Standard sheet and manufacturing method thereof, and method for testing defect grabbing capability of inspection machine

Abstract

The invention provides a standard sheet and a manufacturing method thereof, and a method for testing defect grabbing capability of an inspection machine, and belongs to the field of semiconductors. The standard sheet comprises a substrate, the substrate comprises a full-light-transmitting area and a semi-light-transmitting area, the full-light-transmitting area and the semi-light-transmitting area are both provided with a plurality of defects, and the defects comprise pinhole defects in various shapes. According to the invention, the full-light-transmitting area and the semi-light-transmitting area are arranged, and the defects comprise pinhole defects in various shapes, so that the pinhole defects in different shapes and pinhole defects on the surfaces of materials with different penetration rates can be grabbed and verified, and the defect grabbing capability of the machine table is verified and inspected. All-transparent and semi-transparent pinhole type defect standard sheets with different shapes are designed to verify the capability of low-end inspection equipment for grabbing pinhole type defects, so that more high-end inspection equipment can be saved to inspect graphic areas.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a standard sheet and a manufacturing method thereof, and a method for testing the defect-grabbing capability of an inspection machine. Background Art

[0002] The defect inspection of the photomask, also known as the phase-shift photomask (PSM), has pinhole-type defect capture requirements for the pure black area (MBBarea) around the graphic area, and the minimum size of the pinhole defect is ≤500nm. However, the design of the pinhole defects in the existing standard wafers has the following two problems, and these two problems will affect the verification of the pinhole defect capture capability of the inspection machine. Problem 1: There is only a circular design for pinhole defects in the standard wafer. In fact, various shapes of pinhole defects will be formed in the production process. The defect design of a single circular pinhole cannot fully meet the pinhole defect capture verification requirements of the actual product. Problem 2: There is only a fully transparent design for pinhole defects in the standard wafer. In the actual production process, some etching defects will be formed. The fully transparent pinhole defect design cannot fully meet the pinhole defect capture verification requirements of the actual product.

[0003] The above two problems have little impact on high-end inspection equipment (such as inspection equipment with laser light source), because the detection accuracy of high-end equipment is high ≤200nm, and the specification of the minimum size of pinhole defects ≤500nm fully meets the requirements. However, for some low-end inspection equipment, such as mercury lamp (Lamp) type light source inspection equipment, due to the relatively low inspection accuracy (minimum size ~ 500nm), the capture rate of pinhole defects of different shapes and penetration types is relatively challenging near the specification of ≤500nm.

[0004] It should be noted that the information disclosed in the background technology section of the invention is only intended to deepen the understanding of the general background technology of the invention, and should not be regarded as an admission or suggestion in any form that the information constitutes prior art already known to those skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a standard sheet and a method for making the standard sheet and a method for testing the defect capture capability of an inspection machine, so as to solve the problem that low-end inspection equipment with low detection accuracy has a low capture rate for pinhole defects of different shapes and penetration types.

[0006] In order to solve the above technical problems, the present invention provides a standard sheet for testing the defect-grabbing capability of an inspection machine, comprising:

[0007] The substrate comprises a fully light-transmitting area and a semi-light-transmitting area, wherein the fully light-transmitting area and the semi-light-transmitting area are both provided with a plurality of defects, wherein the defects comprise pinhole defects of various shapes.

[0008] Preferably, the substrate comprises a glass substrate, a molybdenum silicide material layer deposited on the surface of the glass substrate, and metal chromium deposited on the surface of the molybdenum silicide material layer, wherein the glass substrate is a fully light-transmitting material, the molybdenum silicide material layer is a semi-light-transmitting material, defects in the fully light-transmitting area penetrate the molybdenum silicide material layer and expose the glass substrate, and defects in the semi-light-transmitting area penetrate the metal chromium and expose the molybdenum silicide material layer.

[0009] Preferably, a plurality of the defects are arranged in a stepped manner in the first direction according to the sizes of the defects, and a plurality of the defects are distributed in the second direction according to the shapes of the defects.

[0010] Preferably, the defect is an irregular shape, and a plurality of the irregular shapes are arranged in order from large to small in size.

[0011] Preferably, the shape of the defect includes one of circular, square, ring, triangle, hexagon, octagon or any combination thereof.

[0012] Based on the same inventive concept, the present invention also provides a method for making the standard sheet as described above, comprising:

[0013] Providing a substrate, and selecting a fully light-transmitting area and a semi-light-transmitting area in the substrate;

[0014] A number of defects are made in the fully light-transmitting area and the semi-light-transmitting area, and the defects include pinhole defects of various shapes, including the above-mentioned standard film.

[0015] Preferably, the substrate comprises a glass substrate, a molybdenum silicide material layer deposited on the surface of the glass substrate, and metal chromium deposited on the surface of the molybdenum silicide material layer, wherein the glass substrate is a fully light-transmitting material, the molybdenum silicide material layer is a semi-light-transmitting material, defects in the fully light-transmitting area penetrate the molybdenum silicide material layer and expose the glass substrate, and defects in the semi-light-transmitting area penetrate the metal chromium and expose the molybdenum silicide material layer.

[0016] Preferably, a plurality of the defects are arranged in a stepped manner in the first direction according to the sizes of the defects, and a plurality of the defects are distributed in the second direction according to the shapes of the defects.

[0017] Based on the same inventive concept, the present invention also provides a method for making the standard sheet as described above, comprising:

[0018] Providing a standard sheet as described above;

[0019] The standard pieces are inspected using a testing machine, and the defect grabbing capability is tested in descending order of size.

[0020] Compared with the prior art, the standard sheet of the present invention has the following advantages:

[0021] The present invention sets a fully transparent area and a semi-transparent area, and the fully transparent area and the semi-transparent area are both provided with a number of defects, including pinhole defects of various shapes, so as to verify the capture of pinhole defects of different shapes and pinhole defects on the surface of materials with different penetration rates, so as to verify the defect capture capability of the inspection machine. The standard film of fully transparent and semi-transparent pinhole defects of different shapes is designed to verify the capture capability of low-end inspection equipment for pinhole defects, so as to save more high-end inspection equipment for inspection of graphic areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of a pinhole defect in one embodiment;

[0023] Figure 2 is a schematic diagram of the distribution structure of the pattern area and the pure black area in the photomask in one embodiment of the present invention;

[0024] Figure 3 is a schematic structural diagram of various pinhole defect shapes in one embodiment of the present invention;

[0025] Figure 4 is a schematic structural diagram of a pinhole defect in a fully light-transmitting area in one embodiment of the present invention;

[0026] Figure 5 is a schematic structural diagram of a pinhole defect in a semi-transparent area in one embodiment of the present invention;

[0027] Figure 6 is a schematic structural diagram of setting a pinhole defect on a photomask in one embodiment of the present invention;

[0028] Figure 7 is a schematic diagram of a structure in which a defect is formed in a pure black area in one embodiment of the present invention;

[0029] In the figure,

[0030] 10-circular defect; 20-sample;

[0031] 100-glass substrate; 200-molybdenum silicide material layer;

[0032] 300-metal chromium layer; 400-defect;

[0033] 500-wafer. DETAILED DESCRIPTION

[0034] In order to make the purpose, advantages and features of the present invention clearer, the standard sheet and its manufacturing method, and the method for testing the defect-grabbing ability of the inspection machine proposed in the present invention are further described in detail below in combination with the drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. It should be understood that the drawings in the specification do not necessarily show the specific structure of the present invention in proportion, and the illustrative features used to illustrate certain principles of the present invention in the drawings in the specification will also adopt a slightly simplified drawing method. The specific design features of the present invention disclosed herein include, for example, specific dimensions, directions, positions and shapes, which will be determined in part by the specific application and use environment. And, in the embodiments described below, sometimes the same figure mark is used in common between different drawings to represent the same part or a part with the same function, and its repeated description is omitted. In this specification, similar numbers and letters are used to represent similar items, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0036] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0037] Ginseng Figure 1 and Figure 2 As shown, Figure 1 Schematic diagram of the structure of a pinhole defect in one embodiment. Figure 2 1 is a schematic diagram of the distribution structure of the pattern area and the pure black area in the photomask in one embodiment of the present invention. That is, only one shape of pinhole defect, the circular defect 10, is formed on the sample 20. However, in actual product production, pinhole defects of various shapes will be generated. In addition, Figure 1 In the sample 20, there are only pinhole defects with a fully light-transmitting design, while in actual product production, there are pinhole defects with fully light-transmitting and semi-light-transmitting designs. Therefore, the existing sample 20 cannot meet the needs of actual product pinhole defect capture and verification. Especially for the verification of the capture capability of a detection machine with a detection accuracy of 500nm. The photomask is made of molybdenum silicide in the graphic area, and the pure black area is made of metallic chromium. The detection of the pure black area only has requirements for pinhole defects. If the pure black area is inspected together with the graphic area, the production capacity of high-end inspection equipment will be wasted. Some existing low-end inspection equipment (such as inspection equipment with lamp-type light sources) cannot inspect defects in the graphic area, but can cover part of the production capacity for the pure black area. However, low-end inspection equipment faces great challenges in capturing pinhole defects of different shapes and partially translucent when conducting inspections. Therefore, standard films of pinhole defects of different shapes that are fully translucent and semi-translucent are designed to verify the ability of low-end inspection equipment to capture pinhole defects, thereby saving more high-end inspection equipment for inspecting the graphic area.

[0038] The core idea of ​​the present invention is to provide a standard sheet that can verify the capture of pinhole defects of different shapes and pinhole defects on the surface of materials with different penetration rates, so as to verify the defect capture capability of the inspection machine.

[0039] In order to realize the above idea, the present invention provides a standard sheet, Figures 3 to 7 A specific implementation of a standard film disclosed. The standard film includes a substrate, the substrate includes a fully transparent area and a semi-transparent area, the graphic area and the opaque area are both provided with a plurality of defects, and the defects include pinhole defects of various shapes.

[0040] Exemplarily, the substrate includes a glass substrate 100, a molybdenum silicide material layer 200 deposited on the surface of the glass substrate, and a metal chromium layer 300 deposited on the surface of the molybdenum silicide material layer 200, wherein the glass substrate 100 is a fully light-transmitting material, the molybdenum silicide material layer 200 is a semi-light-transmitting material, and the defects in the fully light-transmitting area penetrate the molybdenum silicide material layer 200 and expose the glass substrate 100. The defects 400 in the opaque area penetrate the metal chromium layer 300 and expose the molybdenum silicide material layer 200.

[0041] Specifically, refer to Figure 4 and Figure 5As shown, the glass substrate 100 is a substrate made of glass material, and the light transmittance of the glass substrate 100 is 100%, so it is a transparent material. The light transmittance of the molybdenum silicide material layer 200 is 6%, so the molybdenum silicide material layer 200 is a semi-transparent material. The light transmittance of the metal chromium layer 300 is 0%, so the metal chromium is an opaque material. The area where the glass substrate 100 is exposed is positioned as a light-transmitting area. The area where the molybdenum silicide material layer 200 is exposed is positioned as a semi-transparent area. In this embodiment, a defect 400 is formed in the light-transmitting area of ​​the standard film. A defect 400 is also formed in the semi-transparent area. Therefore, when the standard film in this embodiment is used to detect the grasping ability of the inspection machine, the requirements of pinhole-type defects 400 with both full light transmission and semi-light transmission can be met.

[0042] Exemplarily, the plurality of defects 400 are arranged in a first direction (ie, Figure 6 The defects are arranged in a step-by-step manner according to the size of the defects. Figure 6 The X direction in the figure) is distributed according to the shape of the defect.

[0043] Specifically, refer to Figures 3 to 6 As shown, the size of the defect is 0.1μm to 2μm. The distance between two adjacent defects is 200μm. Pinhole defects of various shapes include one of circular, square, annular, triangular, hexagonal, octagonal or any combination thereof. The defect can also be an irregular shape, and several of the irregular shapes are arranged in order from large to small in size. The size d of the defect can be 2μm, 0.1μm, or any value in the range of 0.1μm to 2μm. In this embodiment, the size of each defect 400 is selected to be 2μm, 1.9μm, 1.8μm, 1.7μm, 1.6μm, 1.5μm, 1.4μm, 1.3μm, 1.2μm, 1.1μm, 1.0μm, 0.9μm, 0.8μm, 0.7μm, 0.6μm, 0.5μm, 0.4μm, 0.93m, 0.2μm, 0.1μm in a stepped arrangement. The spacing between two adjacent defects 400 is 200μm. Whether in the lateral direction or the longitudinal direction, the spacing between two adjacent defects 400 is 200μm. Among them, the diameter of the outer ring of the annular defect 400 is 0.1μm to 2μm, and the diameter of the inner ring is 0.05μm to 1μm. The size of two adjacent inner rings in each column differs by 50nm. The size difference between two adjacent defects in each column is 100nm.

[0044] The stepped arrangement of dimensions in the first direction can verify the limit of the inspection equipment's grasping ability and confirm the capabilities of different inspection equipment. The arrangement of shapes in the second direction can verify whether the changes in different shapes at each size have an impact on the inspection equipment's grasping ability. In addition, such two-directional arrangements are made in the fully transparent area and the semi-transparent area to more comprehensively simulate the actual defect morphology and more comprehensively evaluate the inspection equipment's grasping ability. By setting defects 400 of various shapes, the needs of grasping and verifying pinhole defects 400 of actual products can be met when verifying the inspection machine's grasping ability.

[0045] To realize the above idea, Figures 3 to 6 As shown, this embodiment also discloses a method for making the standard sheet as described above, including the following steps S11 and S12.

[0046] Step S11: providing a substrate, and selecting a semi-transparent area and a fully transparent area in the substrate.

[0047] Specifically, refer to Figures 3 to 6 As shown, a substrate is provided. The substrate is a photomask. The substrate includes a glass substrate 100, a molybdenum silicide material layer 200 deposited on the surface of the glass substrate 100, and a metal chromium layer 300 deposited on the surface of the molybdenum silicide material layer 200. A portion of the substrate is selected as a semi-transparent area, and another portion is selected as a fully transparent area, forming a structure as shown in Figure (6b).

[0048] Step S12: making a plurality of defects in the fully light-transmitting area and the semi-light-transmitting area, wherein the defects include pinhole defects of various shapes.

[0049] Specifically, refer to Figure 5 and Figure 6 As shown, the size of the designed defect 400 is 0.1um to 2um, each step is 0.1um, and the horizontal and vertical spacing of each defect is set to 200um. The defect design is converted into an exposure file, which includes the positioning reference points of the photomask and the pattern of the designed pinhole-type defect. Only the metal chromium layer 300 is etched in the semi-transparent area to form a defect 400 in the semi-transparent area, and the structure shown in Figure (6a) is formed after etching. After etching the metal chromium layer 300 in the fully transparent area, the molybdenum silicide material layer 200 is etched to form a defect 400 in the fully transparent area, and after etching according to the design requirements, the structure shown in Figure (6c) is formed.

[0050] To realize the above idea, Figures 3 to 7 As shown, this embodiment also discloses a method for testing the ability of a machine to grasp defects, including the following steps S21 and S22:

[0051] Step S21: providing a standard film.

[0052] Specifically, refer to Figures 3 to 6 As shown, the standard sheet has a semi-transparent area and a fully transparent area as described above, and pinhole-like defects 400 with different shapes are formed in the semi-transparent area and the fully transparent area. In addition, the defects 400 are designed according to the distribution shown in Figure (6a) and Figure (6c).

[0053] Step S22: using a testing machine to inspect the standard piece, and testing the defect capture capability in descending order of size.

[0054] Specifically, refer to Figure 6 and Figure 7 As shown, according to the designed defect coordinates, the defect specifications are measured to confirm the defect type and size exposed on the wafer 500. The inspection machine tests and debugs the standard film to ensure that it can be exposed to Figure 7 All pinhole defects 400 on the wafer 500 can be inspected.

[0055] By capturing defects of different sizes, types and shapes in the standard film, the limit ability and stability of the inspection machine in capturing defects can be tested. If the defects of the corresponding types, shapes and sizes can be captured in the above standard film, then they can also be captured in actual applications. Therefore, the inspection capability of the inspection machine can be more completely verified to ensure that the inspection machine can detect small defects on the photomask production pattern to meet the current process requirements.

[0056] In summary, the above embodiments provide detailed descriptions of different configurations of standard sheets and methods for making them, and methods for testing the defect-grabbing capabilities of inspection machines. Of course, the above descriptions are only descriptions of preferred embodiments of the present invention, and are not limitations on the scope of the present invention. The present invention includes but is not limited to the configurations listed in the above embodiments. Those skilled in the art can draw inferences based on the contents of the above embodiments. Any changes and modifications made by those of ordinary skill in the field of the present invention based on the above disclosures shall fall within the scope of protection of the claims.

Claims

1. A standard sheet for testing the defect-grabbing capability of an inspection machine, characterized in that: include: The substrate comprises a fully light-transmitting area and a semi-light-transmitting area, wherein the fully light-transmitting area and the semi-light-transmitting area are both provided with a plurality of defects, wherein the defects comprise pinhole defects of various shapes.

2. The standard sheet according to claim 1, characterized in that: The substrate includes a glass substrate, a molybdenum silicide material layer deposited on the surface of the glass substrate, and metal chromium deposited on the surface of the molybdenum silicide material layer, wherein the glass substrate is a fully light-transmitting material, the molybdenum silicide material layer is a semi-light-transmitting material, the defects in the fully light-transmitting area penetrate the molybdenum silicide material layer and expose the glass substrate, and the defects in the semi-light-transmitting area penetrate the metal chromium and expose the molybdenum silicide material layer.

3. The standard sheet according to claim 1, characterized in that: Some of the defects are arranged in a stepped manner in the first direction according to the sizes of the defects, and some of the defects are distributed in the second direction according to the shapes of the defects.

4. The standard sheet according to claim 3, characterized in that: The defects are irregular in shape, and a plurality of the irregular shapes are arranged in order from large to small in size.

5. The standard sheet according to claim 3, characterized in that: The shape of the defect includes one of circle, square, ring, triangle, hexagon, octagon or any combination thereof.

6. The standard sheet according to claim 1, characterized in that: The size of the defect is 0.1 μm to 2 μm.

7. A method for making a standard sheet as claimed in any one of claims 1 to 6, characterized in that: include: Providing a substrate, and selecting a fully light-transmitting area and a semi-light-transmitting area in the substrate; A plurality of defects are made in the fully light-transmitting area and the semi-light-transmitting area, and the defects include pinhole defects of various shapes.

8. The method for making a standard sheet according to claim 7, characterized in that: The substrate includes a glass substrate, a molybdenum silicide material layer deposited on the surface of the glass substrate, and metal chromium deposited on the surface of the molybdenum silicide material layer, wherein the glass substrate is a fully light-transmitting material, the molybdenum silicide material layer is a semi-light-transmitting material, the defects in the fully light-transmitting area penetrate the molybdenum silicide material layer and expose the glass substrate, and the defects in the semi-light-transmitting area penetrate the metal chromium and expose the molybdenum silicide material layer.

9. The method for making a standard sheet according to claim 7, characterized in that: Some of the defects are arranged in a stepped manner in the first direction according to the sizes of the defects, and some of the defects are distributed in the second direction according to the shapes of the defects.

10. A method for testing the defect-grabbing capability of an inspection machine, characterized in that: include: Providing a standard sheet as described in any one of claims 1-6; The standard pieces are inspected using a testing machine, and the defect grabbing capability is tested in descending order of size.

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