Cutting channel structure of mask and wafer

Abstract

The utility model provides a mask and a cutting channel structure of a wafer, the mask comprises a device pattern area, and a circuit pattern is arranged in the device pattern area; the cutting channel pattern area surrounds the device pattern area, and the cutting channel pattern area is provided with a measuring pattern; wherein the shape of the measuring pattern is the same as that of the circuit pattern, and the measuring pattern and the circuit pattern are arranged in an equal proportion. The utility model provides a cutting channel structure of a mask and a wafer, which can obviously improve the measurement accuracy of critical dimension (CD).

Description

Technical Field

[0001] The utility model relates to the field of semiconductors, in particular to a mask plate and a cutting path structure of a wafer. Background Art

[0002] The critical dimension (CD) is an important data reflecting the semiconductor process. The critical dimension (CD) may include data such as the line width and line spacing of the main circuit diagram formed on the photoresist on the surface of the wafer. At present, during the etching process, when it is necessary to measure the critical dimension (CD) of the curve line in the main circuit diagram, the main circuit diagram is directly measured through a scanning electron microscope. However, the high-energy electrons of the scanning electron microscope will have an adverse effect on the photoresist of the main circuit diagram, resulting in a deviation between the actual critical dimension (CD) and the measured critical dimension (CD). Utility Model Content

[0003] The utility model aims to provide a mask plate and a cutting road structure of a wafer. When a measurement pattern formed by the mask plate is used to measure a critical dimension (CD), the curve lines on the main circuit diagram can be measured and the accuracy of the measured critical dimension (CD) can be significantly improved.

[0004] In order to solve the above technical problems, the utility model is realized by the following technical solutions:

[0005] The utility model provides a mask plate, comprising:

[0006] A device pattern area, wherein a circuit pattern is arranged in the device pattern area;

[0007] A cutting path pattern area, wherein the cutting path pattern area surrounds the device pattern area and is provided with a measurement pattern;

[0008] The measurement pattern and the circuit pattern have the same shape, and are arranged in equal proportion to each other.

[0009] In one embodiment of the present invention, the circuit pattern and the measurement pattern are arranged periodically, at equal intervals or in equal proportions.

[0010] In one embodiment of the present invention, the measurement graph includes a plurality of curved lines, a plurality of straight lines and / or a plurality of broken lines;

[0011] The measurement graph is formed by arranging a plurality of the curved lines, a plurality of the straight lines or a plurality of the broken lines separately;

[0012] Alternatively, the measurement pattern is formed by combining and arranging a plurality of the curved lines, a plurality of the straight lines and a plurality of the broken lines.

[0013] In one embodiment of the present invention, the shape of the curved line or the broken line is a ring line, and a plurality of the ring lines are arranged at the same center.

[0014] In one embodiment of the utility model, in the measurement figure, the arrangement of multiple curved lines, multiple straight lines and / or multiple broken line lines is formed by translating one of the lines, or the arrangement of multiple curved lines, multiple straight lines and / or multiple broken line lines is formed by rotating one of the lines and then translating it.

[0015] In one embodiment of the present invention, the curved line includes at least one of a circular line, a wavy line, an arc line, a U-shaped line, a C-shaped line or an S-shaped line.

[0016] In one embodiment of the present invention, the shape of the curved line is a spiral line, and in the spiral line, two adjacent circles of lines are arranged at equal intervals or in equal proportions.

[0017] In one embodiment of the present invention, the shape of the straight line is similar to a spiral line, the trajectory size of the straight line increases in a clockwise or counterclockwise direction, and two adjacent circles of the straight line are arranged at equal intervals or in equal proportions.

[0018] In one embodiment of the present invention, the cutting path pattern area further includes a redundant pattern, and the redundant pattern is arranged on one side of the measurement pattern.

[0019] The utility model further provides a wafer cutting path structure, characterized in that the cutting path structure is applied with any of the above-mentioned mask plates, and comprises:

[0020] a cutting road body, wherein the cutting road body corresponds to a cutting road pattern area of ​​the mask; and

[0021] A test pattern is arranged on the cutting path body, and the test pattern is a scaled pattern of the measurement pattern on the mask.

[0022] As described above, the utility model provides a mask plate and a cutting path structure of a wafer. Based on the curve pattern on the mask plate, a measurement pattern can be formed on the cutting path of the wafer. By measuring the critical dimension (CD) of the measurement pattern, the critical dimension (CD) of the curve line on the main circuit diagram can be measured, thereby avoiding adverse effects on the photoresist of the main circuit diagram and significantly improving the measurement accuracy of the critical dimension (CD). An unexpected effect is that the mask plate is also filled with redundant patterns, and redundant patterns with the same shape as the redundant patterns can be formed on the cutting path of the wafer, which can reduce the difference between the pattern density on the cutting path of the wafer and the pattern density on the main circuit diagram, reduce the influence of the pattern density difference on the critical dimension (CD), and significantly improve the measurement accuracy of the critical dimension (CD).

[0023] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 It is a structural diagram of a mask in one embodiment of the utility model.

[0026] Figure 2 It is an exemplary structural diagram of a measurement pattern in one embodiment of the utility model.

[0027] Figure 3 This is an exemplary structural diagram of a measurement graph in another embodiment of the present invention.

[0028] Figure 4 This is an exemplary structural diagram of a measurement graph in another embodiment of the present invention.

[0029] Figure 5 This is an exemplary structural diagram of a measurement graph in another embodiment of the present invention.

[0030] Figure 6 This is an exemplary structural diagram of a measurement graph in another embodiment of the present invention.

[0031] Figure 7 This is a structural diagram of a mask plate filled with redundant patterns in one embodiment of the utility model.

[0032] In the figure: 10, mask; 20, device pattern area; 30, cutting line pattern area; 40, measurement pattern; 50, redundant pattern. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0035] See also Figure 1 , Figure 1 A mask is provided. First of all, it should be explained that the mask refers to a substrate carrying a design pattern. Among them, the design pattern on the mask 10 can be divided into a design pattern on a device pattern area 20 and a design pattern on a cutting road pattern area 30, and the cutting road pattern area 30 surrounds the device pattern area 20. The device pattern area 20 can be opposite to the main circuit diagram area on the surface of the wafer. In the photolithography process, the design pattern of the device pattern area 20 can form a main circuit diagram on the photoresist in the main circuit diagram area. The cutting road pattern area 30 can be opposite to the cutting road on the wafer. In the photolithography operation, the design pattern of the cutting road pattern area 30 can form a measurement pattern on the photoresist of the wafer cutting road.

[0036] See also Figure 1The mask provided by the utility model can be applied to the scene of measuring the critical dimensions of the curve lines in the above-mentioned main circuit diagram to improve the accuracy of the measurement data. On the mask 10, a circuit pattern can be set in the device pattern area 20. Using the circuit pattern, in the photolithography process, a curve line pattern proportional to the circuit pattern can be formed on the photoresist in the main circuit diagram area on the wafer. For the critical dimensions (CD) of the curve lines in the main circuit diagram area, the spacing between the curve lines and the line width of the curve lines can be included. Since directly measuring the critical dimensions (CD) of the main circuit diagram area will have an adverse effect on the photoresist, thereby causing inaccurate measurement data of the critical dimensions, in order to avoid directly measuring the main circuit diagram area, a measurement pattern 40 can be designed in the cutting path pattern area 30 of the mask.

[0037] Specifically, the measurement pattern 40 can be designed to be the same shape as the circuit pattern and set in equal proportion. In the photolithography operation, after the circuit pattern on the mask 10 and the measurement pattern 40 undergo the same photolithography operation, a pattern similar to the circuit pattern can be formed on the main circuit pattern area on the wafer, and a test pattern similar to the measurement pattern 40 can be formed on the main body of the cutting path of the wafer. At this time, the critical dimension (CD) of the test pattern and the critical dimension (CD) of the pattern on the main circuit pattern also have a corresponding proportional relationship. By measuring the critical dimension (CD) of the test pattern, the critical dimension (CD) of the pattern on the main circuit pattern can be obtained according to the corresponding proportion. Thereby, the adverse effect on the photoresist on the main circuit pattern during measurement is significantly reduced, and the accuracy of the measurement data is improved.

[0038] It should be noted that the specific ratio of the proportional relationship between the measurement pattern 40 and the circuit pattern may not be limited. For example, the predetermined ratio of the measurement pattern 40 to the circuit pattern is set to 1:1. For another example, the predetermined ratio of the measurement pattern 40 to the circuit pattern is set to 1:10. Of course, other ratios are also possible. Specifically, the setting ratio of the measurement pattern 40 relative to the circuit pattern can be measured based on the actual width of the cutting road pattern area 30 to ensure that the maximum size of the measurement pattern 40 in the width direction of the cutting road pattern area 30 can be smaller than the width of the cutting road pattern area 30.

[0039] See also Figure 1 The circuit patterns and measurement patterns 40 in the device pattern area 20 may be arranged periodically, arranged at equal intervals, or arranged in equal proportions. It should be noted that in the equal interval arrangement, the intervals between adjacent lines are equal and the width of each line is the same.

[0040] Specific, for example Figure 2As shown, the equally spaced arrangement may be a plurality of concentrically arranged annular lines, and the spacing between adjacent annular lines is equal, and the width of each annular line is equal. The annular line may be a circular ring, or a polygonal ring, such as a triangular ring, a quadrilateral ring, a pentagonal ring, etc. The annular line may also be an elliptical ring, a square ring with four corners being curved, or other rings with periodic curves.

[0041] For another example, the equal spacing arrangement may be a plurality of U-shaped lines, C-shaped lines, S-shaped lines or other curved lines with the same opening direction, and the spacing between adjacent U-shaped lines, C-shaped lines, S-shaped lines or other curved lines is equal, and the width of each U-shaped line, C-shaped line, S-shaped line or other curved line is equal. The equal proportion arrangement is similar to the equal spacing arrangement, and the only difference is that the spacing between adjacent line patterns in the circuit pattern is arranged in proportion.

[0042] See also Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 The measurement pattern 40 includes a plurality of curved lines, a plurality of straight lines and / or a plurality of broken lines. The measurement pattern 40 can be formed by arranging a plurality of curved lines, a plurality of straight lines or a plurality of broken lines separately, or by arranging a plurality of curved lines, a plurality of straight lines and a plurality of broken lines in combination.

[0043] The arrangement of multiple curved lines, multiple straight lines and / or multiple broken lines can be formed by translating one of the lines. Or the arrangement of multiple curved lines, multiple straight lines and / or multiple broken lines can be formed by translating one of the lines after rotation. For example, the periodic arrangement can be parallel arranged wavy lines, and the spacing between adjacent wavy lines is equal, and the width of each wavy line is equal. Specifically, a periodically arranged measurement pattern 40 can be formed by translating a wavy line, that is, the measurement pattern 40 is arranged axially symmetrically (not shown in the figure). Figure 3 As shown, it can also be formed by a wavy line that is rotated and then translated, that is, the measurement pattern 40 is arranged in a centrally symmetrical manner.

[0044] For example Figure 4As shown, the equally spaced arrangement can be a spiral line, and the spacing between adjacent circles is equal, and the width of each circle of lines is equal. Of course, the equally spaced arrangement, the equal-proportional arrangement or the periodic arrangement can also include graphics of other shapes, which are not repeated here. The graphics formed by the circuit graphics in the main circuit diagram area of ​​the wafer are periodic arrangements, equally spaced arrangements or equal-proportional arrangements. At this time, the critical dimension (CD) of the test pattern to be measured is the spacing between adjacent lines and the width of each line. Based on this, the measurement pattern 40 can be designed as a periodic arrangement, an equally spaced arrangement or an equal-proportional arrangement, so that the test pattern formed on the wafer cutting path is a periodic arrangement, an equally spaced arrangement or an equal-proportional arrangement.

[0045] See also Figure 2 , Figure 3 or Figure 4 Specifically, when the measurement pattern 40 on the mask 10 is designed to be periodically arranged, equally spaced, or proportionally arranged, based on the shape of the circuit pattern, the specific shape of the measurement pattern 40 can be designed to be periodically arranged, equally spaced, or proportionally arranged.

[0046] See also Figure 2 It should be noted that each annular line can be a continuous annular line or a annular line formed by multiple line segments, and there can be spacing between the multiple line segments. The critical dimension (CD) of the test pattern formed by the measurement pattern 40 on the photoresist on the wafer surface is the line spacing and the line width. The critical dimension (CD) of the pattern formed in the main circuit diagram area can be obtained according to the corresponding ratio.

[0047] See also Figure 4 When the specific shape of the measurement pattern 40 is designed as a spiral line or other similar shapes, it can be specifically designed based on the shape of the curve line pattern formed in the main circuit diagram area. The spiral line can be a continuous spiral line, or a spiral line formed by multiple arc line segments, and there can be spacing between the multiple arc line segments. The critical dimension (CD) of the measurement pattern formed by the measurement pattern 40 on the photoresist on the wafer surface can include line spacing and line width, and the critical dimension (CD) of the curve line pattern formed in the main circuit diagram area can be obtained according to the corresponding ratio.

[0048] See also Figure 5 and Figure 6 The shape of the straight line is similar to that of the spiral line. The size of the trajectory of the straight line increases clockwise or counterclockwise. The two adjacent circles of the straight line are arranged at equal intervals or in equal proportions. Figure 5 The straight lines in the figure are similar to the shape of an "S". Figure 6 The straight lines in Figure 5Based on the above, rotate the lines at both ends clockwise or counterclockwise to simulate a spiral shape.

[0049] See also Figure 7 In the photolithography process, when the pattern density difference between the measurement pattern 40 and the circuit pattern in the mask 10 is large, the pattern density difference between the main circuit pattern formed on the photoresist of the wafer and the measurement pattern will be large. The difference in pattern density will cause a deviation between the actual critical dimension (CD) and the measured critical dimension (CD) after the subsequent process. Based on this, since the device pattern area 20 corresponds to the main circuit pattern area of ​​the wafer, the pattern therein is dense. The pattern of the cutting road pattern area 30 is sparse. Therefore, this cutting road pattern area 30 can be designed with a redundant pattern 50, and the redundant pattern 50 can be set in the surrounding area of ​​the measurement pattern 40 to increase the pattern density of the cutting road pattern area where the redundant pattern 50 and the measurement pattern 40 are located, so that the difference between the pattern density of the area where the redundant pattern 50 and the measurement pattern 40 are located and the pattern density of the device pattern area is reduced, thereby improving the uniformity of the pattern density distribution.

[0050] Specifically, the specific structure of the redundant pattern 50 can be any polygonal line, circular line, straight line, broken line or other graphics. The number, size and spacing width of the redundant patterns 50 can be determined according to the pattern density distribution of the mask 10. For example, when the difference between the pattern area ratio of the cutting road pattern area and the pattern area ratio of the device pattern area in the mask 10 is large, the number of redundant patterns 50 can be increased, or the spacing between the redundant patterns 50 can be reduced, or the size of the redundant patterns 50 can be increased. In this way, by filling the redundant patterns 50, the overall difference in pattern density can be significantly reduced, thereby improving the measurement accuracy of the critical dimension (CD).

[0051] For the mask plate 10 provided by the utility model, based on the curved figure on the mask plate 10, a measurement figure with the same shape can be formed on the cutting path of the wafer. By measuring the critical dimension (CD) of the measurement figure, the critical dimension (CD) of the curved line on the main circuit diagram can be measured, thereby reducing the adverse effects on the photoresist when directly measuring the main circuit diagram, and significantly improving the measurement accuracy of the critical dimension (CD).

[0052] The utility model also provides a cutting path structure of a wafer, which can include a cutting path body and a test pattern. In the photolithography process, after the circuit pattern on the mask 10 and the measurement pattern 40 are subjected to the same photolithography operation, a pattern can be formed on the photoresist in the main circuit diagram area of ​​the wafer, and a test pattern similar to the measurement pattern 40 can be formed on the photoresist of the cutting path body of the wafer. At this time, by measuring the critical dimension (CD) of the test pattern, the critical dimension (CD) of the pattern on the main circuit diagram can be obtained according to the corresponding ratio. Thereby, the adverse effect on the photoresist on the main circuit diagram during measurement is significantly reduced, thereby improving the measurement accuracy of the critical dimension (CD).

[0053] See also Figure 7 Specifically, when the density difference between the main circuit pattern in the main circuit pattern area on the wafer surface and the test pattern on the main body of the cutting lane is large, a redundant pattern 50 can be designed on the mask 10. The redundant pattern 50 is projected onto the main body of the cutting lane of the wafer through photolithography, and the pattern density on the main body of the cutting lane is increased, so that the pattern density difference between the main body of the cutting lane and the main circuit pattern area is greatly reduced, and the uniformity of the pattern density distribution is improved, thereby improving the measurement accuracy of the critical dimension (CD).

[0054] In summary, the utility model provides a mask plate and a wafer cutting path structure. Based on the curve pattern on the mask plate, a measurement pattern with the same shape can be formed on the wafer cutting path. By measuring the critical dimension (CD) of the measurement pattern, the critical dimension (CD) of the curve line on the main circuit diagram can be measured, thereby avoiding adverse effects on the photoresist on the main circuit diagram and significantly improving the measurement accuracy of the critical dimension (CD). The unexpected effect is that the mask plate is also filled with redundant patterns, and a measurement pattern with the same shape can be formed on the wafer cutting path, which can reduce the difference between the pattern density on the wafer cutting path and the pattern density on the main circuit diagram, and significantly improve the measurement accuracy of the critical dimension (CD).

[0055] The embodiments of the utility model disclosed above are only used to help illustrate the utility model. The embodiments do not describe all the details in detail, nor do they limit the utility model to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the utility model, so that technicians in the relevant technical field can well understand and use the utility model. The utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A mask, characterized in that: include: A device pattern area, wherein a circuit pattern is arranged in the device pattern area; A cutting path pattern area, wherein the cutting path pattern area surrounds the device pattern area and is provided with a measurement pattern; The measurement pattern and the circuit pattern have the same shape, and are arranged in equal proportion to each other.

2. A mask according to claim 1, characterized in that: The circuit pattern and the measurement pattern are arranged periodically, at equal intervals or in equal proportions.

3. A mask according to claim 2, characterized in that: The measurement graph includes a plurality of curved lines, a plurality of straight lines and / or a plurality of broken lines; The measurement graph is formed by arranging a plurality of the curved lines, a plurality of the straight lines or a plurality of the broken lines separately; Alternatively, the measurement pattern is formed by combining and arranging a plurality of the curved lines, a plurality of the straight lines and a plurality of the broken lines.

4. A mask according to claim 3, characterized in that: The shape of the curved line or the broken line is a ring line, and a plurality of the ring lines are arranged at the same center.

5. A mask according to claim 3, characterized in that: In the measurement graph, the arrangement of multiple curved lines, multiple straight lines and / or multiple broken lines is formed by translating one of the lines, or the arrangement of multiple curved lines, multiple straight lines and / or multiple broken lines is formed by rotating one of the lines and then translating it.

6. A mask according to claim 3, characterized in that: The curved line includes at least one of a circular line, a wavy line, an arc line, a U-shaped line, a C-shaped line or an S-shaped line.

7. A mask according to claim 3, characterized in that: The shape of the curved line is a spiral line, in which two adjacent circles of lines are arranged at equal intervals or in equal proportions.

8. The mask according to claim 3, characterized in that: The shape of the straight line is similar to a spiral line, the track size of the straight line increases in a clockwise or counterclockwise direction, and two adjacent circles of the straight line are arranged at equal intervals or in equal proportions.

9. The mask according to claim 1, characterized in that: The cutting path pattern area further includes a redundant pattern, and the redundant pattern is arranged on one side of the measurement pattern.

10. A wafer sawing road structure, characterized in that: Using the mask according to any one of claims 1 to 9, the cutting road structure comprises: a cutting road body, wherein the cutting road body corresponds to a cutting road pattern area of ​​the mask; and A test pattern is arranged on the cutting path body, and the test pattern is a scaled pattern of the measurement pattern on the mask.

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