Photomask marking difference measuring device
By adding fillers to the photomask annotation measurement device to block the density difference area around the measurement device, the impact of the density change of the measurement part on the annotation difference measurement is solved, and the photomask annotation difference is improved measurement accuracy.
Patent Information
- Application Number
- CN202420975064.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-07
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-05-07
AI Technical Summary
In the existing photomask annotation measurement device, the density around the measurement piece changes dramatically, resulting in inaccurate annotation measurement results, affecting the yield of chip manufacturing.
Add fillers around the measuring part, which is located between the density difference area and the measuring part, blocking the density difference area to reduce the impact of density changes on the measurement.
The uniform filler reduces the density unevenness of the surrounding area of the measuring part, improves the measurement accuracy of the photomask annotation difference, and makes the measurement results more in line with the actual situation.
Smart Images
Figure CN222259834U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of photomask application devices, and in particular to a photomask marking difference measurement device. Background Art
[0002] With the development of semiconductor technology, the requirements for the registration difference accuracy of photomasks are also increasing. The manufacturing of high-end chips requires the participation of multiple high-end photomasks. The registration difference is related to the accuracy of the overlay of different layers of photomasks and is an important parameter of high-end photomasks. The manufacturing of chips requires the participation of multiple photomasks. Poor registration difference accuracy will affect the accuracy of the graphics on different photomasks when overlaying, thereby reducing the yield of chip production.
[0003] At present, the photomask annotation difference measurement device is Figure 1 As shown, the marking difference measurement device for the photomask includes a substrate 1 and a measuring piece 2 on the substrate 1; the substrate 1 with the measuring piece 2 is inserted into the photomask to be measured, and the regional density around the measuring piece 2 inserted into the photomask to be measured may vary greatly. There are both high-density areas 5 and low-density areas 4 around part of the measuring piece 2, which makes the regional density around the measuring piece 2 change more dramatically. The density change has a greater impact on the measurement of the marking difference measurement device.
[0004] Based on this, a new technical solution is needed. Utility Model Content
[0005] In view of this, an embodiment of the present disclosure provides a photomask marking difference measurement device.
[0006] The embodiments of this specification provide the following technical solutions:
[0007] The embodiment of the present specification provides a photomask annotation difference measurement device, including a substrate, a measurement component and a filling component;
[0008] The measuring piece and the filling piece are arranged on the base, and the filling piece is arranged around the outside of the measuring piece, and is configured such that the measuring device is used to be arranged on a photomask to be measured;
[0009] There is a density difference area around the measurement piece of the photomask to be measured, and the filling piece is located between the density difference area and the measurement piece, and is configured such that the filling piece is used to block the density difference area and the measurement piece.
[0010] Preferably, the density of the filling member is uniform.
[0011] Preferably, the area ratio of the filling area to the blank area of the filling piece is 1:1 to 1:10, and the filling piece is configured to meet the density requirement.
[0012] Preferably, the area ratio of the filling area to the blank area of the filling member is 1:5.
[0013] Preferably, the shape of the filling member includes a closed shape and is configured to completely surround the measuring member.
[0014] Preferably, the shape of the filling member is in a checkerboard pattern.
[0015] Preferably, the shape of the filling member is in a double-square shape.
[0016] Preferably, the central position of the filling member coincides with the central position of the measuring member.
[0017] Preferably, the density difference region includes a low-density region and a high-density region;
[0018] The density difference between the low-density region and the high-density region exceeds 30%.
[0019] Preferably, the size of the filling member is smaller than the minimum exposure size of the exposure machine.
[0020] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above technical solutions adopted in the embodiments of the present specification at least include:
[0021] In this application, a filling member is added around the measuring member, and the photomask measuring device is arranged on the photomask to be measured. The filling member is located between the measuring member and the density difference region, reducing the density non-uniformity in the region around the measuring member, reducing the influence of density changes on the annotation difference measuring device, making the measurement result more in line with the actual situation of the photomask to be measured, and improving the measurement accuracy of the photomask annotation difference. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.
[0023] Figure 1 is a schematic diagram of the low-density region and the high-density region around the measuring member on the photomask in the prior art;
[0024] Figure 2 is a schematic diagram of adding a first filling member around the measuring member in the present application;
[0025] Figure 3 is a schematic diagram of adding a second filling member around the measuring member in the present application.
[0026] Figure numerals: 1, substrate; 2, measuring piece; 3, filling piece; 4, low-density area; 5, high-density area. DETAILED DESCRIPTION
[0027] The embodiments of the present application are described in detail below with reference to the accompanying drawings.
[0028] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.
[0029] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.
[0030] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.
[0031] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the examples can be practiced without these specific details.
[0032] In view of this, the applicant has conducted in-depth research and improvement exploration on the photomask annotation difference and the measurement of the photomask annotation difference, and found that there are currently many ways to improve the photomask annotation difference, such as using a more accurate exposure machine. Alternatively, the GMC correction function of the exposure machine is used to correct the photomask graphic coordinates to the design coordinates. GMC (Grid Matching Correction) refers to the distortion of the photomask graphic due to the error caused by the photomask's own gravity and the stage system during the exposure process. The correction coefficient is calculated by measuring the degree of deviation of the graphic position, and the photomask graphic can be corrected to the design coordinates using the correction coefficient. GMC includes size correction, orthogonality correction, and high-order polynomial correction. Alternatively, the CEC correction function of the exposure machine is used to correct the photomask graphic coordinates to the design coordinates. CEC refers to the positive or negative charge on the exposed area of the photomask during the exposure process, which will produce an attractive or repulsive force on the electron beam, thereby causing the position of the electron beam to shift. However, there is still residual error after improvement using the above-mentioned improvement method.
[0033] The density of the pattern area around the photomask's annotation difference measurement device is different from the density of the actual main pattern, which will cause new errors on the original residual, making the measured annotation difference unable to reflect the actual condition of the photomask. Figure 1 As shown, the density variation around the measuring piece 2 is diverse. The measuring piece 2 used to measure the annotation difference on the photomask is located at the edge of the main pattern of the photomask. There are high-density areas 5 and low-density areas 4 around some of the measuring pieces 2, which leads to huge differences in the distribution of the pattern density around the measuring piece 2, so that new errors will be introduced in the measurement process of the annotation difference, making it difficult for the measurement results to reflect the real error of the photomask to be measured, affecting the accuracy of the annotation difference of the photomask, thereby reducing the production yield of the chip. Among them, the low-density area 4 and the high-density area 5 are relative. In extreme cases, it can be a comparison between a completely blank area 0 and a completely exposed area 100%. Generally speaking, if the density difference between the low-density area 4 and the high-density area 5 exceeds 30%, measurement errors may be introduced.
[0034] Based on this, the technical solutions provided by the embodiments of the present application are described below in conjunction with the accompanying drawings.
[0035] The embodiment of this specification provides a photomask annotation difference measurement device, such as Figure 2 and Figure 3As shown, it includes a substrate 1, a measuring component 2, and a filling component 3. The measuring component 2 and the filling component 3 are arranged on the substrate 1, and the filling component 3 is arranged around the outside of the measuring component 2 and is configured such that this measuring device is used to be arranged on a photomask to be measured. The substrate 1 can also serve as a carrier for the measuring component 2 and the filling component 3 respectively to form a measuring part and a filling part. The measuring component 2 and the filling component 3 can be fixed on the substrate 1. This measuring device can be inserted into the photomask to be measured. The measuring component 2 can be a measuring pattern or a measuring solid part. The filling component 3 can also be a filling pattern or a filling solid part. The substrate 1 can be a plate-shaped substrate 1 or a sheet-shaped substrate 1, etc. The measuring pattern and the filling pattern can be exposure patterns, and the measuring solid part and the filling solid part can be set on the substrate 1 by fixing methods such as pasting separately or integrally forming separately, etc.
[0036] There is a density difference area around the measuring component 2 arranged on the photomask to be measured, and the filling component 3 is located between the density difference area and the measuring component 2 and is configured such that the filling component 3 is used to block the density difference area and the measuring component 2.
[0037] The filling component 3 is filled around the measuring component 2 with a difference in notations and can be exposed and manufactured as a whole. According to the exposure limit, the size, area, and density of the filling component 3 that do not exceed the size of this measuring device, the unevenness of the density of the surrounding patterns is reduced. The filling component 3 is used to block the measuring component 2 to a certain extent from the uneven environment, reducing the negative impact of the surrounding environment on it. Therefore, the measurement result can more reflect the exposure error in the true situation at this position. In order to eliminate the possible measurement errors introduced.
[0038] In one embodiment, the density of the filling component 3 is uniform.
[0039] In one embodiment, the area ratio of the filling area to the blank area of the filling component 3 is from 1:1 to 1:10 and is configured such that the filling component 3 meets the density requirements. The filling area is, for example, the exposure area. If it is less than 1:1, the exposure risk will increase, and if it is greater than 1:10, it will be too sparse and the effect will be minimal.
[0040] In one embodiment, the area ratio of the filling area to the blank area of the filling component 3 is 1:5.
[0041] In one embodiment, the shape of the filling component 3 includes a closed shape and is configured to completely surround the measuring component 2. The filling component 3 can be a closed ring shape, that is, it is arranged completely around the measuring component 2. The shape of the filling component 3 is not unique and is a component with uniform density, keeping the density area consistent. The size of the filling component 3 is smaller than the limit size of the exposure machine to ensure that no actual pattern is exposed.
[0042] In one embodiment, the shape of the filling component 3 is in a checkerboard pattern.
[0043] In one embodiment, the shape of the filling component 3 is in a shape like a double square frame.
[0044] In one embodiment, the center position of the filling member 3 is consistent with the center position of the measuring member 2 .
[0045] In one embodiment, the density difference area includes a low-density area 4 and a high-density area 5; the density difference between the low-density area 4 and the high-density area 5 is greater than 30%.
[0046] In one embodiment, the size of the filler 3 is smaller than the minimum exposure size of the exposure machine. The size of the filler 3 is smaller than the limit size of the exposure machine. This makes it so that no actual pattern is produced on the mask product, thereby not affecting the subsequent use of the mask. The limit size of the exposure machine refers to the limit minimum size that can be achieved by exposure.
[0047] The present application adds a filler 3 of suitable density around the photomask, fills around the measuring piece 2, slows down the non-uniformity of the pattern density in the surrounding area, reduces the impact of the drastic change of the pattern density on the measuring piece 2, and is used to improve the precision error of the photomask when measuring the annotation difference. A filler 3 of suitable density is added around the measuring piece 2 on the photomask, which reduces the non-uniformity of the surrounding pattern density and reduces the impact of the density change on the annotation difference measurement device, so that the measurement result is more in line with the actual situation of the photomask.
[0048] In this specification, the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the embodiments described later, the description is relatively simple, and the relevant parts can be referred to the partial description of the previous embodiments.
[0049] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.
Claims
1. A photomask marking difference measurement device, characterized in that: It includes a substrate (1), a measuring element (2), and a filling element (3); The measuring element (2) and the filling element (3) are arranged on the substrate (1), and the filling element (3) is arranged around the outside of the measuring element (2), and is configured such that this measuring device is used to be arranged on a photomask to be measured; There is a density difference region around the measuring element (2) arranged on the photomask to be measured, and the filling element (3) is located between the density difference region and the measuring element (2), and is configured such that the filling element (3) is used to block the density difference region and the measuring element (2).
2. The photomask marking difference measurement device according to claim 1, characterized in that: The density of the filling element (3) is uniform.
3. The photomask marking difference measurement device according to claim 2, characterized in that: The area ratio of the filling region to the blank region of the filling element (3) is from 1:1 to 1:10, and is configured such that the filling element (3) meets the density requirement.
4. The photomask marking difference measurement device according to claim 3, characterized in that: The area ratio of the filling region to the blank region of the filling element (3) is 1:
5.
5. The photomask marking difference measurement device according to claim 1, characterized in that: The shape of the filling element (3) includes a closed shape, and is configured to completely surround the measuring element (2).
6. The photomask marking difference measurement device according to claim 5, characterized in that: The shape of the filling element (3) is in a checkerboard pattern.
7. The photomask marking difference measurement device according to claim 5, characterized in that: The shape of the filling element (3) is in a square-within-a-square shape.
8. The photomask marking difference measurement device according to claim 1, characterized in that: The center position of the filling element (3) coincides with the center position of the measuring element (2).
9. The photomask marking difference measurement device according to claim 1, characterized in that: The density difference region includes a low-density region (4) and a high-density region (5); The density difference between the low-density region (4) and the high-density region (5) exceeds 30%.
10. The photomask marking difference measurement device according to claim 1, characterized in that: The size of the filling element (3) is smaller than the minimum exposure size of the exposure machine.