Calibration plate and preparation method and application thereof

Abstract

The invention discloses a calibration plate and a preparation method and application thereof, and relates to the technical field of calibration plates. The preparation method of the calibration plate comprises the following steps: S1, first double-sided rough grinding: carrying out first double-sided rough grinding on a substrate plate by using a grinding pad matched with a grinding liquid; s2, performing second double-sided rough grinding, namely performing second double-sided rough grinding on the base plate treated in the step S1 by using a grinding pad matched with polishing powder; s3, sequentially carrying out film coating treatment, gluing treatment, photoetching treatment and developing corrosion treatment on one surface of the base plate treated in the step S2; during film coating, the thickness of a film layer coated on the base plate is not less than 90 nm. The prepared calibration plate can accurately reflect the state of detection equipment.

Description

Technical Field

[0001] The invention relates to the technical field of calibration plates, and in particular to a calibration plate and a preparation method and application thereof. Background Art

[0002] The measurement accuracy of semiconductor testing equipment is a key indicator of the equipment. Usually, a homemade calibration plate is used for testing to achieve accurate mapping of the world coordinate system of the image midpoint to the camera coordinate system. In related technologies, different positions of the sample are restricted by a specific optical path system and are affected by multiple factors such as non-uniform illumination and image noise. Simple homemade calibration plates cannot accurately reflect the status of the testing equipment. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a method for preparing a calibration plate, wherein the prepared calibration plate can accurately reflect the state of its detection device.

[0004] The present invention also provides a calibration plate obtained by the above preparation method.

[0005] The present invention also provides application of the calibration plate in camera parameter calibration.

[0006] A method for preparing a calibration plate according to an embodiment of the first aspect of the present invention comprises the following steps: S1, first double-sided rough grinding: Performing a first double-sided rough grinding of the base plate using a grinding pad and a grinding liquid; S2, second double-sided rough grinding: Performing a second double-sided rough grinding of the base plate processed in step S1 using a grinding pad and polishing powder; S3, sequentially performing a coating process, a glue coating process, a photolithography process, and a development and etching process on one side of the substrate processed in step S2; During film coating, the thickness of the film layer coated on the substrate is not less than 90 nm.

[0007] The preparation method according to the embodiment of the present invention has at least the following beneficial effects: The calibration plate prepared by the preparation method of the embodiment can accurately reflect the state of its detection equipment, solves the problem of low point accuracy in the prior art, and avoids the influence of multiple factors such as non-uniform lighting and image noise, and has good application prospects in the field of camera parameter calibration.

[0008] The term "not less than" means greater than or equal to, and should be understood to include the number itself.

[0009] The term "not higher than" means less than or equal to, and should be understood to include the number itself.

[0010] According to some embodiments of the present invention, the base plate comprises a glass substrate.

[0011] According to some embodiments of the present invention, the grinding liquid is 10wt%~30wt%. 95 The corundum solution with a particle size of less than 10 μm can be, for example, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt%, 24wt%, 25wt%, 26wt%, 27wt%, 28wt%, 29wt% or 30wt%.

[0012] According to some embodiments of the present invention, the polishing powder is cerium oxide.

[0013] According to some embodiments of the present invention, after being processed in step S1, the PV value of the substrate is not higher than 10 μm.

[0014] According to some embodiments of the present invention, after the processing in step S1, the PV value of the substrate is 0.5 μm to 10 μm. For example, it can be 0.5 μm, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm or 10 μm.

[0015] According to some embodiments of the present invention, after being processed in step S2, the PV value of the substrate is not higher than 2 μm.

[0016] According to some embodiments of the present invention, after the processing in step S2, the PV value of the substrate is 0.1 μm to 2 μm. For example, it may be 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.7 μm, 1.8 μm, 1.9 μm or 2 μm.

[0017] According to some embodiments of the present invention, after the processing in step S2, the surface roughness Ra of the substrate is 0.02 nm to 0.8 nm. For example, it may be 0.02 nm, 0.04 nm, 0.06 nm, 0.08 nm, 0.1 nm, 0.15 nm, 0.2 nm, 0.25 nm, 0.3 nm, 0.35 nm, 0.4 nm, 0.45 nm, 0.5 nm, 0.55 nm, 0.6 nm, 0.65 nm, 0.7 nm, 0.75 nm or 0.8 nm.

[0018] According to some embodiments of the present invention, the coating process comprises the following steps: The one side of the substrate plate processed in step S2 is subjected to ultrasonic cleaning and DC magnetron sputtering in sequence to obtain a coated plate coated with a metal film.

[0019] According to some embodiments of the present invention, the vacuum degree of the DC magnetron sputtering process is (1-8) × 10 -6 For example, it can be 1×10 -6 , 1.5×10 -6 , 2×10 -6 , 2.5×10 -6 , 3×10 -6 , 3.5×10 -6 , 4×10 -6 , 4.5×10 -6 , 5×10 -6 , 5.5×10 -6 , 6×10 -6 , 6.5×10 -6 ,7×10 -6 , 7.5×10 -6 or 8×10 -6 .

[0020] According to some embodiments of the present invention, the sputtering power of the DC magnetron sputtering process is 0.5 kW to 2 kW. For example, it can be 0.5 kW, 0.6 kW, 0.7 kW, 0.8 kW, 0.9 kW, 1 kW, 1.1 kW, 1.2 kW, 1.3 kW, 1.4 kW, 1.5 kW, 1.6 kW, 1.7 kW, 1.8 kW, 1.9 kW or 2 kW.

[0021] According to some embodiments of the present invention, the process gas for the DC magnetron sputtering treatment is Ar\N2\O2\CO2 in a ratio of (25~45) sccm: (15~35) sccm: 0 sccm: (1~20) sccm.

[0022] According to some embodiments of the present invention, the process gas for the DC magnetron sputtering treatment is Ar\N2\O2\CO2 in a ratio of (30~40) sccm: (20~30) sccm: 0 sccm: (4~14) sccm.

[0023] According to some embodiments of the present invention, the film layer is a chromium film layer.

[0024] According to some embodiments of the present invention, the thickness of the film layer is 90 nm to 110 nm. For example, it may be 90 nm, 91 nm, 92 nm, 93 nm, 94 nm, 95 nm, 96 nm, 97 nm, 98 nm, 99 nm, 100 nm, 101 nm, 102 nm, 103 nm, 104 nm, 105 nm, 106 nm, 107 nm, 108 nm, 109 nm or 110 nm.

[0025] According to some embodiments of the present invention, the gluing process comprises the following steps: The photoresist is spin-coated on the plated substrate to obtain a composite plate with a photoresist film.

[0026] According to some embodiments of the present invention, the thickness of the photoresist film is 100 nm to 500 nm, for example, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm or 500 nm.

[0027] According to some embodiments of the present invention, the thickness of the photoresist film is 200 nm to 300 nm.

[0028] According to some embodiments of the present invention, the uniformity of the photoresist film reaches ±0.5% and the resolution reaches 1 μm.

[0029] According to some embodiments of the present invention, the photolithography process comprises the following steps: An imported photolithography machine with an I-line high-resolution lens is used for the exposure process, and lines can be made to 1 μm.

[0030] According to some embodiments of the present invention, the development and etching process comprises the following steps: After removing the exposed photoresist, the exposed plating layer is removed by etching.

[0031] According to some embodiments of the present invention, the removing of the exposed photoresist comprises: using 0.005% to 0.3% TMAH for treatment, the treatment time is 8 s to 12 s, and the treatment temperature is 20° C. to 25° C.

[0032] According to some embodiments of the present invention, the removing corrosion of the exposed plating layer includes: using a corrosive solution for treatment. The corrosive solution is ammonium cerium nitrate. The treatment time is 35 s to 45 s. The treatment temperature is 20° C. to 25° C.

[0033] The calibration plate according to the embodiment of the second aspect of the present invention is prepared by the preparation method described in the embodiment of the first aspect of the present invention.

[0034] According to some embodiments of the present invention, the calibration plate is divided into 13 levels of arrays, each level of the array is composed of 2*50 marking points, the spacing of each level of the array is 0.1 mm, and the position spacing error of the marking points is less than ±100 nm; the sizes of the marking points are 2000 nm, 1500 nm, 1200 nm, 1000 nm, 900 nm, 800 nm, 700 nm, 600 nm, 500nm, 400 nm, 300 nm, 200 nm, and 100 nm, respectively.

[0035] According to some embodiments of the present invention, the size of the calibration plate is 152 mm×152 mm. According to some embodiments of the present invention, the marking point is selected from a square, a solid circle, a ring or a cross.

[0036] According to some embodiments of the present invention, the accuracy of the distance between the geometric centers of adjacent marking points is within the range of ±0.02 mm.

[0037] According to a third aspect of the present invention, the calibration plate as described in the second aspect of the present invention is used in camera parameter calibration.

[0038] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a front schematic diagram of a high-precision array mask calibration plate according to Example 1 of the present invention; Figure 2 The image detection conditions of the high-precision array mask calibration plate of Example 1 and Comparative Example 1; Figure 3 The image detection results of the high-precision array mask calibration plate of Example 1 and Comparative Example 1. DETAILED DESCRIPTION

[0040] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0041] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0042] In the description of the present invention, if there is a description of first, second, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0043] When a numerical range is disclosed herein, the above range is considered to be continuous and includes the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0044] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0045] Example 1 This example provides a high-precision array mask calibration plate for precision inspection of semiconductor detection equipment. The calibration plate has an outer dimension of 152 mm×152 mm. Each level adopts a 2*50 array. The marking points are squares of corresponding sizes with a spacing of 0.1 mm. The point spacing error is less than ±100 nm. Each group has 13 levels of arrays, and the sizes are 2000nm, 1500nm, 1200nm, 1000nm, 900nm, 800nm, 700nm, 600nm, 500nm, 400nm, 300nm, 200nm, and 100nm respectively.

[0046] The front schematic diagram of the high-precision array mask calibration plate is shown in Figure 1 shown.

[0047] This example also provides a method for preparing the high-precision array mask calibration plate, the steps are as follows: S1, first double-sided rough grinding: Use polishing pad with polishing fluid (20wt% DN 95 The polishing sheet / original glass is subjected to the first double-sided rough grinding using a diamond abrasive suspension with a particle size of less than 10 μm. The PV value of the polishing sheet / original glass after the first double-sided rough grinding is 9 μm; S2, second double-sided rough grinding: The polished sheet / original glass treated in step S1 was subjected to a second double-sided rough grinding using a grinding pad and cerium oxide polishing powder (model SS-CE420, purchased from Hangzhou Jikang New Materials Co., Ltd.). After the second double-sided rough grinding, the PV value of the polished sheet / original glass was 1.5 μm, and the surface roughness Ra was 0.4 nm.

[0048] S3. Perform coating treatment, glue coating treatment, photolithography treatment, and development and corrosion treatment on one side of the polished sheet / original glass in sequence.

[0049] S31, coating treatment: The polished sheet / original glass processed in step S2 is ultrasonically cleaned, dried, and placed in a magnetron sputtering vacuum chamber, and a chromium film (film thickness 100 nm) is plated using a DC magnetron sputtering process to obtain a coated plate.

[0050] The parameters of the DC magnetron sputtering process are as follows: the ratio of process gases Ar\N2\O2\CO2 is 35 sccm: 25 sccm: 0 sccm: 9 sccm, and the vacuum degree is 4×10 -6 , and sputtering power 1.2 kw.

[0051] S32, Gluing treatment: The photoresist film with a thickness of 250 nm was obtained by spin coating, with a uniformity of ±0.5% and a resolution of 1 μm.

[0052] S33, photolithography processing: An imported photolithography machine with an I-line high-resolution lens is used for the exposure process, and lines can be made to 1 μm.

[0053] S34, development and corrosion treatment: After exposure, on a precise fully automatic development and etching device, at 23°C, the exposed photoresist was first reacted and removed with 0.01% TMAH for 10 s; then a special etching solution (ammonium cerium nitrate) was used to remove the chromium layer exposed after the development and removal of the photoresist, and the etching time was 40 s.

[0054] Comparative Example 1 This example is a high-precision array mask calibration plate, which is basically the same as Example 1, with the only difference being that the thickness of the chromium film plated in step S3 is 80 nm.

[0055] The dimensions of the high-precision array mask calibration plate are 152 mm×152 mm. Each level adopts a 2*50 array. The marking points are squares of corresponding sizes with a spacing of 0.1 mm. The point spacing error is less than ±100 nm. Each group has 13 levels of arrays, with sizes of 2000nm, 1500nm, 1200nm, 1000nm, 900nm, 800nm, 700nm, 600nm, 500nm, 400nm, 300nm, 200nm, and 100nm respectively.

[0056] The preparation method steps are as follows: S1, first double-sided rough grinding: Use polishing pad with polishing fluid (20wt% DN 95 The polishing sheet / original glass is subjected to the first double-sided rough grinding using a diamond abrasive suspension with a particle size of less than 10 μm. The PV value of the polishing sheet / original glass after the first double-sided rough grinding is 9 μm; S2, second double-sided rough grinding: The polished sheet / original glass treated in step S1 was subjected to a second double-sided rough grinding using a grinding pad and cerium oxide polishing powder (model SS-CE420, purchased from Hangzhou Jikang New Materials Co., Ltd.). After the second double-sided rough grinding, the PV value of the polished sheet / original glass was 1.5 μm, and the surface roughness Ra was 0.4 nm.

[0057] S3. Perform coating treatment, glue coating treatment, photolithography treatment, and development and corrosion treatment on one side of the polished sheet / original glass in sequence.

[0058] S31, coating treatment: The polished sheet / original glass processed in step S2 is ultrasonically cleaned, dried, and placed in a magnetron sputtering vacuum chamber, and a chromium film (film thickness 80 nm) is plated using a DC magnetron sputtering process to obtain a coated plate.

[0059] The parameters of the DC magnetron sputtering process are as follows: the ratio of process gases Ar\N2\O2\CO2 is 35 sccm: 25 sccm: 0 sccm: 9 sccm, and the vacuum degree is 4×10 -6 , and sputtering power 1.2 kw.

[0060] S32, Gluing treatment: The photoresist film with a thickness of 250 nm was obtained by spin coating, with a uniformity of ±0.5% and a resolution of 1 μm.

[0061] S33, photolithography processing: An imported photolithography machine with an I-line high-resolution lens is used for the exposure process, and lines can be made to 1 μm.

[0062] S34, development and corrosion treatment: After exposure, on a precise fully automatic development and etching device, at 23°C, the exposed photoresist was first reacted and removed with 0.01% TMAH for 10 s; then a special etching solution (ammonium cerium nitrate) was used to remove the chromium layer exposed after the development and removal of the photoresist, and the etching time was 40 s.

[0063] Test example The same image was detected by a detector using the high-precision array mask calibration plates of Example 1 and Comparative Example 1.

[0064] The results are as follows Figure 2~3 shown.

[0065] The detection rate of the calibration plate prepared in Example 1 is 100%, while that of Comparative Example 1 is only 80%; and the completeness of the detected image of Example 1 is also much higher than that of Comparative Example 1.

[0066] The embodiments of the present invention are described in detail above in conjunction with the embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A method for preparing a calibration plate, characterized in that: The following steps are involved: S1, first double-sided rough grinding: Performing a first double-sided rough grinding of the base plate using a grinding pad and a grinding liquid; S2, second double-sided rough grinding: Performing a second double-sided rough grinding of the base plate processed in step S1 using a grinding pad and polishing powder; S3, sequentially performing a coating process, a glue coating process, a photolithography process, and a development and etching process on one side of the substrate processed in step S2; During film coating, the thickness of the film layer coated on the substrate is not less than 90 nm.

2. The preparation method according to claim 1, characterized in that: After being processed in step S1, the PV value of the substrate is not higher than 10 μm.

3. The preparation method according to claim 1, characterized in that: After being processed in step S2, the PV value of the substrate is not higher than 2 μm; And / or, after being processed in step S2, the surface roughness Ra of the base plate is 0.02 nm~0.8 nm.

4. The preparation method according to claim 1, characterized in that: The coating process comprises the following steps: The one side of the substrate plate processed in step S2 is subjected to ultrasonic cleaning and DC magnetron sputtering in sequence to obtain a coated plate coated with a metal film.

5. The preparation method according to claim 1, characterized in that: The vacuum degree of the DC magnetron sputtering process is (1-8) × 10 -6 ; And / or, the sputtering power of the DC magnetron sputtering process is 0.5 kW to 2 kW; And / or, the process gas for the DC magnetron sputtering treatment is Ar\N2\O2\CO2 in a ratio of (25~45) sccm: (15~35) sccm: 0 sccm: (1~20) sccm.

6. The preparation method according to claim 1, characterized in that: The gluing process comprises the following steps: Spin coating photoresist on the plated substrate to obtain a composite plate with a photoresist film; And / or, the photolithography process comprises the following steps: An imported photolithography machine with an I-line high-resolution lens is used for exposure process, and lines can be made to 1 μm; And / or, the developing and etching process comprises the following steps: After removing the exposed photoresist, the exposed plating layer is removed by etching.

7. The preparation method according to claim 1, characterized in that: The thickness of the photoresist film is 100 nm to 500 nm; And / or, the thickness of the film layer is 90 nm~110 nm.

8. A calibration plate, characterized in that: The calibration plate is prepared by the preparation method according to any one of claims 1 to 7.

9. The calibration plate according to claim 8, characterized in that: The calibration plate is divided into 13 levels of arrays, each level of the array is composed of 2*50 marking points, the spacing of each level of the array is 0.1 mm, and the position spacing error of the marking points is less than ±100nm; the sizes of the marking points are 2000 nm, 1500 nm, 1200 nm, 1000 nm, 900 nm, 800 nm, 700nm, 600 nm, 500 nm, 400 nm, 300 nm, 200 nm, and 100 nm, respectively.

10. Use of the calibration plate according to claim 8 or 9 in precision inspection of semiconductor testing equipment.

Images