreign matter faces one of the chip pattern regions 15c that are set as invalid region R.

[0088] When the selected template 10A is pressed against the droplet 110d, the chip pattern region 15c, which is set as the invalid region R, and the chip region 25c, which contains foreign matter, face each other vertically. As described above, the fine pattern 15p of the chip pattern region 15c, which is set as the invalid region R, is already partially damaged. Therefore, the fine pattern 15p of the opposing chip pattern region 15c will be damaged again by the foreign matter on the chip region 25c, but this is acceptable. On the other hand, the chip pattern region 15c excluding the invalid region R will not be newly damaged.

[0089] Thus, according to the second control process, a template 10A to be used for the imprint process is selected from multiple templates 10 according to the position of the foreign object. This suppresses further damage to the template 10A.

[0090] Furthermore, generally, if the particle size of the foreign matter is large, imprinting may not be performed on the shot area 25SH where the large foreign matter is present in order to avoid damage to the template 10. According to the second control process, the fine pattern 15p is successfully transferred to the chip area 25c facing the chip pattern area 15c, excluding the invalid area R. As a result, the number of chips cut out in the semiconductor device manufacturing process can be increased compared to the case where imprinting is not performed on the shot area 25SH.

[0091] Figure 8 is a flowchart illustrating the flow of the imprint process performed in the imprint device 1 according to the embodiment. The first and second control processes described above are performed as part of the imprint process.

[0092] In the imprint apparatus 1, the processing order for performing imprint processing on multiple shot regions 25SH on the substrate 20 is predetermined. In this embodiment, for example, the imprint processing is performed sequentially on adjacent shot regions 25SH.

[0093] Prior to the start of the imprint process, the template stage 81 is initially loaded with, for example, template 10-1. Template 10-1 is a template in which no invalid region R is set. When the substrate 20 is placed on the wafer chuck 82b, the imprint process begins.

[0094] The control unit 91 acquires the inspection data output from the inspection unit 90 (S201).

[0095] Based on the inspection data, the control unit 91 determines whether or not there are foreign objects with a particle size greater than D0 within the shot area 25SH to be processed (S202). D0 is, for example, 100 nm.

[0096] If the control unit 91 determines that there are no foreign objects with a particle size greater than D0 in the shot area 25SH (S202: No), it controls the droplet dispenser 87 to drop droplets 110d into the shot area 25SH using a standard drop recipe (S203). The standard drop recipe is defined so that the residual film thickness RLT throughout the entire shot area 25SH is commonly equal to the standard residual film thickness T0.

[0097] On the other hand, if the control unit 91 determines that there is foreign matter with a particle size greater than D0 within the shot area 25SH (S202: Yes), the process proceeds to S207.

[0098] Next, the control unit 91 determines, based on the inspection data, whether or not there are foreign objects with a particle size greater than D1 within the shot area 25SH to be processed (S207). D1 is, for example, 1 μm.

[0099] If the control unit 91 determines that there are no foreign objects with a particle size greater than D1 within the shot area 25SH (S207: No), the process proceeds to S208. In S208 to S210, the first control process is executed.

[0100] As the first control process, the control unit 91 calculates the minimum residual film thickness RLT setting value necessary to suppress template damage based on the particle size of the foreign matter and the correlation data in Figure 6 (S208). Next, the control unit 91 generates a drop recipe based on the calculated residual film thickness RLT setting value (S209). The control unit 91 controls the droplet dispenser 87 to drop droplets 110d into the shot region 25SH using the generated drop recipe (S210). This changes the residual film thickness RLT in the shot region 25SH.

[0101] On the other hand, if the control unit 91 determines that there is foreign matter with a particle size greater than D1 in the shot region 25SH (S207: Yes), the process proceeds to S211. In S211 to S212, the second control process is executed.

[0102] The control unit 91 identifies the location of the chip region 25c where foreign matter with a particle size greater than D1 exists (S211). Based on the location of the chip region 25c where foreign matter with a particle size greater than D1 exists and the layout information of templates 10-2 to 10-p, the control unit 91 selects a template 10 from templates 10-2 to 10-p where the location of the invalid region R set in each template 10 corresponds to the location of the chip region 25c where the foreign matter exists (S212). In other words, when the substrate 20 and the template 10 are aligned, the control unit 91 selects a template 10 where the chip region 25c where the foreign matter exists faces at least one of the chip pattern regions 15c set as the invalid region R. The selected template 10 is transported from the template storage unit 93 and mounted on the template stage 81. The template 10-1 that was mounted in the initial state is returned to the template storage unit 93.

[0103] Next, the control unit 91 determines whether there are foreign objects with a particle size greater than D0 and less than or equal to D1 in the chip regions 25c, excluding the chip regions 25c identified in S211 as having foreign objects with a particle size greater than D1 (S213). That is, the control unit 91 determines whether there are foreign objects with a particle size of D1 or less in the chip regions 25c that do not correspond to the invalid region R of the template 10 selected in step 212.

[0104] If the control unit 91 determines that there are no foreign matter particles with a particle size greater than D0 and less than or equal to D1 (S213: No), the process proceeds to S203.

[0105] On the other hand, if the control unit 91 determines that there is a foreign object with a particle size greater than D0 and less than or equal to D1 (S213: Yes), the process proceeds to S214. In S214 to S216, the first control process described above is executed.

[0106] Specifically, the control unit 91 calculates a set value for the residual film thickness RLT based on the particle size of foreign matter with a particle size greater than D0 and less than or equal to D1, and the correlation data in Figure 6 (S214). The control unit 91 generates a drop recipe that applies the calculated set value for the residual film thickness RLT (S215). The control unit 91 controls the droplet dispenser 87 to drop droplets 110d onto the shot area 25SH using the generated drop recipe (S216). The process then proceeds to S204 and beyond.

[0107] Thus, if the shot region 25SH contains a mixture of foreign matter with a particle size greater than D1 and foreign matter with a particle size less than D1, two control processes, the first and the second, are executed according to the particle size. Specifically, the second control process is applied according to the foreign matter with a particle size greater than D1, and the first control process is applied according to the foreign matter with a particle size less than D1. By making it possible to apply the first and second control processes to a single shot region 25SH in this way, the number of template layouts 10 used in the second control process, that is, the number of templates 10 stored in the template storage unit 93, can be reduced.

[0108] Next, the control unit 91 controls the stage base 88 to press the template 10A onto the droplet 110d (S204). Next, the control unit 91 controls the light source 89 to cure the resist layer 110s (S205). Next, the control unit 91 controls the stage base 88 to release the template 10A from the resist layer 110s (S206). The imprint process is then completed.

[0109] (Overview) The imprint apparatus 1 of this embodiment changes the remaining film thickness RLT based on the particle size of foreign matter present on the substrate 20.

[0110] By setting the residual film thickness RLT according to the particle size of the foreign matter in this way, it is possible to avoid the residual film thickness RLT becoming unnecessarily large. This makes it possible to suppress damage to the template 10A while suppressing defects in the formation of the resist pattern 22p due to insufficient filling of the uneven parts of the template 10A, and the increase in processing time due to an increase in the number of resist drops.

[0111] Furthermore, the imprint apparatus 1 of this embodiment calculates a set value for the residual film thickness RLT based on correlation data that defines the minimum residual film thickness RLT necessary to prevent damage to the template 10A when changing the residual film thickness RLT. This makes it possible to precisely adjust the residual film thickness RLT to the minimum required for the particle size of the foreign material, thereby more effectively suppressing defects in the formation of the resist pattern 22p and increases in processing time.

[0112] Furthermore, the imprint apparatus 1 of the embodiment further comprises a plurality of templates 10 (10-1 to 10-p). Among the plurality of templates 10, some templates 10 (10-2 to 10-p) have invalid regions R in which the formation of fine patterns 15p is impossible, with each template having a different position. When the particle size of the foreign matter exceeds D1, the imprint apparatus 1 selects the template 10A in which the invalid region R corresponds to the position of the foreign matter from among the templates 10A in which the invalid region R is set, as the template 10A to be imprinted. This suppresses further damage to the template 10A.

[0113] According to the imprint apparatus 1 of this embodiment, it is possible to perform imprint processing on shot regions 25SH where foreign matter is present while suppressing damage to the template 10A. As a result, shot regions 25SH with at least a portion of the resist pattern 22p formed are arranged over substantially the entire surface of the substrate 20. Consequently, when etching the film 21 to be processed using the resist pattern 22p as a mask, etching particles generated by the plasma and reaction products between the particles and the film 21 to be processed are uniformly distributed over substantially the entire surface of the substrate 20. This makes it possible to suppress deterioration of etching uniformity.

[0114] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of symbols]

[0115] 1...Imprint device, 10, 10A...Template, 15c...Chip pattern area, 15p...Fine pattern, 15s...Transfer surface, 20...Substrate, 21...Workpiece layer, 22p...Resist pattern, 25SH...Shot area, 25c...Chip area, 87...Droplet dispenser, 90...Inspection unit, 91...Control unit, 93...Template storage unit, 110d...Droplet, 110s...Resist layer, 110r...Resist residual film, 220...Recess, 221...Bottom surface, R...Ineffective area, RLT...Remaining film thickness.

Claims

1. An imprint apparatus that performs imprint processing to form a resin film on a substrate having multiple shot regions and to form a pattern by pressing a template onto the resin film, The system includes a control unit that controls the imprinting process, The control unit, Based on the particle size of foreign matter present on the substrate, the remaining film thickness, which is the thickness of the resin film at the bottom surface of the recess in the pattern, is changed. Imprinting device.

2. Changing the remaining film thickness means The set value for the remaining film thickness is calculated based on the particle size of the foreign matter. Based on the aforementioned settings, a drop recipe is generated. The process involves using the aforementioned drop recipe to form the resin film in the shot region where the foreign matter is present among the plurality of shot regions, The imprint apparatus according to claim 1.

3. Changing the remaining film thickness means This includes calculating the minimum residual film thickness necessary to prevent damage to the template when the template is pressed against the resin film placed on the substrate where the foreign matter is present, based on correlation data determined for each particle size of the foreign matter, The imprint apparatus according to claim 2.

4. The system further comprises multiple templates, including the aforementioned template, Each of the aforementioned templates is: Each of the multiple shot regions has a transfer surface that is pressed against the resin film, In some of the above-mentioned templates, the transfer surface of some templates has invalid areas set in different positions for each template. The control unit, If the particle size of the foreign matter exceeds the first size, Among the templates in which the invalid area is set, the template in which the invalid area corresponds to the position of the foreign object within the shot area is selected as the template for the imprinting process. The imprint apparatus according to claim 1.

5. The transfer surface has, Multiple chip pattern regions capable of forming multiple chip regions are provided within the shot region. The invalid area is, It is set per chip pattern area. The imprint apparatus according to claim 4.

6. An imprint method for forming a predetermined pattern by pressing a template onto a resin film formed on a substrate having multiple shot regions, The process includes changing the remaining film thickness, which is the thickness of the resin film at the bottom surface of the recess in the pattern, based on the particle size of foreign matter present on the substrate. Imprinting method.

7. The system comprises multiple templates, including the aforementioned template, Each of the aforementioned templates is: Each of the multiple shot regions has a transfer surface for forming the pattern, In some of the above-mentioned templates, the transfer surface of some templates has invalid areas set in different positions for each template. A step of determining the position of the foreign matter within the shot region as the particle size of the foreign matter exceeds a first size, A step of selecting from the plurality of templates the template that corresponds to the invalid region and the location of the foreign object, Further including, The imprinting method according to claim 6.

8. A method for manufacturing a semiconductor device, comprising an imprint method for forming a predetermined pattern by pressing a template onto a resin film formed on a semiconductor substrate having multiple shot regions, The process includes changing the remaining film thickness, which is the thickness of the resin film at the bottom surface of the recess in the pattern, based on the particle size of foreign matter present on the semiconductor substrate. The process includes using the pattern formed on the resin film by the imprint method as a mask to process the film to be processed. A method for manufacturing a semiconductor device.

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