Mask layout and device fabrication methods

Abstract

A mask layout and device formation method are disclosed. The mask layout includes: a first sub-layout including a first main pattern area and a marking area protruding from and connected to the first main pattern area, wherein the first main pattern area has a first chip pattern and the marking area has a first stitching mark pattern; a second sub-layout including a second main pattern area for stitching with the first main pattern area, wherein the second main pattern area has a second chip pattern and a second stitching mark pattern located on the side of the second chip pattern, the second stitching mark pattern being disposed on the side of the second sub-layout to be stitched with the first sub-layout, and the second chip pattern being used to stitch with the first chip pattern to obtain a target pattern; wherein the first stitching mark pattern and the second stitching mark pattern are configured to be aligned after the first sub-layout and the second sub-layout are stitched together. This improves the alignment accuracy of the stitching exposure.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and more particularly to a method for forming a mask layout and a device. Background Technology

[0002] With the development of digital technology, semiconductor manufacturing technology, and the arrival of the information age, sensors, as optoelectronic components in the optoelectronic industry, have experienced rapid and ever-changing development. Currently, they are widely used in various fields, each with its own unique customer system requirements. For example, professional imaging applications such as astronomical telescopes, full-frame digital cameras, and medical imaging require large-size sensors. Because these large sensors exceed the image field of a lithography machine, stitching technology is necessary during their manufacturing process.

[0003] As the name suggests, splicing technology involves dividing the pattern into sections during chip manufacturing, exposing them sequentially, and finally splicing them together to form a large-size pattern sensor.

[0004] While existing chip splicing methods can effectively avoid defects such as deformation, discontinuity, and narrowing of lines at the connection points of corresponding spliced ​​chip circuit structures, they lack precise control over the alignment between different parts. Summary of the Invention

[0005] The problem solved by the embodiments of the present invention is to provide a method for forming a mask layout and a device, thereby improving the alignment accuracy of splicing exposure.

[0006] To address the aforementioned problems, this invention provides a mask layout, comprising: a target layout, the target layout including multiple sub-layouts located on the same layer, the multiple sub-layouts being used to form a complete target layout after being stitched together, and each sub-layout having a stitching mark graphic at the stitching position; the sub-layouts including a first sub-layout and a second sub-layout for stitching; the first sub-layout including a first main graphic area and a mark area protruding from and connected to the first main graphic area, the mark area being disposed on the side of the first sub-layout to be stitched, the first main graphic area having a first chip graphic, and the mark area having a first... The second sub-layout includes a splicing mark graphic; the second sub-layout includes a second main graphic area for splicing with the first main graphic area, the second main graphic area having a second chip graphic and a second splicing mark graphic located on the side of the second chip graphic, the second splicing mark graphic being disposed on the side of the second sub-layout to be spliced ​​with the first sub-layout, and the second chip graphic being used to splice with the first chip graphic to obtain a target graphic; wherein, the first splicing mark graphic and the second splicing mark graphic are configured to be aligned after splicing the first sub-layout and the second sub-layout.

[0007] Accordingly, embodiments of the present invention also provide a device formation method, comprising: providing a substrate, the substrate comprising a plurality of sequentially adjacent sub-regions, the plurality of sub-regions being sequentially spliced ​​together to form a complete target region, any two adjacent sub-regions serving as a first region and a second region; providing an exposure pattern, the exposure pattern being formed using a mask pattern as described in any one of claims 1 to 10, the exposure pattern comprising a plurality of sub-patterns, the sub-patterns being connected to the mask pattern... Figure 1 One-to-one correspondence; using the exposure pattern, each of the sub-regions is sequentially stitched and exposed, and the sub-patterns in the exposure pattern correspond one-to-one with the sub-regions; after the stitching exposure, development is performed to form a first main pattern structure located in the first region and a first stitching mark pattern structure located in the second region on the substrate, and the first stitching mark pattern structure is close to the boundary between the first region and the second region; a second main pattern structure and a second stitching mark pattern structure located on the side of the second main pattern structure are formed in the second region of the substrate, and the second stitching mark pattern structure is formed at the position of the first stitching mark pattern structure, wherein the first main pattern structure in the first region and the second main pattern structure in the second region are stitched together to form a complete target pattern structure; alignment detection is performed on the first stitching mark pattern structure and the second stitching mark pattern structure to determine whether the alignment deviation between the first stitching mark pattern structure and the second stitching mark pattern structure is within the allowable deviation range.

[0008] Compared with the prior art, the technical solution of the embodiments of the present invention has the following advantages:

[0009] This invention provides a mask layout. The first sub-layout includes a first main graphic area and a marking area protruding from and connected to the first main graphic area. The marking area is located on one side of the first sub-layout to be stitched together. The first main graphic area has a first chip graphic, and the marking area has a first stitching mark graphic. The second sub-layout includes a second main graphic area for stitching with the first main graphic area. The second main graphic area has a second chip graphic and a second stitching mark graphic located on the side of the second chip graphic. The second stitching mark graphic is located on the side of the second sub-layout to be stitched with the first sub-layout, and the second chip graphic is used to stitch with the first chip graphic to obtain a target graphic. The first and second stitching mark graphics are configured to be aligned after stitching the first and second sub-layouts. This invention provides an embodiment that adds a marker area protruding from the first main graphic area in the first sub-pattern, and this marker area contains a first stitching marker graphic. Simultaneously, a second stitching marker graphic is set in the second main graphic area of ​​the second sub-pattern. Therefore, when a mask based on the mask pattern is used for stitching exposure and development, the graphic structure corresponding to the first stitching marker graphic will form in the area corresponding to the second sub-pattern, while the graphic structure corresponding to the second stitching marker graphic will still form in the area corresponding to the second sub-pattern. Thus, by assessing the alignment of the graphic structures corresponding to the first and second stitching marker graphics, the alignment deviation of the stitching exposure can be determined to be within the allowable deviation range, thereby improving the alignment accuracy of the stitching exposure. Attached Figure Description

[0010] Figure 1 It is the first sub-version Figure 1 Schematic diagram corresponding to the embodiment;

[0011] Figure 2 It is the second sub-version Figure 1 Schematic diagram corresponding to the embodiment;

[0012] Figure 3 This is a schematic diagram of an embodiment of multiple sub-layouts after being spliced ​​together;

[0013] Figure 4 This is a schematic diagram corresponding to one embodiment of the first splicing mark graphic;

[0014] Figure 5 This is a schematic diagram corresponding to one embodiment of the second splicing mark graphic;

[0015] Figure 6 This is a schematic diagram corresponding to an embodiment where the first splicing mark graphic and the second splicing mark graphic are nested together;

[0016] Figures 7 to 11 This is a schematic diagram of each step in one embodiment of the device formation method of the present invention. Detailed Implementation

[0017] The alignment accuracy of current splicing exposure needs improvement. In the existing splicing exposure process using photomasks based on photomask patterns, the chip patterns formed on the substrate cannot be accurately spliced ​​due to the influence of the accuracy deviation of the exposure equipment.

[0018] To address the aforementioned technical problem, this invention provides a mask layout, comprising: a target layout, the target layout including multiple sub-layouts located on the same layer, the multiple sub-layouts being used to form a complete target layout after splicing, and each sub-layout having a splicing mark graphic at the splicing position; the sub-layout including a first sub-layout and a second sub-layout for splicing; the first sub-layout including a first main graphic area and a mark area protruding from and connected to the first main graphic area, the mark area being disposed on the side of the first sub-layout to be spliced, the first main graphic area having a first chip graphic, and the mark area having a first chip graphic. A splicing mark graphic; the second sub-layout includes a second main graphic area for splicing with the first main graphic area, the second main graphic area having a second chip graphic and a second splicing mark graphic located on the side of the second chip graphic, the second splicing mark graphic being disposed on the side of the second sub-layout to be spliced ​​with the first sub-layout, and the second chip graphic being used to splice with the first chip graphic to obtain a target graphic; wherein, the first splicing mark graphic and the second splicing mark graphic are configured such that after the first sub-layout and the second sub-layout are spliced, the first splicing mark graphic and the second splicing mark graphic are aligned.

[0019] In the scheme disclosed in this embodiment of the invention, by adding a mark area protruding from the first main graphic area in the first sub-pattern, and the mark area having a first stitching mark graphic, and simultaneously setting a second stitching mark graphic in the second main graphic area of ​​the second sub-pattern, when a mask made based on the mask pattern is used for stitching exposure and development, the graphic structure corresponding to the first stitching mark graphic will be formed in the area corresponding to the second sub-pattern, while the graphic structure corresponding to the second stitching mark graphic will still be formed in the area corresponding to the second sub-pattern. Thus, by judging the alignment of the graphic structures corresponding to the first and second stitching mark graphics, it can be determined whether the alignment deviation of the stitching exposure is within the allowable deviation range, so as to improve the alignment accuracy of the stitching exposure.

[0020] To make the above-mentioned objects, features and advantages of the embodiments of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0021] Figure 1 It is the first sub-version Figure 1 Schematic diagram corresponding to the embodiment; Figure 2 It is the second sub-version Figure 1 Schematic diagram corresponding to the embodiment; Figure 3 This is a schematic diagram of an embodiment of multiple sub-layouts after being spliced ​​together; Figure 4 This is a schematic diagram corresponding to one embodiment of the first splicing mark graphic; Figure 5 This is a schematic diagram corresponding to one embodiment of the second splicing mark graphic; Figure 6 This is a schematic diagram corresponding to an embodiment where the first splicing mark graphic and the second splicing mark graphic are nested together.

[0022] The mask layout includes: a target layout, which comprises multiple sub-layouts located on the same layer. These sub-layouts are used to form a complete target layout after being stitched together. Each sub-layout has a stitching mark graphic at the stitching position. The sub-layouts include a first sub-layout 300 and a second sub-layout 301 for stitching. The first sub-layout 300 includes a first main graphic area 200A and a mark area 200C protruding from and connected to the first main graphic area 200A. The mark area 200C is located on the side of the first sub-layout 300 to be stitched. The first main graphic area 200A has a first chip graphic 202, and the mark area 200C has a first stitching mark graphic 203. The second sub-layout 300... 01 includes a second main graphic area 200B for splicing with the first main graphic area 200A. The second main graphic area 200B has a second chip graphic 210 and a second splicing mark graphic 205 located on the side of the second chip graphic 210. The second splicing mark graphic 205 is disposed on the side of the second sub-layout 301 to be spliced ​​with the first sub-layout 300, and the second chip graphic 210 is used to splice with the first chip graphic 202 to obtain a target graphic. The first splicing mark graphic 203 and the second splicing mark graphic 205 are configured to be aligned after splicing the first sub-layout 300 and the second sub-layout 301.

[0023] By adding a mark area 200C protruding from the first main graphic area 200A in the first sub-pattern 300, and having a first stitching mark graphic 203 in the mark area 200C, and simultaneously setting a second stitching mark graphic 205 in the second main graphic area 210 of the second sub-pattern 301, when a mask based on the mask pattern is used for stitching exposure and development, the graphic structure corresponding to the first stitching mark graphic 203 will be formed in the area corresponding to the second sub-pattern 301, while the graphic structure corresponding to the second stitching mark graphic 205 will still be formed in the area corresponding to the second sub-pattern 301. Thus, by checking the alignment of the graphic structures corresponding to the first stitching mark graphic 203 and the second stitching mark graphic 205, it can be determined whether the alignment deviation of the stitching exposure is within the allowable deviation range, thereby improving the alignment accuracy of the stitching exposure.

[0024] The plurality of sub-plots are used along a first direction (e.g.) Figure 3 If splicing is achieved in the X direction (as shown in the middle) or the second direction, the first direction is perpendicular to the second direction.

[0025] Specifically, the adjacency direction of the plurality of sub-layouts is determined by the splicing direction of the first sub-layout 300 and the second sub-layout 301. If the first sub-layout 300 and the second sub-layout 301 need to be spliced ​​in a first direction, then the plurality of sub-layouts are adjacent in the first direction; if the first sub-layout 300 and the second sub-layout 301 need to be spliced ​​in a second direction, then the plurality of sub-layouts are adjacent in the second direction. As an example, the plurality of sub-layouts are adjacent along the first direction, which is perpendicular to the second direction.

[0026] As an example, the mask pattern is used to fabricate silicon photonic chips. These chips will be deployed in high-speed signal transmission systems, replacing existing copper stranded wire transmissions. The performance bottleneck of high-performance computing systems has shifted from processors to communication infrastructure, and optical interconnects can provide a high-bandwidth, low-latency solution to address the challenges of bandwidth scalability in future computing systems.

[0027] In this embodiment, the target layout is used to form an optical waveguide structure. The optical waveguide structure is a structure that guides the transmission of light waves. In silicon photonics chips, the primary pattern for passive devices is the waveguide.

[0028] The shape of the first splicing mark graphic 203 includes a bar, a frame, or a cross shape.

[0029] By using a bar, frame, or cross shape, it is easy to obtain two parallel sides for the first splicing mark graphic 203 in the first and second directions respectively. Thus, in the alignment test step, it is convenient to judge the alignment deviation between the first splicing mark graphic 203 and the second splicing mark graphic 205 by the distance between them.

[0030] The first splicing mark graphic 203 includes a direction along the first direction (e.g., Figure 4 A pair of first strip patterns 2032 arranged parallel to each other in the X direction, and along the second direction (as shown in the X direction) Figure 4 A pair of second bar graphics 2031 arranged in parallel (as shown in the Y direction). That is, the first splicing mark graphic 203 includes two first bar graphics 2032 arranged in parallel and two second bar graphics 2031 arranged in parallel.

[0031] By setting a pair of parallel first strip patterns 2032 in the first direction, when a device is fabricated using the pattern of the mask layout through a splicing exposure process, the splicing mark pattern structure corresponding to the first strip pattern 2032 can serve as a fixed reference point. By obtaining the positional relationship between the splicing mark pattern structure corresponding to the second splicing mark pattern 205 and the first splicing mark pattern 203 in the first direction, the alignment accuracy of the splicing exposure can be determined.

[0032] By setting a pair of parallel second strip patterns 2031 in the second direction, when a device is fabricated using the pattern of the mask layout through a splicing exposure process, the splicing mark pattern structure corresponding to the second strip pattern 2031 can serve as a fixed reference point. By obtaining the positional relationship between the second splicing mark pattern 205 and the splicing mark pattern structure corresponding to the first splicing mark pattern 203 in the second direction, the alignment accuracy of the splicing exposure can be determined.

[0033] In this embodiment, the first bar graphic 2032 and the second bar graphic 2031 form a square-shaped first splicing mark graphic 203, so that the alignment in the first direction and the second direction can be monitored simultaneously through a first splicing mark graphic 203.

[0034] The square shape corresponding to the first splicing mark graphic 203 can be closed or open.

[0035] Specifically, "closed" means that adjacent first and second strip patterns are connected, while "non-closed" means that adjacent first and second strip patterns are not connected.

[0036] It should be noted that, in other embodiments, the first bar graph 2032 and the second bar graph 2031 may also be disposed in different marking areas of the first sub-layout 300, so as to monitor the alignment in the second direction and the first direction respectively.

[0037] The shape of the second splicing mark graphic 205 includes a bar, a frame, or a cross shape.

[0038] By using a bar, frame, or cross shape, it is easy to obtain two parallel sides for the second splicing mark graphic 205 in the first and second directions respectively. Thus, in the alignment test step, it is convenient to judge the alignment deviation between the first splicing mark graphic 203 and the second splicing mark graphic 205 by the distance between them.

[0039] The second splicing mark graphic 205 includes along the first direction (e.g., Figure 5 A pair of third strip patterns 2052 arranged parallel to each other in the X direction, and along the second direction (as shown in the X direction) Figure 5 A pair of fourth strip graphics 2051 arranged in parallel (as shown in the Y direction). That is, the second splicing mark graphic 205 includes two parallel third strip graphics 2052 and two parallel fourth strip graphics 2051.

[0040] Accordingly, in this embodiment, the first splicing mark graphic 203 and the second splicing mark graphic 205 are configured such that after splicing the first sub-pattern 300 and the second sub-pattern 301, the first bar graphic 2032 and the third bar graphic 2052 are aligned in a first direction, and the second bar graphic 2031 and the fourth bar graphic 2051 are aligned in a second direction.

[0041] By setting a pair of parallel third strip patterns 2052 in the first direction, the third strip pattern 2052 and the first strip pattern 2032 are parallel to each other in the first direction. By judging the distance between the corresponding graphic structures formed by the third strip pattern 2052 and the first strip pattern 2032 after exposure and development, the alignment accuracy of the splicing exposure process in the second direction can be detected.

[0042] By setting a pair of parallel fourth strip patterns 2051 in the second direction, making the fourth strip pattern 2051 and the second strip pattern 2031 parallel to each other in the second direction, the alignment accuracy of the splicing exposure process in the first direction can be detected by judging the distance between the corresponding graphic structures formed by the fourth strip pattern 2051 and the second strip pattern 2031 after exposure and development.

[0043] In this embodiment, the third strip graphic 2052 and the fourth strip graphic 2051 form a square-shaped second splicing mark graphic 205, so that the alignment in the first direction and the second direction can be monitored simultaneously through a second splicing mark graphic 205.

[0044] The box shape corresponding to the second splicing mark graphic 205 can be closed or open.

[0045] Specifically, "closed" means that adjacent first and second strip patterns are connected, while "non-closed" means that adjacent first and second strip patterns are not connected.

[0046] It should be noted that, in other embodiments, the third bar graphic 2052 and the fourth bar graphic 2051 may also be disposed at different positions in the second sub-layout, thereby matching with the first bar graphic 2032 and the second bar graphic 2031 respectively, so that the first splicing mark graphic and the second splicing mark graphic satisfy the following: after splicing the first sub-layout and the second sub-layout, the first bar graphic 2032 and the third bar graphic 2052 are aligned, and the second bar graphic 2031 and the fourth bar graphic 2051 are aligned.

[0047] like Figure 6 As shown, in this embodiment, the alignment between the first splicing mark graphic 203 and the second splicing mark graphic 205 includes: the first splicing mark graphic 203 and the second splicing mark graphic 205 are nested together.

[0048] Specifically, the first splicing mark pattern 203 and the second splicing mark pattern 205 are nested together, which can be used to determine the alignment deviation of the splicing exposure process in the first direction, and at the same time, can also determine the alignment deviation of the splicing exposure process in the second direction, which can easily improve the efficiency of alignment detection.

[0049] In other embodiments, the first and second bar graphics may also be disposed in different marking areas of the first sub-plot, and the third and fourth bar graphics may also be disposed in different positions of the second sub-plot. Accordingly, the alignment between the first and second splicing mark graphics includes: the first splicing mark graphics being located between the second splicing mark graphics, or the second splicing mark graphics being located between the first splicing mark graphics.

[0050] In this embodiment, the first splicing mark graphic 203 and the second splicing mark graphic 205 have the same shape but different sizes.

[0051] On one hand, the second splicing mark graphic 205 and the first splicing mark graphic 203 have the same shape. In both the first and second directions, the second splicing mark graphic 205 and the first splicing mark graphic 203 have two parallel sides. During the alignment test, this facilitates measuring the difference between the distance between the two parallel sides of the second splicing mark graphic 205 and the first splicing mark graphic 203 in the first direction and a preset distance. Alternatively, the difference between the distance between the two parallel sides of the second splicing mark graphic 205 and the first splicing mark graphic 203 in the second direction and a preset distance can be used to determine the alignment deviation between the second splicing mark graphic 205 and the first splicing mark graphic 203. The preset distance refers to the preset distance between adjacent first and third strip graphic structures, or the preset distance refers to the preset distance between adjacent second and fourth strip graphic structures.

[0052] On the other hand, the second splicing mark pattern 205 and the first splicing mark pattern 203 are different in size. During the device fabrication process, this facilitates the interlocking of the second splicing mark pattern 205 and the first splicing mark pattern 203 after exposure and development, so that the second splicing mark pattern structure corresponding to the second splicing mark pattern 205 and the first splicing mark pattern structure corresponding to the first splicing mark pattern 203 can be interlocked, thereby determining whether the alignment deviation of the splicing exposure is within the allowable deviation range.

[0053] In this embodiment, the first splicing mark graphic 203 and the second splicing mark graphic 205 are configured such that after splicing the first sub-layout 300 and the second sub-layout 301, the distances between adjacent first strip graphics 2032 and third strip graphics 2052 are equal, and the distances between adjacent second strip graphics 2031 and fourth strip graphics 2051 are equal, thereby reducing the complexity of designing the mask layout.

[0054] Either the first splicing mark graphic 203 or the second splicing mark graphic 205 is used as an outer graphic, and the other is used as an inner graphic, wherein the outer graphic is used to surround the inner graphic. As an example, such as Figure 6 As shown, the first splicing mark graphic 203 is used as the outer graphic, and the second splicing mark graphic 205 is used as the inner graphic.

[0055] It should be noted that the side length of the outer pattern should not be too large or too small. If the side length of the outer pattern is too large, it will easily lead to an excessively large space occupied by the outer pattern, resulting in an excessively large mask layout, and the space area used to accommodate the second chip pattern 210 will easily be too small. If the side length of the outer pattern is too small, under the condition that the side length of the inner pattern meets the process requirements, it will easily lead to an excessively small distance in the second direction between adjacent first strip patterns 2032 and third strip patterns 2052, and an excessively small distance in the first direction between adjacent second strip patterns 2031 and fourth strip patterns 2051, increasing the difficulty of alignment between the outer and inner patterns. Therefore, in this embodiment, the side length of the outer pattern is 15µm to 20µm.

[0056] It should also be noted that the side length of the internal pattern should not be too large or too small. If the side length of the internal pattern is too large, the side length of the external pattern will also be too large, resulting in an excessively large mask layout and a small space area for accommodating the second chip pattern 210. If the side length of the internal pattern is too small, the process of forming the splicing mark pattern structure corresponding to the internal pattern will become more difficult during device fabrication. Therefore, in this embodiment, the side length of the internal pattern is 5µm to 10µm.

[0057] The distance d2 between adjacent first bar patterns 2032 and third bar patterns 2052 should not be too large or too small. If the distance d2 between the first bar pattern 2032 and third bar pattern 2052 is too large, the side length of the outer pattern may be too large, even if the side length of the inner pattern meets the process requirements, thus causing the outer pattern to occupy too much space in the mask pattern. If the distance d2 between the first bar pattern 2032 and third bar pattern 2052 is too small, the process difficulty of forming the first bar pattern 2032 and third bar pattern 2052 during the splicing exposure process is increased. In other words, the distance d2 is difficult to cover the normal alignment deviation of the exposure process in the second direction. Therefore, in this embodiment, the distance d2 between adjacent first bar patterns 2032 and third bar patterns 2052 is 4µm to 6µm.

[0058] The distance d1 between adjacent second stripe patterns 2031 and fourth stripe patterns 2051 should not be too large or too small. If the distance d1 between the second stripe pattern 2031 and fourth stripe pattern 2051 is too large, the side length of the outer pattern may be too large, even if the side length of the inner pattern meets the process requirements, thus causing the outer pattern to occupy too much space in the mask pattern. If the distance d1 between the second stripe pattern 2031 and fourth stripe pattern 2051 is too small, the process difficulty of forming the second stripe pattern 2031 and fourth stripe pattern 2051 during the splicing exposure process will increase. In other words, the distance d2 may not be able to cover the normal alignment deviation of the exposure process in the second direction. Therefore, in this embodiment, the distance d2 between adjacent second stripe patterns 2031 and third stripe patterns 2051 is 4µm to 6µm.

[0059] In this embodiment, the alignment between the first splicing mark graphic 203 and the second splicing mark graphic 205 includes: the first splicing mark graphic 203 and the second splicing mark graphic 205 are nested together.

[0060] Specifically, the first splicing mark pattern 203 and the second splicing mark pattern 205 are nested together, which can determine the alignment deviation of the first splicing mark pattern 203 and the second splicing mark pattern 205 in the first direction, and can also determine the alignment deviation of the first splicing mark pattern 203 and the second splicing mark pattern 205 in the second direction.

[0061] Figures 7 to 11 This is a schematic diagram of each step in one embodiment of the device formation method of the present invention.

[0062] refer to Figures 7 to 8 , Figure 7 It is a top view. Figure 8 yes Figure 7 A cross-sectional view along the AB direction provides a base, the base comprising a plurality of sequentially adjacent sub-regions, the plurality of sub-regions being sequentially spliced ​​together to form the complete target region 120, any two adjacent sub-regions being designated as the first region 100A and the second region 100B.

[0063] The substrate includes a substrate 100 and a photomask layer 101 covering the substrate 100.

[0064] The substrate 100 provides the basis for the process operation of the exposure method.

[0065] In this embodiment, substrate 100 is a silicon substrate. In other embodiments, the substrate material may also be germanium, silicon germanide, silicon carbide, gallium arsenide, or indium gallium dihydrogen phosphate, or other materials. The substrate may also be a silicon-on-insulator substrate or a germanium-on-insulator substrate, or other types of substrates. The substrate material may be suitable for process requirements or easy to integrate.

[0066] The photomask layer 101 provides the technological basis for the subsequent formation of the first main pattern structure, the first splicing mark pattern structure, the second main pattern structure, and the second splicing mark pattern structure.

[0067] Specifically, the photomask layer 101 is subsequently exposed and developed to form a patterned photomask layer 101, which is used to provide a first main pattern structure, a first splicing mark pattern structure, a second main pattern structure, and a second splicing mark pattern structure.

[0068] In this embodiment, the material of the photomask layer 101 is photoresist.

[0069] The multiple sub-regions in the first direction (e.g.) Figure 7 (as shown in the X direction) or the second direction (e.g.) Figure 7 (As shown in the Y direction) are adjacent to each other, and the first direction is perpendicular to the second direction.

[0070] Specifically, the adjacency direction of the plurality of sub-regions is determined by the splicing direction of the subsequently formed first and second main graphic structures. If the first and second main graphic structures need to be spliced ​​in a first direction, then the plurality of sub-regions are adjacent in the first direction; if the first and second main graphic structures need to be spliced ​​in a second direction, then the plurality of sub-regions are adjacent in the second direction. As an example, the plurality of sub-regions are adjacent in the first direction, which is perpendicular to the second direction.

[0071] In this embodiment, the target region 120 is used to form an optical waveguide structure.

[0072] The optical waveguide structure is a structure that guides the transmission of light waves.

[0073] In this embodiment, any two adjacent sub-regions are designated as the first region 100A and the second region 100B. The first region 100A is used to form a first main pattern structure, and the second region 100B is used to form a second main pattern structure. The first main pattern structure in the first region 100A and the second main pattern structure in the second region 100B are joined together to form a complete target pattern structure. In this embodiment, the target pattern structure is an optical waveguide structure.

[0074] In this embodiment, the forming method further includes: providing an exposure pattern, wherein the exposure pattern is formed using the mask pattern described in the foregoing embodiment, and the exposure pattern includes multiple sub-patterns, wherein the sub-patterns and the sub-mask are... Figure 1 One-to-one correspondence.

[0075] The exposed pattern refers to the pattern used for pattern transfer during exposure, which transfers the exposed pattern onto the substrate through exposure.

[0076] In this embodiment, the step of providing the exposure pattern includes: providing a mask with the exposure pattern.

[0077] A photomask is prepared using the photomask pattern described in the foregoing embodiments, and then the photomask is used for subsequent exposure processes. Accordingly, the photomask has patterns corresponding to those in the sub-pattern.

[0078] In this embodiment, in the mask layout described in the previous embodiment, the target layout includes multiple sub-layouts located on the same layer. Therefore, the graphics of each sub-layout are all set in the same mask. Only the exposure position on the mask needs to be changed to achieve spliced ​​exposure.

[0079] refer to Figures 9 to 11 The exposure pattern is used to sequentially stitch together the exposure of each of the sub-regions, and the sub-patterns in the exposure pattern correspond one-to-one with the sub-regions. After the stitching exposure, development is performed to form a first main pattern structure 102 located in the first region 100A and a first stitching mark pattern structure 103 located in the second region 100B on the substrate. The first stitching mark pattern structure 103 is located near the boundary between the first region 100A and the second region 100B. A second main pattern structure 110 and a second stitching mark pattern structure 105 located on the side of the second main pattern structure 110 are formed in the second region 100B of the substrate. The second stitching mark pattern structure 105 is formed at the position of the first stitching mark pattern structure 103. The first main pattern structure 102 in the first region 100A and the second main pattern structure 110 in the second region 100B are stitched together to form a complete target pattern structure.

[0080] in, Figure 9 The diagram shows the splicing of the first main graphic structure in the first area and the second main graphic structure in the second area. Figure 10 It shows Figure 9 A schematic diagram along the AB direction. Figure 11 A schematic diagram showing the alignment of the second splicing mark graphic structure 105 with the first splicing mark graphic structure 103 is shown.

[0081] Specifically, the photomask layer 101 of each of the sub-regions is spliced ​​and exposed sequentially using the exposure pattern, thereby forming a patterned photomask layer 101 after development, and correspondingly obtaining a first main pattern structure 102, a first splicing mark pattern structure 103, a second main pattern structure 110, and a second splicing mark pattern structure 105.

[0082] By splicing and exposing the various sub-regions, and then developing them after splicing and exposing, the exposed pattern on the mask is transferred to the photomask layer 101. The first main pattern structure 102 in the first region 100A and the second main pattern structure 110 in the second region 100B are spliced ​​together to form a complete target pattern structure, which is an etching mask for subsequent pattern transfer.

[0083] The first main pattern structure 102 corresponds to the first chip pattern in the mask layout, the second main pattern structure 110 corresponds to the second chip pattern in the mask layout, the first splicing mark pattern structure 103 corresponds to the first splicing mark pattern in the mask layout, and the second splicing mark pattern structure 105 corresponds to the second splicing mark pattern in the mask layout.

[0084] The first main pattern structure 102 serves as an etching mask for etching the substrate 100 in subsequent forming processes. The first splicing mark pattern structure 103 is used in subsequent alignment detection to determine whether the first main pattern structure 102 and the second main pattern structure are within the alignment deviation range.

[0085] In order to enable the physical splicing of the first main graphic structure 102 and the second main graphic structure in the future, the first main graphic structure 102 needs to be close to the boundary between the first area 100A and the second area 100B.

[0086] It should also be noted that the first stitching mark graphic structure 103 is formed in the second area 100B. By checking the alignment of the first stitching mark graphic structure 103 and the second stitching mark graphic structure, it is determined whether the alignment deviation between the first stitching mark graphic structure and the second stitching mark graphic structure is within the allowable deviation range, so as to improve the alignment accuracy of stitching exposure.

[0087] Specifically, in the step of performing the first exposure on the first area 100A, the shape of the first splicing mark graphic structure 103 includes a bar shape, a frame shape, or a cross shape.

[0088] By using a bar, frame, or cross shape, it is easy to make the first splicing mark graphic structure 103 have two parallel sides in the first and second directions respectively. Thus, in the alignment test step, it is convenient to judge the alignment deviation between the first splicing mark graphic structure 103 and the second splicing mark graphic 105 by measuring the distance between them.

[0089] refer to Figure 11 In this embodiment, the first splicing mark graphic structure 103 includes a pair of first strip graphic structures 1032 arranged parallel to each other along a first direction, and a pair of second strip graphic structures 1031 arranged parallel to each other along a second direction. That is, the first splicing mark graphic structure 103 includes two parallel first strip graphic structures 1032 and two parallel second strip graphic structures 1031.

[0090] By setting a pair of parallel first strip pattern structures 1032 in the first direction, the first strip pattern structure 1032 can serve as a fixed reference point. By obtaining the positional relationship between the second stitching mark pattern structure 105 and the first stitching mark pattern structure 103 in the first direction, the alignment accuracy of the stitching exposure can be determined.

[0091] By setting a pair of parallel first strip pattern structures 1032 in the second direction, the first strip pattern structure 1032 can serve as a fixed reference point. By obtaining the positional relationship between the second stitching mark pattern structure 105 and the first stitching mark pattern structure 103 in the second direction, the alignment accuracy of the stitching exposure can be determined.

[0092] In this embodiment, the first strip graphic structure 1032 and the second strip graphic structure 1031 form a square-shaped first splicing mark graphic structure 103, so that the alignment in the first direction and the second direction can be monitored simultaneously through a first splicing mark graphic structure 103.

[0093] The square shape corresponding to the first splicing mark graphic structure 103 can be closed or open.

[0094] Specifically, "closed" means that adjacent first and second strip patterns are connected, while "non-closed" means that adjacent first and second strip patterns are not connected.

[0095] It should be noted that the second stitching mark graphic structure 105 is formed at the position of the first stitching mark graphic structure 103. By comparing the alignment of the second stitching mark graphic structure 105 and the first stitching mark graphic structure 103, it is determined whether the alignment deviation of the stitching exposure is within the allowable deviation range, so as to improve the alignment accuracy between the second main graphic structure 110 and the first main graphic structure 102.

[0096] The shape of the second splicing mark graphic structure 105 includes a bar, a frame, or a cross shape.

[0097] By using a bar, frame, or cross shape, it is easy to make the second splicing mark graphic structure 105 have two parallel sides in the first and second directions respectively. Thus, in the alignment test step, it is convenient to judge the alignment deviation between the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 by the distance between them.

[0098] In this embodiment, the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 are nested together, which can determine the alignment deviation of the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 in the first direction, and can also determine the alignment deviation of the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 in the second direction, thereby providing convenience for subsequent alignment tests.

[0099] In this embodiment, the second splicing mark graphic structure 105 and the first splicing mark graphic structure 103 have the same shape but different sizes.

[0100] On one hand, the second splicing mark graphic structure 105 and the first splicing mark graphic structure 103 have the same shape. In both the first and second directions, the second splicing mark graphic structure 105 and the first splicing mark graphic structure 103 have two parallel sides. During the alignment test, this facilitates measuring the difference between the distance between the two parallel sides of the second splicing mark graphic structure 105 and the first splicing mark graphic structure 103 in the first direction and a preset distance. Alternatively, the difference between the distance between the two parallel sides of the second splicing mark graphic structure 105 and the first splicing mark graphic structure 103 in the second direction and a preset distance can be used to determine the alignment deviation between the second splicing mark graphic structure 105 and the first splicing mark graphic structure 103. The preset distance refers to the preset distance between adjacent first and third strip graphic structures, or the preset distance refers to the preset distance between adjacent second and fourth strip graphic structures.

[0101] On the other hand, the second splicing mark graphic structure 105 and the first splicing mark graphic structure 103 are different in size, which makes it easier for the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 to be nested together, thereby determining whether the alignment deviation of the splicing exposure is within the allowable deviation range.

[0102] refer to Figure 11 In this embodiment, the second splicing mark graphic structure 105 includes a first direction (such as...). Figure 11 A pair of third strip graphic structures 1052 arranged in parallel (as shown in the X direction), and along the second direction (as shown in the X direction) Figure 11 (As shown in the Y direction) A pair of fourth strip graphic structures 1051 arranged in parallel. That is, the second splicing mark graphic structure 105 includes two parallel third strip graphic structures 1052 and two parallel fourth strip graphic structures 1051.

[0103] By setting a pair of parallel third strip graphic structures 1052 in the first direction, the third strip graphic structure 1052 can serve as a fixed reference point. By obtaining the positional relationship between the second stitching mark graphic structure 105 and the first stitching mark graphic structure 103 in the first direction, the alignment accuracy of the stitching exposure can be determined.

[0104] By setting a pair of parallel fourth strip graphic structures 1051 in the second direction, the fourth strip graphic structure 1051 can serve as a fixed reference point. By obtaining the positional relationship between the second stitching mark graphic structure 105 and the first stitching mark graphic structure 103 in the second direction, the alignment accuracy of the stitching exposure can be determined.

[0105] refer to Figure 11 Alignment detection is performed on the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 to determine whether the alignment deviation of the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 is within the allowable deviation range.

[0106] Specifically, by determining whether the alignment deviation is within the allowable deviation range, the alignment accuracy of the splicing exposure is improved, thereby improving the alignment accuracy between the first main pattern structure 102 and the second main pattern structure 110, and thus improving the performance of the formed device.

[0107] In this embodiment, the step of aligning the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 includes: obtaining the distance between adjacent first strip graphic structures 1032 and third strip graphic structures 1052, and the distance between adjacent second strip graphic structures 1031 and fourth strip graphic structures 1051, as the first directional distance D1 and the second directional distance D2; obtaining the difference between the first directional distance D1 and the preset distance between adjacent first strip graphic structures 1032 and third strip graphic structures 1052, as the first preset difference; determining whether the first preset difference is within the first preset difference range, and when the first preset difference is within the first preset difference range, determining that the first splicing mark graphic structure 1032 is within the first preset difference range. 3. Alignment of the first and second splicing mark graphic structures 103 and 105 in the first direction is achieved; otherwise, alignment of the first and second splicing mark graphic structures 103 and 105 in the first direction is determined to be unsuccessful. The difference between the distance D2 in the second direction and the preset distance between the second and adjacent second strip graphic structures 1031 and fourth strip graphic structures 1051 is obtained as the second preset difference value. It is determined whether the second preset difference value is within the range of the second preset difference value. If the second preset difference value is within the range of the second preset difference value, alignment of the first and second splicing mark graphic structures 103 and 105 in the second direction is determined to be achieved; otherwise, alignment of the first and second splicing mark graphic structures 103 and 105 in the second direction is determined to be unsuccessful.

[0108] Determine the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 respectively in the first direction (e.g., Figure 11 Alignment deviation in the X direction (as shown in the middle X direction), and alignment deviation of the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 in the second direction (as shown in the middle X direction). Figure 11 The alignment deviation in the Y direction (as shown in the middle) ensures that the alignment deviations of the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 in the first and second directions both meet the allowable deviation range of the process, thereby enabling the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 to achieve complete alignment.

[0109] The preset distance between adjacent first strip pattern structure 1032 and third strip pattern structure 1052 is defined as L1, and the first preset difference = first direction distance D1 - preset distance L1.

[0110] It should be noted that the first preset difference range should not be too large. When the distance D1 in the first direction is less than the preset distance L1, if the first preset difference range is too small, that is, the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 fail to achieve complete alignment in the first direction. Therefore, the first preset difference range is -50nm to 0nm. When the distance D1 in the first direction is greater than the preset distance L1, if the first preset difference range is too large, that is, the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 fail to achieve complete alignment in the first direction. Therefore, the first preset difference range is 0nm to 50nm. In summary, the first preset difference range is -50nm to 50nm.

[0111] The preset distance between adjacent second strip graphic structure 1031 and fourth strip graphic structure 1051 is defined as L2, and the second preset difference = second direction distance D2 - preset distance L2.

[0112] It should be noted that the second preset difference range should not be too large. When the distance D2 in the second direction is less than the preset distance L1, if the second preset difference range is too small, that is, the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 fail to achieve complete alignment in the second direction. Therefore, the first preset difference range is -50nm to 0nm. When the distance D2 in the second direction is less than the preset distance L1, if the second preset difference range is too large, that is, the first splicing mark graphic structure 103 and the second splicing mark graphic structure 105 fail to achieve complete alignment in the second direction. Therefore, the first preset difference range is 0nm to 50nm. In summary, the first preset difference range is -50nm to 50nm.

[0113] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A mask layout, characterized in that, include: The target map includes multiple sub-maps located on the same layer. The multiple sub-maps are used to form a complete target map after being spliced ​​together. Each sub-map has a splicing mark graphic at the splicing position. The sub-maps include a first sub-map and a second sub-map for splicing. The first sub-layout includes a first main graphic area and a marking area that protrudes from and is connected to the first main graphic area. The marking area is located on the side of the first sub-layout to be spliced. The first main graphic area has a first chip graphic, and the marking area has a first splicing marking graphic. The second sub-layout includes a second main graphic area for splicing with the first main graphic area. The second main graphic area has a second chip graphic and a second splicing mark graphic located on the side of the second chip graphic. The second splicing mark graphic is set on the side of the second sub-layout to be spliced ​​with the first sub-layout, and the second chip graphic is used to splice with the first chip graphic to obtain the target graphic. Wherein, the first splicing mark graphic and the second splicing mark graphic are configured such that after splicing the first sub-page and the second sub-page, the first splicing mark graphic and the second splicing mark graphic are aligned, wherein the alignment between the first splicing mark graphic and the second splicing mark graphic includes: the first splicing mark graphic and the second splicing mark graphic are nested together.

2. The mask layout as described in claim 1, characterized in that, The shape of the first splicing mark graphic includes a bar, a frame, or a cross shape, and the shape of the second splicing mark graphic includes a bar, a frame, or a cross shape.

3. The mask layout as described in claim 1, characterized in that, The first splicing mark graphic and the second splicing mark graphic have the same shape but different sizes.

4. The mask pattern as described in any one of claims 1 to 3, characterized in that, The plurality of sub-plots are used to splice together along a first direction or a second direction, wherein the first direction is perpendicular to the second direction; The first splicing mark graphic includes a pair of first strip graphics arranged parallel to the first direction, and a pair of second strip graphics arranged parallel to the second direction; The second splicing mark graphic includes a pair of third strip graphics arranged parallel to the first direction, and a pair of fourth strip graphics arranged parallel to the second direction; The first splicing mark graphic and the second splicing mark graphic are configured such that, after splicing the first sub-map and the second sub-map, the first bar graphic and the third bar graphic are aligned in a first direction, and the second bar graphic and the fourth bar graphic are aligned in a second direction.

5. The mask layout as described in claim 4, characterized in that, The first and second splicing mark graphics are configured such that, after splicing the first and second sub-pages, the distances between adjacent first and third bar graphics are equal, and the distances between adjacent second and fourth bar graphics are equal.

6. The mask layout as described in claim 5, characterized in that, The distance between adjacent first and third bar patterns is 4µm to 6µm; the distance between adjacent second and fourth bar patterns is 4µm to 6µm.

7. The mask layout as described in claim 4, characterized in that, Alignment between the first splicing mark graphic and the second splicing mark graphic includes: the first splicing mark graphic and the second splicing mark graphic being nested together; The first strip graphic and the second strip graphic form a square-shaped first splicing mark graphic, and the square shape can be closed or open; The third and fourth stripes form a second spliced ​​marker graphic in the shape of a square, which may be closed or open.

8. The mask layout as described in claim 7, characterized in that, Either the first splicing mark graphic or the second splicing mark graphic is used as an outer graphic, and the other is used as an inner graphic, wherein the outer graphic is used to surround the inner graphic; The outer pattern has a side length of 15µm to 20µm, and the inner pattern has a side length of 5µm to 10µm.

9. The mask layout as described in claim 1, characterized in that, The target layout is used to form an optical waveguide structure.

10. A method for forming a device, characterized in that, include: A base is provided, the base comprising a plurality of sequentially adjacent sub-regions, the plurality of sub-regions being sequentially spliced ​​together to form a complete target region, and any two adjacent sub-regions being designated as a first region and a second region; An exposure pattern is provided, the exposure pattern being formed using a mask layout according to any one of claims 1 to 9, the exposure pattern comprising a plurality of sub-patterns, the sub-patterns corresponding one-to-one with the sub-layout; The exposure pattern is used to sequentially stitch together and expose each of the sub-regions, and the sub-patterns in the exposure pattern correspond one-to-one with the sub-regions; After the stitching exposure, development is performed to form a first main graphic structure in the first area and a first stitching mark graphic structure in the second area on the substrate. The first stitching mark graphic structure is located near the boundary between the first and second areas. In the second area of ​​the substrate, a second main graphic structure and a second stitching mark graphic structure located on the side of the second main graphic structure are formed. The second stitching mark graphic structure is formed at the position of the first stitching mark graphic structure. The first main graphic structure in the first area and the second main graphic structure in the second area are stitched together to form a complete target graphic structure. Alignment detection is performed on the first and second splicing mark graphic structures to determine whether the alignment deviation between the first and second splicing mark graphic structures is within the allowable deviation range.

11. The device formation method as described in claim 10, characterized in that, The plurality of sub-regions are adjacent to each other in a first direction or a second direction, wherein the first direction is perpendicular to the second direction; The first splicing mark graphic structure includes a pair of first strip graphic structures arranged parallel to each other along a first direction, and a pair of second strip graphic structures arranged parallel to each other along a second direction; The second splicing mark graphic structure includes a pair of third strip graphic structures arranged parallel to each other in the first direction, and a pair of fourth strip graphic structures arranged parallel to each other in the second direction; The step of aligning the first splicing mark graphic structure and the second splicing mark graphic structure includes: obtaining the distance between adjacent first strip graphic structures and third strip graphic structures, and the distance between adjacent second strip graphic structures and fourth strip graphic structures, as the first directional distance and the second directional distance; The difference between the distance in the first direction and the preset distance between the first strip graphic structure and the adjacent first strip graphic structure and third strip graphic structure is obtained as the first preset difference value; it is determined whether the first preset difference value is within the first preset difference value range. When the first preset difference value is within the first preset difference value range, it is determined that the first splicing mark graphic structure and the second splicing mark graphic structure are aligned in the first direction; otherwise, it is determined that the first splicing mark graphic structure and the second splicing mark graphic structure have failed to be aligned in the first direction. The difference between the distance in the second direction and the preset distance between the second and fourth strip graphic structures is obtained as the second preset difference. It is then determined whether the second preset difference is within the range of the second preset difference. If the second preset difference is within the range of the second preset difference, it is determined that the first splicing mark graphic structure and the second splicing mark graphic structure are aligned in the second direction. Otherwise, it is determined that the first splicing mark graphic structure and the second splicing mark graphic structure have failed to be aligned in the second direction.

12. The device formation method as claimed in claim 11, characterized in that, The first preset difference range is -50nm to 50nm, and the second preset difference range is -50nm to 50nm.

13. The device formation method as described in claim 10, characterized in that, The step of providing the exposure pattern includes: providing a mask having the exposure pattern.

14. The device formation method as described in claim 10, characterized in that, In the step of providing a substrate, the substrate includes a substrate and a photomask layer covering the substrate; The photomask layers of each sub-region are sequentially exposed using the exposure pattern.

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