Template, processed component and alignment method

Abstract

The alignment marks include first marks arranged at a first pitch along a first direction, and second marks arranged at a second pitch along the first direction. At least one of the first marks includes a first region and a third region. At least one of the second marks includes a second region and a third region. The first region has a first pattern arranged in lines and spaces along the first direction. The second region has a second pattern arranged in lines and spaces along a second direction perpendicular to the first direction.

Description

[0001] Related applications

[0002] This application is based on and claims the benefit of priority arising from the prior Japanese patent application No. 2021-048653 filed on March 23, 2021, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] Embodiments of the present invention relate to a template, a workpiece, and an alignment method. Background Art

[0004] The semiconductor device manufacturing process utilizes an imprint method to form fine patterns on a workpiece. This method involves an alignment process to align the position of a patterned template with the workpiece. This alignment process uses alignment marks placed on the template and the workpiece. With the miniaturization of semiconductor devices and the resulting reduction in pattern size, there is a need to reduce the area occupied by alignment marks. Summary of the Invention

[0005] Embodiments of the present invention provide a template, a workpiece, and an alignment method that can achieve high-precision alignment using alignment marks that are smaller than those in the related art.

[0006] According to one embodiment of the present invention, a template having alignment marks is provided. The alignment marks include first marks arranged at a first pitch along a first direction, and second marks arranged at a second pitch along the first direction. At least one of the first marks includes a first region and a third region. At least one of the second marks includes a second region and a third region. The first region has a first pattern arranged in a line-and-space pattern along the first direction. The second region has a second pattern arranged in a line-and-space pattern along a second direction perpendicular to the first direction.

[0007] According to the above configuration, it is possible to provide a template, a workpiece, and an alignment method that can achieve high-precision alignment using alignment marks that are smaller than those in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a bottom view showing an example of the structure of the template according to the first embodiment.

[0009] Figure 2 It is a bottom view showing an example of the configuration of the alignment mark of the template according to the first embodiment.

[0010] Figure 3It is a III-III cross-sectional view showing an example of the configuration of the alignment mark of the template according to the first embodiment.

[0011] Figure 4 This is a partially enlarged bottom view showing an example of the configuration of the first region according to the first embodiment.

[0012] Figure 5 This is a partially enlarged bottom view showing an example of the configuration of the second region according to the first embodiment.

[0013] Figure 6 It is a partially enlarged cross-sectional view showing the configuration of the third region according to the first example of the first embodiment.

[0014] Figure 7 It is a partially enlarged cross-sectional view showing the configuration of the third region according to the second example of the first embodiment.

[0015] Figure 8 This is a diagram for explaining an example of the relationship among the first region, the second region, and the third region in the alignment mark of the template according to the first embodiment.

[0016] Figure 9 This is a top view showing an example of the structure of the wafer according to the first embodiment.

[0017] Figure 10 It is a top view showing an example of the configuration of the alignment mark of the wafer according to the first embodiment.

[0018] Figure 11 XI-XI is a cross-sectional view showing an example of the configuration of the alignment mark of the wafer according to the first embodiment.

[0019] Figure 12 This is a diagram for explaining an example of the relationship among the first region, the second region, and the third region in the alignment mark of the wafer according to the first embodiment.

[0020] Figure 13 This is a flowchart showing an example of the alignment method according to the first embodiment.

[0021] Figure 14 This is a side cross-sectional view showing an example of a state in which a wafer and a template are located at standard positions in the alignment method according to the first embodiment.

[0022] Figure 15 This is a side cross-sectional view showing an example of a region reflecting X-polarized light when the wafer and the template are located in the standard positions in the first embodiment.

[0023] Figure 16This is a diagram showing an example of the first reference moiré fringe according to the first embodiment.

[0024] Figure 17 This is a side cross-sectional view showing an example of a region reflecting Y-polarized light when the wafer and the template are located at the standard positions in the first embodiment.

[0025] Figure 18 This is a diagram showing an example of the second reference moiré fringe according to the first embodiment.

[0026] Figure 19 This is a side cross-sectional view showing an example of a region reflecting X-polarized light when the wafer and the template are located in non-standard positions in the first embodiment.

[0027] Figure 20 This is a diagram showing an example of comparison between first moiré fringes and first reference moiré fringes that appear when the wafer and the template are positioned at non-standard positions and irradiated with X-polarized light in the first embodiment.

[0028] Figure 21 This is a side cross-sectional view showing an example of a region reflecting Y-polarized light when the wafer and the template are located in non-standard positions in the first embodiment.

[0029] Figure 22 This is a diagram showing an example of comparison between the second moiré fringe that appears when the wafer and the template are located at non-standard positions and irradiated with Y-polarized light in the first embodiment and the second reference moiré fringe.

[0030] Figure 23 This is a diagram showing an example of the configuration of a semiconductor manufacturing apparatus according to the first embodiment.

[0031] Figure 24 It is a diagram schematically showing the configuration of an alignment observation section according to a first example of the first embodiment.

[0032] Figure 25 It is a diagram schematically showing the configuration of an alignment observation section according to a second example of the first embodiment.

[0033] Figure 26 It is a diagram schematically showing the configuration of an alignment observation unit according to a third example of the first embodiment.

[0034] Figure 27 It is a side cross-sectional view showing an example of a semiconductor manufacturing process according to the second embodiment.

[0035] Figure 28 It is a top view showing an example of the structure of a wafer according to the second embodiment.

[0036] Figure 29 It is a top view showing an example of the configuration of an alignment mark according to the second embodiment.

[0037] Figure 30 This is a diagram showing an example of the configuration of an alignment mark according to the second embodiment. DETAILED DESCRIPTION

[0038] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the present invention is not limited by the embodiments. In addition, the constituent elements in the embodiments include elements that are easily conceivable to those skilled in the art or substantially the same elements.

[0039] [First Embodiment] A technique related to alignment between a template and a workpiece (eg, a wafer) in an imprint method in which a predetermined pattern is formed on the workpiece using a template will be described below.

[0040] <Template structure> Refer to Figures 1 to 8 , explaining the structure of the template 1 used in the imprint method. In the figure, the X axis corresponds to the left-right direction in the horizontal plane, the Y axis corresponds to the front-back direction in the horizontal plane, and the Z axis corresponds to the vertical (up-down) direction perpendicular to the horizontal plane.

[0041] Figure 1 This is a bottom view showing an example of the structure of template 1 according to the first embodiment. Template 1 is a plate-shaped member made of a transparent material that transmits visible light and ultraviolet light, for example, a material primarily composed of quartz. The template 1 illustrated here is rectangular, for example, a square with a side length of approximately 150 mm.

[0042] A platform-shaped mesa portion 10 protruding downward is formed in the center of the lower surface of the template 1. The mesa portion 10 is formed with a device pattern area 11 and an alignment area 12. Figure 1 The table portion 10 is shown as a circular table portion when viewed from below (in a plan view), but the table portion 10 may also be rectangular when viewed from below. The device pattern region 11 is formed with a pattern (concave or convex portion) to be impressed on the workpiece.

[0043] Alignment marks used in alignment processing for aligning the template 1 and the workpiece are formed in the alignment region 12. Alternatively, the alignment region 12 may be formed in the device pattern region 11.

[0044] Figure 2 It is a bottom view showing an example of the configuration of the alignment mark 15 of the template 1 according to the first embodiment. Figure 3 It is a III-III cross-sectional view showing an example of the configuration of the alignment mark 15 of the template 1 according to the first embodiment.

[0045] Alignment mark 15 (first alignment mark) includes a plurality of reflective portions 16A, 16B, and 16C. Reflective portions 16A, 16B, and 16C are arranged along the X-axis direction (first direction). Reflective portions 16A, 16B, and 16C are formed on the bottom surfaces of the plurality of recesses 20 formed in alignment region 12.

[0046] The reflective portion 16A includes a first region 21, a second region 22, and a third region 23. The first region 21 is a region in which a reflective film that reflects light (e.g., visible light) is arranged in a line and space (hereinafter referred to as L / S) pattern along the Y-axis direction (the second direction). The second region 22 is a region in which a reflective film is arranged in an L / S pattern along the X-axis direction. The third region 23 is a region in which a reflective film is arranged in a full-surface or lattice pattern. The first region 21 is a region that transmits X-polarized light (first polarized light) whose electric field vibrates along the XZ plane (the first plane) at a higher transmittance than Y-polarized light (second polarized light) whose electric field vibrates along the YZ plane (the second plane orthogonal to the first plane), and reflects Y-polarized light at a higher reflectance than X-polarized light. The second region 22 is a region that transmits Y-polarized light at a higher transmittance than X-polarized light, and reflects X-polarized light at a higher reflectance than Y-polarized light. The third region 23 is a region that reflects both X-polarized light and Y-polarized light. The X-polarized light may be, for example, TM (Transverse Magnetic) polarized light, and the Y-polarized light may be, for example, TE (Transverse Electric) polarized light.

[0047] In addition to the above-mentioned reflective portion 16A, the alignment mark 15 also includes a reflective portion 16B composed of a first region 21 and a second region 22, and a reflective portion 16C composed of a third region 23. Hereinafter, when it is not necessary to distinguish between the reflective portions 16A, 16B, and 16C, they may be referred to as a reflective portion 16.

[0048] also, Figure 2 The configuration of the alignment mark 15 when the template 1 is viewed from the bottom surface side is illustrated. However, since the template 1 is made of a transparent material, the configuration of the alignment mark 15 when the template 1 is viewed from the top surface side is also different. Figure 2 In addition, the following description Figures 4 to 8 Same.

[0049] Figure 4This is a partially enlarged lower surface view showing an example of the structure of the first region 21 involved in the first embodiment. The first region 21 is formed with a reflective film 25 arranged in an L / S pattern along the Y axis (the second direction). The L / S pitch Ps of the reflective film 25 is preferably approximately 100 nm or less. For example, if the pitch Ps is 100 nm or less, the optical properties of the first region 21 (properties of transmitting X-polarized light and reflecting Y-polarized light) and the optical properties of the second region 22 (properties of transmitting Y-polarized light and reflecting X-polarized light) can be well obtained when the wavelength of the inspection light (X-polarized light or Y-polarized light) used in the alignment process is approximately 300 nm to 800 nm. The reflective film 25 is a film (layer) capable of reflecting visible light (light with a wavelength of, for example, 300 nm to 800 nm) and contains a reflective material such as chromium as a main component. With this structure, a first region 21 that transmits X-polarized light and reflects Y-polarized light can be formed.

[0050] Figure 5 This is a partially enlarged bottom view showing an example of the configuration of the second region 22 according to the first embodiment. The second region 22 is formed with a reflective film 25 arranged in an L / S pattern along the X-axis (first direction). The pitch Ps of the L / S arrangement of the reflective film 25 is preferably the same as the pitch Ps in the first region 21. This configuration enables the formation of a second region 22 that transmits Y-polarized light and reflects X-polarized light.

[0051] Figure 6 It is a partially enlarged cross-sectional view showing the structure of the third region 23 according to the first example of the first embodiment.

[0052] The third region 23 according to this example is formed with a solid-surface reflective film 25. With this configuration, the third region 23 that reflects both X-polarized light and Y-polarized light can be formed.

[0053] Figure 7 It is a partially enlarged cross-sectional view showing the structure of the third region 23 according to the second example of the first embodiment.

[0054] The third region 23 according to this example is formed with a lattice-shaped reflective film 25 along the X-axis and the Y-axis. With this configuration, the third region 23 that reflects both X-polarized light and Y-polarized light can be formed.

[0055] The configuration of the third region 23 is not limited to the above, and any configuration is sufficient as long as it can reflect X-polarized light and Y-polarized light at a predetermined reflectivity. For example, the third region 23 may be formed with a lattice-shaped reflective film 25 tilted at 45 degrees relative to the X-axis and the Y-axis.

[0056] Figure 81 is a diagram for explaining an example of the relationship between the first region 21, the second region 22, and the third region 23 in the alignment mark 15 of the template 1 according to the first embodiment. Figure 8 , a virtual first region 21' partially corresponding to the first region 21 and a virtual second region 22' partially corresponding to the second region 22 are illustrated. Multiple virtual first regions 21' are arranged along the X-axis at a first pitch P1, and multiple virtual second regions 22' are arranged along the X-axis at a second pitch P2, with the relationship P1 ≠ P2 (in this embodiment, P1 < P2) being satisfied. The first pitch P1 and the second pitch P2 are preferably approximately 2000 nm or less.

[0057] like Figure 8 As shown, the position where the third region 23 is formed corresponds to the region where the virtual first regions 21' and the virtual second regions 22' overlap when the plurality of virtual first regions 21' and the plurality of virtual second regions 22' are overlapped with the center of their arrangement direction. Figure 2 The alignment mark 15 of the illustrated embodiment includes a first mark including a first region 21 and a third region 23 , and a second mark including a second region 22 and a third region 23 .

[0058] According to the alignment mark 15 having the above-described structure, X-polarized light irradiated onto the alignment mark 15 is reflected by the region formed by both or one of the first region 21 and the third region 23. Furthermore, Y-polarized light irradiated onto the alignment mark 15 is reflected by the region formed by both or one of the second region 22 and the third region 23.

[0059] <Constitution of the workpiece> See below Figures 9 to 12 , the structure of a wafer 51 as an example of a workpiece will be described.

[0060] Figure 9 This is a top view showing an example of the structure of a wafer 51 according to the first embodiment. Wafer 51 is a component processed by imprinting. Its specific structure is not particularly limited. For example, it may include a substrate made of silicon, a base pattern formed on the substrate, and a processed layer formed on the base pattern. The processed layer may be, for example, an insulating film, a metal film (conductive film), a semiconductor film, or the like.

[0061] like Figure 9 As shown, a device region 61 and a plurality of alignment regions 62 are formed on the upper surface (processed surface) of the wafer 51 according to this embodiment.

[0062] The device region 61 is an area where a predetermined device structure (e.g., a three-dimensional NAND) is formed. Predetermined layers (such as a protective layer and a resist layer) are formed in the device region 61, and then imprinting is performed using the template 1. After the predetermined device structure is formed in each of the plurality of device regions 61, each device region 61 is singulated and separated into individual pieces, thereby manufacturing a semiconductor device.

[0063] The alignment region 62 is formed with an alignment mark used in an alignment process for aligning the wafer 51 and the template 1. Alternatively, the alignment region 62 may be formed within the device region 61.

[0064] Figure 10 It is a top view showing an example of the configuration of the alignment mark 65 of the wafer 51 according to the first embodiment. Figure 11 XI-XI is a cross-sectional view showing an example of the configuration of the alignment mark 65 of the wafer 51 according to the first embodiment.

[0065] The alignment mark 65 (second alignment mark) includes a plurality of reflection portions 66A, 66B, and 66C. The plurality of reflection portions 66A, 66B, and 66C are each formed on the bottom surface of each of the plurality of recesses 60 formed in the alignment region 62 .

[0066] The reflective portion 66A includes a first region 21, a second region 22, and a third region 23. The first region 21, the second region 22, and the third region 23 in the alignment mark 65 have the same structure as the first region 21, the second region 22, and the third region 23 in the template 1 described above. That is, the first region 21 of the alignment mark 65 is a region where the reflective film 25 that reflects light is arranged in an L / S pattern along the Y-axis direction (the second direction). The second region 22 of the alignment mark 65 is a region where the reflective film 25 is arranged in an L / S pattern along the X-axis direction. The third region 23 of the alignment mark 65 is a region where the reflective film 25 is arranged in a full-surface or grid pattern. In addition, the first region 21 of the alignment mark 65 transmits X-polarized light (first polarized light) at a higher transmittance than Y-polarized light, and reflects Y-polarized light at a higher reflectance than X-polarized light. The second region 22 of the alignment mark 65 transmits Y polarized light at a higher transmittance than X polarized light and reflects X polarized light at a higher reflectance than Y polarized light. The third region 23 of the alignment mark 65 reflects both X polarized light and Y polarized light.

[0067] In addition to the reflective portion 66A, the alignment mark 65 according to this embodiment also includes a reflective portion 66B formed by the first region 21 and the second region 22, and a reflective portion 66C formed by the third region 23. Hereinafter, when it is not necessary to distinguish between the reflective portions 66A, 66B, and 66C, they may be referred to as the reflective portion 66.

[0068] Figure 12 1 is a diagram for explaining an example of the relationship between the first region 21, the second region 22, and the third region 23 in the alignment mark 65 of the wafer 51 according to the first embodiment. Figure 12 , a portion of the imaginary first region 21' corresponding to the first region 21 and a portion of the imaginary second region 22' corresponding to the second region 22 are illustrated. A plurality of imaginary first regions 21' are arranged at intervals of a second pitch P2 along the X-axis, and a plurality of imaginary second regions 22' are arranged at intervals of a first pitch P1 along the X-axis. That is, the imaginary first regions 21' in the wafer 51 are arranged at the same second pitch P2 as the imaginary second regions 22' in the template 1, and the imaginary second regions 22' in the wafer 51 are arranged at the same first pitch P1 as the imaginary first regions 21' in the template 1.

[0069] like Figure 12 As shown, the position where the third region 23 is formed corresponds to the region where the virtual first regions 21' and the virtual second regions 22' overlap when the plurality of virtual first regions 21' and the plurality of virtual second regions 22' are overlapped with the center of their arrangement direction. Figure 10 The alignment mark 65 of the illustrated embodiment includes a first mark including the first region 21 and the third region 23 , and a second mark including the second region 22 and the third region 23 .

[0070] According to the alignment mark 65 having the above-described structure, similarly to the alignment mark 15 of the template 1, the X-polarized light irradiated onto the alignment mark 65 is reflected by the region formed by both or one of the first region 21 and the third region 23. Furthermore, the Y-polarized light irradiated onto the alignment mark 65 is reflected by the region formed by both or one of the second region 22 and the third region 23.

[0071] <Alignment Method> Next, an alignment method for aligning the template 1 and the wafer 51 using the alignment marks 15 and 65 will be described.

[0072] Figure 13 This is a flowchart illustrating an example of an alignment method according to the first embodiment. After wafer 51 and template 1 are placed in a predetermined arrangement ( S101 ), a rough alignment process is performed to position wafer 51 and template 1 in approximately appropriate positions ( S102 ). The specific method for the rough alignment process is not particularly limited and can be implemented using known techniques as appropriate. For example, the rough alignment process can be performed using alignment marks 15 and 65 , or using specially designated appropriate marks.

[0073] Then, the moiré fringes that appear when X-polarized light (e.g., TM polarized light) is irradiated from the upper surface of the template 1 toward the alignment mark 15 are photographed, and first moiré fringe information related to the moiré fringes corresponding to the X-polarized light is acquired (S103). Then, the moiré fringes that appear when Y-polarized light (e.g., TE polarized light) is irradiated from the upper surface of the template 1 toward the alignment mark 15 are photographed, and second moiré fringe information related to the moiré fringes corresponding to the Y-polarized light is acquired (S104).

[0074] Then, offset information indicating positional offset between the wafer 51 and the template 1 is generated based on the first and second moiré fringe information ( S105 ), and the relative position of the wafer 51 and the template 1 is adjusted based on the offset information ( S106 ).

[0075] Figure 14 1 is a side cross-sectional view showing an example of a state in which the wafer 51 and the template 1 are located at a standard position in the alignment method according to the first embodiment. Figure 14 , and the following Figure 15 、 Figure 17 、 Figure 19 as well as Figure 21 In the example, the recess 20 of the template 1 is omitted ( Figure 3 ) and the concave portion 60 of the wafer 51 ( Figure 11 ) records.

[0076] like Figure 14 As shown, when wafer 51 and template 1 are positioned in standard, properly defined positions, the reflective portions 66 of alignment mark 65 on wafer 51 and the reflective portions 16 of alignment mark 15 on template 1 are aligned vertically (in the Z-axis direction). At this point, first region 21 of alignment mark 65 on wafer 51 and second region 22 of alignment mark 15 on template 1 are aligned, and third region 23 of alignment mark 65 on wafer 51 and third region 23 of alignment mark 15 on template 1 are aligned. In this state, if inspection light is applied from the top surface of template 1, moiré fringes appear due to the reflected light from reflective portions 16 and 66. The light and dark pattern of these moiré fringes changes in accordance with the vertical overlap of reflective portions 16 and 66.

[0077] Figure 15 1 is a side cross-sectional view showing an example of a region reflecting X-polarized light 70X when the wafer 51 and the template 1 are located at the standard position in the first embodiment. Figure 15As shown, X-polarized light 70X irradiated from the upper surface of template 1 is reflected by first region 21 and third region 23 and transmitted through second region 22. In other words, the region where X-polarized light 70X is reflected is the combined region of first region 21 and third region 23. By observing the reflected light of X-polarized light 70X from the upper surface of template 1, first reference moiré fringes are observed, which appear when wafer 51 and template 1 are positioned at the standard position and irradiated with X-polarized light 70X.

[0078] Figure 16 This is a diagram showing an example of the first reference moiré fringe 71 according to the first embodiment. Figure 16 exemplarily shows the first reference moiré fringe 71 viewed from the upper surface of the template 1 . Figure 16 The area depicted with a grid in the figure corresponds to the reflection area of the first area 21 and the third area 23 when viewed from above. The light and dark pattern of the first reference moiré fringe 71 is formed so that the area corresponding to the reflection area of the first area 21 and the third area 23 is brighter, and the other areas (such as the area corresponding to the second area 22) are darker.

[0079] Figure 17 1 is a side cross-sectional view showing an example of a region reflecting Y polarized light 70Y when the wafer 51 and the template 1 are located at the standard position in the first embodiment. Figure 17 As shown, Y-polarized light 70Y irradiated from the top surface of template 1 is reflected by second region 22 and third region 23 and transmitted through first region 21. That is, the region where Y-polarized light 70Y is reflected is the combined region of second region 22 and third region 23. By observing the reflected light of Y-polarized light 70Y from the top surface of template 1, second reference moiré fringes are observed, which appear when wafer 51 and template 1 are positioned at the standard position and irradiated with Y-polarized light 70Y.

[0080] Figure 18 This is a diagram showing an example of the second reference moiré fringe 72 according to the first embodiment. Figure 18 The second reference moiré fringe 72 observed from the upper surface of the template 1 is illustrated. Figure 18 The area depicted with the inclined grid corresponds to the reflection area of the second area 22 and the third area 23 when viewed from above. The light and dark pattern of the second reference moiré fringe 72 is formed so that the area corresponding to the reflection area of the second area 22 and the third area 23 is brighter, and the other areas (such as the area corresponding to the first area 21) are darker.

[0081] Figure 19 : is a side cross-sectional view showing an example of a region reflecting X-polarized light 70X when the wafer 51 and the template 1 are located in non-standard positions in the first embodiment. Figure 19, a state in which the wafer 51 is displaced from the standard position to the right in the figure along the X-axis direction is illustrated.

[0082] Figure 20 This figure shows an example of comparison between first moiré fringes 71 ′ and first reference moiré fringes 71 that appear when the wafer 51 and the template 1 are located at non-standard positions and irradiated with X-polarized light 70X in the first embodiment. Figure 20 exemplified in Figure 19 The illustrated state is a first moiré fringe 71' that appears when the wafer 51 is shifted from the standard position to the right in the figure along the X-axis and irradiated with X-polarized light 70X. Figure 20 As shown, the displacement direction of the light and dark pattern of the first moiré fringe 71 ′ (moiré fringe displacement direction) is opposite to the shift direction of the wafer 51 .

[0083] Figure 21 : is a side cross-sectional view showing an example of a region reflecting Y polarized light 70Y when the wafer 51 and the template 1 are located in non-standard positions in the first embodiment. Figure 21 , a state in which the wafer 51 is displaced from the standard position to the right in the figure along the X-axis direction is illustrated.

[0084] Figure 22 This figure shows an example of comparison between the second moiré fringe 72 ′ and the second reference moiré fringe 72 that appear when the wafer 51 and the template 1 are located at non-standard positions and irradiated with Y-polarized light 70Y in the first embodiment. Figure 22 Illustrated Figure 21 The illustrated state is a second moiré fringe 72' that appears when the wafer 51 is shifted from the standard position to the right in the figure along the X-axis and irradiated with Y-polarized light 70Y. Figure 22 As shown, the displacement direction of the light and dark pattern of the second moiré fringe 72 ′ (moiré fringe displacement direction) coincides with the shift direction of the wafer 51 .

[0085] As described above, even if the relative position between wafer 51 and template 1 is offset in the same direction, the moiré fringe displacement directions of first moiré fringes 71' due to X-polarized light 70X and second moiré fringes 72' due to Y-polarized light 70Y are opposite to each other. Thus, by analyzing the two types of moiré fringes 71' and 72' generated by switching between irradiation with X-polarized light 70X and Y-polarized light 70Y, the accuracy of positional offset detection can be improved. Furthermore, by overlapping first region 21 and second region 22 as described above and arranging third region 23 in the overlapping region, the area of alignment marks 15 and 65 can be reduced. This allows for highly accurate alignment using alignment marks 15 and 65 that are smaller than in conventional techniques.

[0086] <Semiconductor Manufacturing Apparatus> Hereinafter, a semiconductor manufacturing apparatus for manufacturing semiconductor devices by performing an imprint process using the above-described template 1 , wafer 51 (processed member), and alignment method will be described.

[0087] Figure 23 1 is a diagram showing an example of the configuration of a semiconductor manufacturing apparatus 110 according to the first embodiment. The semiconductor manufacturing apparatus 110 includes a substrate stage 111. The substrate stage 111 is provided with a chuck 112. The chuck 112 holds the wafer 51. The chuck 112 holds the wafer 51 by an appropriate method such as vacuum suction.

[0088] The substrate stage 111 is movably mounted on a stage plate 113. The substrate stage 111 is movable along the upper surface 113a (XY plane) of the stage plate 113 and along the Z-axis, which is perpendicular to the XY plane. Furthermore, the substrate stage 111 is preferably rotatable about the X-axis, the Y-axis, and the Z-axis.

[0089] The substrate stage 111 is provided with a reference mark stage 114. Reference marks (not shown) are provided on the reference mark stage 114, serving as reference positions for the semiconductor manufacturing apparatus 110. The reference marks may be, for example, a checkerboard-shaped diffraction grating. The reference marks are used for calibration of the alignment observation unit 130, pre-positioning of the template 1 (rough alignment processing), and the like. The reference marks may be the origin on the substrate stage 111. In this case, the X and Y coordinates of the wafer 51 placed on the substrate stage 111 can be processed as coordinates with the position of the reference mark stage 114 as the origin.

[0090] The semiconductor manufacturing apparatus 110 includes a template stage 121 . The template stage 121 fixes the template 1 . The template stage 121 holds the peripheral edge of the template 1 by an appropriate method such as vacuum suction. The template stage 121 is attached to a base 122 .

[0091] The base 122 is provided with a correction mechanism 123 and a pressurizing unit 124. The correction mechanism 123, for example, receives instructions from the controller 150 to fine-tune the position (posture) of the template 1. The pressurizing unit 124 applies stress to the side surfaces of the template 1 to correct any skew. The pressurizing unit 124 applies pressure to the center of the template 1 from all four sides. This allows the size of the transferred pattern to be corrected (magnification correction). The pressurizing unit 124, for example, receives instructions from the controller 150 to apply a predetermined stress to the template 1.

[0092] The base 122 is mounted on an alignment stage 125. The alignment stage 125 moves the base 122 in the X-axis direction or the Y-axis direction to align the template 1 and the wafer 51. The alignment stage 125 also rotates the base 122 along the XY plane.

[0093] The alignment observation unit 130 is a device for observing moiré fringes that appear when alignment inspection light is irradiated onto the alignment marks 15 provided on the template 1 and the alignment marks 65 provided on the wafer 51. The alignment observation unit 130 includes a mechanism for irradiating the inspection light, a mechanism for receiving light reflected from the template 1, and a mechanism for photoelectrically converting the received light. Based on information related to the moiré fringes observed (photographed) by the alignment observation unit 130, the relative position between the wafer 51 and the template 1 is adjusted to a standard position.

[0094] Semiconductor manufacturing apparatus 110 includes a processing light source 141 and a coating unit 142. The processing light source 141 irradiates electromagnetic waves in the ultraviolet region, for example. The processing light source 141 receives instructions from a controller 150 to start and stop irradiating the template 1. The coating unit 142 is a mechanism for coating the wafer 51 with a resist layer. The coating unit 142 can be, for example, a spray head having a nozzle. The coating unit 142 receives instructions from the controller 150 to drip the resist layer onto a predetermined location on the wafer 51.

[0095] The semiconductor manufacturing apparatus 110 includes a controller 150. The controller 150 controls the entire semiconductor manufacturing apparatus 110. The controller 150 executes the aforementioned processes according to a program that describes the respective processes, including control of the alignment observation unit 130, alignment processing for aligning the wafer 51 with the template 1, control of the coating unit 142, and control of the processing light source 141. During the alignment process, the controller 150 controls the substrate stage 111, base unit 122, alignment stage 125, and the like based on information related to moiré fringes acquired by the alignment observation unit 130, so that the position between the wafer 51 and the template 1 reaches the standard position.

[0096] <Configuration Example of Alignment Observation Unit> Figures 24 to 26 , a configuration example of the alignment observation unit 130 will be described.

[0097] Figure 24 1 is a diagram schematically showing the configuration of an alignment observation unit 130A according to a first example of the first embodiment. The alignment observation unit 130A according to this example includes an X-polarized light source 501 , a Y-polarized light source 502 , a transflective reflector 503 , a first reflector 504 , a second reflector 505 , and a light receiving unit 511 .

[0098] X-polarized light source 501 emits X-polarized light 70X (e.g., TM polarized light). Y-polarized light source 502 emits Y-polarized light 70Y (e.g., TE polarized light). Transflector 503 transmits Y-polarized light 70Y and reflects X-polarized light 70X. First reflector 504 and second reflector 505 reflect X-polarized light 70X and Y-polarized light 70Y. Light receiving unit 511 performs photoelectric conversion on the incident light to generate information related to the moiré fringes appearing on template 1.

[0099] Y-polarized light 70Y emitted from Y-polarized light source 502 transmits through transflective plate 503 and travels to first reflector 504. X-polarized light 70X emitted from X-polarized light source 501 is reflected by transflective plate 503 and travels to first reflector 504. X-polarized light 70X or Y-polarized light 70Y emitted from transflective plate 503 is reflected by first reflector 504 and irradiates the upper surface of template 1. Light reflected from template 1 (X-polarized light 70X or Y-polarized light 70Y) is reflected by second reflector 505 and received by light receiving unit 511. Information on moiré fringes generated by light receiving unit 511 is output to a control mechanism such as controller 150.

[0100] Figure 25 This figure schematically shows the configuration of the alignment observation unit 130B according to the second example of the first embodiment. The alignment observation unit 130B according to this example includes a light source 601 , a first reflector 602 , a second reflector 603 , a polarizing filter 604 , and a light receiving unit 511 .

[0101] Light source 601 irradiates inspection light 70 in the visible light range. First reflector 602 reflects inspection light 70. Second reflector 603 reflects light reflected from template 1. Polarizing filter 604 includes X-polarizing portion 604A and Y-polarizing portion 604B. X-polarizing portion 604A polarizes incident light into X-polarized light 70X. Y-polarizing portion 604B polarizes incident light into Y-polarized light 70Y. Polarizing filter 604 is configured so that, by displacement via a predetermined drive mechanism, it switches which of X-polarizing portion 604A and Y-polarizing portion 604B is positioned on the optical path. Light receiving unit 511 performs photoelectric conversion on incident light to generate information related to the moiré fringes appearing on template 1.

[0102] Inspection light 70 emitted from light source 601 is reflected by first reflector 602 and directed toward the upper surface of template 1. Reflected light from template 1 is reflected by second reflector 603, passes through either X-polarized portion 604A or Y-polarized portion 604B of polarizing filter 604, and is polarized into either X-polarized light 70A or Y-polarized light 70Y. X-polarized light 70X or Y-polarized light 70Y from polarizing filter 604 is received by light receiving unit 511. Information on the moiré fringes generated by light receiving unit 511 is output to a control mechanism such as controller 150.

[0103] Figure 26 This figure schematically shows the configuration of an alignment observation unit 130C according to the third example of the first embodiment. The alignment observation unit 130C according to this example includes a light source 601, a first reflector 602, a second reflector 603, a polarization beam splitter 701, an X-polarized light receiving unit 702, and a Y-polarized light receiving unit 703.

[0104] Light source 601 irradiates inspection light 70 in the visible light range. First reflector 602 reflects inspection light 70. Second reflector 603 reflects light reflected from template 1. Polarization beam splitter 701 splits the light reflected from template 1 into X-polarized light 70X and Y-polarized light 70Y. X-polarized light receiver 702 performs photoelectric conversion on X-polarized light 70X, generating information related to the moiré fringes appearing on template 1. Y-polarized light receiver 703 performs photoelectric conversion on Y-polarized light 70Y, generating information related to the moiré fringes appearing on template 1.

[0105] Inspection light 70 emitted from light source 601 is reflected by first reflector 602 and directed toward the upper surface of template 1. Reflected light from template 1 is reflected by second reflector 603 and split by polarization beam splitter 701 into X-polarized light 70X and Y-polarized light 70Y. X-polarized light 70X is received by X-polarized light receiving unit 702, and Y-polarized light 70Y is received by Y-polarized light receiving unit 703. Information related to the moiré fringes generated by X-polarized light receiving unit 702 and Y-polarized light receiving unit 703 is output to a control mechanism such as controller 150.

[0106] In the above configuration, by switching between irradiating the alignment marks 15 and 65 with X-polarized light 70X and Y-polarized light 70Y, information related to two types of moiré fringes (moiré fringes corresponding to X-polarized light and moiré fringes corresponding to Y-polarized light) can be acquired. Furthermore, by overlapping the first and second regions 21 and 22 as described above, and arranging the third region 23 in the overlapping region between the first and second regions 21 and 22, the area of the alignment marks 15 and 65 can be reduced. This allows for highly accurate alignment using alignment marks 15 and 65 that are smaller than in conventional techniques.

[0107] In addition, while the above description illustrates an example in which the first region 21 and the second region 22 are formed in an L / S pattern, the configuration of the first region 21 and the second region 22 is not limited thereto. For example, the first region 21 and the second region 22 may be formed in a checkerboard pattern. Alternatively, the first region 21 and the second region 22 of one of the template 1 and the wafer 51 may be formed in an L / S pattern, while the first region 21 and the second region 22 of the other of the template 1 and the wafer 51 may be formed in a checkerboard pattern. Alternatively, the first region 21 and the second region 22 of both the template 1 and the wafer 51 may be formed in a checkerboard pattern.

[0108] [Second Embodiment] A technique related to alignment for adjusting the position of a workpiece (eg, a wafer) when a plurality of steps are performed on a single workpiece will be described below.

[0109] Semiconductor Manufacturing Process Figure 27 This is a side cross-sectional view showing an example of a semiconductor manufacturing process according to the second embodiment. The semiconductor manufacturing process illustrated here includes a first step (1) of forming a first film 811 on a wafer 801, which is an example of a workpiece, and a second step (2) of forming a second film 812 on the first film 812. Before the first step (1) and before the second step (2), an alignment process is performed to position the wafer 801 at a predetermined standard position.

[0110] <Composition of the workpiece> Figure 28 1 is a top view showing an example of the structure of the wafer 801 according to the second embodiment. Figure 28 As shown, a device region 802 and an alignment region 805 are formed on the upper surface (processed surface) of a wafer 801 according to this embodiment.

[0111] The device region 802 is where the plurality of films 811 and 812 described above are formed. The alignment region 805 is formed with alignment marks for positioning the wafer 801 at a standard position before executing steps (1) and (2). Alternatively, the alignment region 805 may be formed within the device region 802.

[0112] Figure 29 This is a top view showing an example of the configuration of alignment marks 851 and 852 according to the second embodiment. The alignment region 805 according to this embodiment includes a first alignment mark 851 for detecting positional deviation of the wafer 801 in the X direction, and a second alignment mark 852 for detecting positional deviation of the wafer 801 in the Y direction.

[0113] Figure 30 1 is a diagram for explaining an example of the configuration of the alignment marks 851 and 852 according to the second embodiment. Figure 30 As shown, the first alignment mark 851 and the second alignment mark 852 have a first region 901, a second region 902, and a third region 903. The first region 901, similar to the first region 21 of the first embodiment, is a region where the reflective film is arranged in an L / S pattern along the Y-axis direction. The second region 902, similar to the second region 22 of the first embodiment, is a region where the reflective film is arranged in an L / S pattern along the X-axis direction. The third region 903 is a region where the reflective film is arranged in a solid or lattice pattern. Furthermore, the first region 901 transmits X-polarized light with a higher transmittance than Y-polarized light and reflects Y-polarized light with a higher reflectance than X-polarized light. The second region 902 transmits Y-polarized light with a higher transmittance than X-polarized light and reflects X-polarized light with a higher reflectance than Y-polarized light. The third region 903 reflects both X-polarized light and Y-polarized light.

[0114] The first region 901 is arranged so that its extension direction is along the X-axis direction. The second region 902 is arranged perpendicular to the extension direction of the first region 901. The third region 903 is arranged in a region where the first region 901 and the second region 902 overlap in a plan view.

[0115] By switching between irradiating the alignment marks 851 and 852 with X-polarized light and Y-polarized light, two types of image information can be acquired. Furthermore, by overlapping the first region 901 and the second region 902 as described above, and arranging the third region 903 in the area where the first and second regions 901 and 902 overlap, the areas of the alignment marks 851 and 852 can be reduced. This allows for highly accurate alignment using alignment marks 851 and 852 that are smaller than in conventional techniques.

[0116] In the first and second embodiments, the material of the reflective film is not particularly limited. Furthermore, in the embodiments, the reflective and transmissive regions may have opposite configurations, as long as the materials can produce a phase difference. Specifically, if the alignment regions 12 and 62 are entirely reflective, the third region becomes a transmissive region.

[0117] While several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention and are included within the invention set forth in the patent claims and their equivalents.

Claims

1. A template having alignment marks, The alignment marks include first marks arranged at a first pitch along a first direction, and second marks arranged at a second pitch along the first direction, at least one of the first marks includes a first region and a third region, at least one of the second marks includes a second region and the third region, the first region has a first pattern arranged in a line and spaced pattern along the first direction, and the second region has a second pattern arranged in a line and spaced pattern along a second direction orthogonal to the first direction. The first region transmits the first polarized light at a higher transmittance than the second polarized light, and reflects the second polarized light at a higher reflectance than the first polarized light, the electric field of the first polarized light vibrates along a first plane including the first direction, and the electric field of the second polarized light vibrates along a second plane orthogonal to the first plane. The second region transmits the second polarized light at a higher transmittance than the first polarized light, and reflects the first polarized light at a higher reflectance than the second polarized light.

2. The template according to claim 1, wherein The third region includes a third pattern arranged in a solid or lattice pattern.

3. The template according to claim 2, wherein: The first pitch and the second pitch are less than 2000 nm.

4. The template according to claim 3, wherein: The pitch between the first pattern and the second pattern is 100 nm or less.

5. The template according to claim 1, wherein The first polarized light is TM polarized light, and the second polarized light is TE polarized light.

6. A workpiece having an alignment mark for adjusting its position when performing a plurality of steps. The alignment marks include first marks arranged at a second pitch along a first direction, and second marks arranged at the first pitch along the first direction, at least one of the first marks includes a first region and a third region, at least one of the second marks includes a second region and the third region, the first region has a first pattern arranged in a line and spaced pattern along the first direction, and the second region has a second pattern arranged in a line and spaced pattern along a second direction orthogonal to the first direction. The first region transmits the first polarized light at a higher transmittance than the second polarized light, and reflects the second polarized light at a higher reflectance than the first polarized light, the electric field of the first polarized light vibrates along a first plane including the first direction, and the electric field of the second polarized light vibrates along a second plane orthogonal to the first plane. The second region transmits the second polarized light at a higher transmittance than the first polarized light, and reflects the first polarized light at a higher reflectance than the second polarized light.

7. An alignment method, comprising: a step of placing a template having a first alignment mark formed thereon and a workpiece having a second alignment mark formed thereon so as to face each other; irradiating the template with a first polarized light having an electric field vibrating along a first plane; a step of acquiring first moiré fringe information associated with the moiré fringe generated by the first polarized light; irradiating the template with a second polarized light having an electric field vibrating along a second plane perpendicular to the first plane from the template side; a step of acquiring second moiré fringe information associated with the moiré fringe generated by the second polarized light; and a step of adjusting the relative position between the template and the workpiece based on the first moiré fringe information and the second moiré fringe information, The first alignment marks include first marks arranged at a first pitch along a first direction, and second marks arranged at a second pitch along the first direction. At least one of the first markers includes a first region and a third region, At least one of the second markers includes the second region and the third region, The first region has a first pattern arranged in lines and spaces along the first direction, The second region has a second pattern arranged in lines and spaces along a second direction orthogonal to the first direction. The second alignment marks include first marks arranged at a second pitch along the first direction, and second marks arranged at a first pitch along the first direction. At least one of the first markers includes a first region and a third region, At least one of the second markers includes the second region and the third region, The first region has a first pattern arranged in lines and spaces along the first direction, The second region has a second pattern arranged in lines and spaces along a second direction orthogonal to the first direction. The first region transmits the first polarized light at a higher transmittance than the second polarized light, and reflects the second polarized light at a higher reflectance than the first polarized light, the electric field of the first polarized light vibrates along a first plane including the first direction, and the electric field of the second polarized light vibrates along a second plane orthogonal to the first plane. The second region transmits the second polarized light at a higher transmittance than the first polarized light, and reflects the first polarized light at a higher reflectance than the second polarized light.

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