Method for automatically judging silicon wafer particle overlay graph based on algorithm

Abstract

The invention relates to an algorithm-based automatic judgment method for silicon wafer particle overlay, which belongs to the technical field of silicon wafer detection, adopts an SPX machine table to test and overlay 12-inch silicon wafers, and comprises the following operation steps of: 1, dividing the silicon wafers into a first quadrant, a second quadrant, a third quadrant and a fourth quadrant by taking the circle center of the silicon wafers as an original point; 2, taking the circle center of the silicon wafer as an original point, taking 35mm, 100mm and 142mm as radiuses, and respectively obtaining a ZONE1 region, a ZONE2 region and a ZONE3 region; and 3, judging NG when the number of defects of ONE1 + ZONE2 + ZONE3 is larger than 1000, judging OK when the number of defects of ONE1 + ZONE2 + ZONE3 is smaller than 15, and entering the next step when the number of And 4, comparing the defect numbers of the four quadrants pairwise, judging OK when the ratio is greater than 6, and otherwise, carrying out the next step. And 5, classifying the three areas according to the defect number and the relative density. And 6, when all the conditions are not met, judging as OK. The method has the advantages of convenient operation and good judgment stability. And subjective factor interference can be eliminated while the specific pattern characteristics of the COP silicon wafer are considered.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon wafer detection, and in particular to a method for automatically determining silicon wafer particle overlay based on an algorithm. Background Art

[0002] When testing 12-inch silicon wafer particles, silicon wafers with COP will show special patterns in the test image, such as center aggregation and edge rings. Previously, the identification of such silicon wafers containing COP could only be determined by card control of the total number of particles and visual inspection of samples based on the COP silicon wafer special pattern limit.

[0003] First, the scheme of controlling the total number of particles does not take into account the special pattern of the COP silicon wafer itself. If the total number is set to a large value, it is easy to cause the COP silicon wafer to be missed. If the total number is set to a small value, it is easy to over-judge non-COP silicon wafers as COP silicon wafers.

[0004] Secondly, the visual inspection of COP silicon wafer special pattern limit samples is greatly influenced by the subjective factors of the inspectors, and the judgment results of different inspectors may be different. Summary of the invention

[0005] The present invention mainly solves the deficiencies in the prior art and provides a method for automatically determining silicon wafer particle overlay based on an algorithm, which has the advantages of convenient operation and good judgment stability, and can eliminate the interference of subjective factors while taking into account the special pattern characteristics of COP silicon wafers.

[0006] The above technical problems of the present invention are mainly solved by the following technical solutions: A method for automatically determining silicon wafer particle overlay based on an algorithm, using a 12-inch silicon wafer tested and overlaid by an SPX machine, includes the following steps: Step 1: Take the center of the silicon wafer as the origin and divide it into the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant.

[0007] Step 2: Take the center of the silicon wafer as the origin and 35mm, 100mm, and 142mm as the radius to obtain ZONE1, ZONE2, and ZONE3 areas respectively.

[0008] Step 3: If the number of defects in ONE1+ZONE2+ZONE3 is greater than 1000, it is judged as NG; if it is less than 15, it is judged as OK; if it is between 15 and 1000, proceed to the next step.

[0009] Step 4: Compare the defect numbers in the four quadrants in pairs. If the ratio is greater than 6, it is determined to be OK, otherwise proceed to the next step.

[0010] Step 5: Classify the three areas according to the number and relative density of defects.

[0011] Step 6: If none of the above conditions are met, it is judged as OK.

[0012] Preferably, ZONE1 is a green circular area, ZONE2 is a red circular area, and ZONE3 is a yellow circular area; the area ratio of the three areas is calculated to obtain ZONE1:ZONE2:ZONE3=1:7.16:8.3.

[0013] Preferably, the defects that need to be considered are screened out through the Klarf file after the particle test, the number of defects in each area is calculated in detail, and the relative density between each area is obtained by using the particle number / area ratio.

[0014] As a preference, ZONE1 has the largest relative density, which is twice or more than that of ZONE2. At the same time, the number of defects in ZONE1 is greater than 10, which is judged as NG, and the mode is center aggregation.

[0015] As a preference, ZONE3 has the largest relative density, which is 3.2 times or more of that of ZONE2. Meanwhile, the number of defects in ZONE3 is greater than 60, which is judged as NG, and the mode is edge aggregation.

[0016] The present invention can achieve the following effects: The present invention provides a method for automatically determining silicon wafer particle overlay based on an algorithm, which has the advantages of convenient operation and good determination stability compared with the prior art, and can eliminate the interference of subjective factors while taking into account the special pattern characteristics of COP silicon wafers. DETAILED DESCRIPTION

[0017] The technical solution of the invention is further specifically described below through embodiments.

[0018] Embodiment: A method for automatically determining silicon wafer particle overlay based on an algorithm, using a 12-inch silicon wafer tested and overlaid by an SPX machine, includes the following steps: Step 1: Take the center of the silicon wafer as the origin and divide it into the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant.

[0019] Step 2: Take the center of the silicon wafer as the origin and 35mm, 100mm, and 142mm as the radius to obtain ZONE1, ZONE2, and ZONE3 areas respectively.

[0020] ZONE1 is the green circular area, ZONE2 is the red circular area, and ZONE3 is the yellow circular area. By calculating the area ratio of the three areas, we get ZONE1:ZONE2:ZONE3=1:7.16:8.3.

[0021] Through the Klarf file after the particle test, the defects that need to be considered are screened out, the number of defects in each area is calculated in detail, and the relative density between each area is obtained using the particle number / area ratio.

[0022] Step 3: If the number of defects in ONE1+ZONE2+ZONE3 is greater than 1000, it is judged as NG; if it is less than 15, it is judged as OK; if it is between 15 and 1000, proceed to the next step.

[0023] Step 4: Compare the defect numbers in the four quadrants in pairs. If the ratio is greater than 6, it is determined to be OK, otherwise proceed to the next step.

[0024] Step 5: Classify the three areas according to the number and relative density of defects.

[0025] ZONE1 has the largest relative density, which is twice or more than that of ZONE2. At the same time, the number of defects in ZONE1 is greater than 10, which is judged as NG, and the mode is center aggregation.

[0026] ZONE3 has the largest relative density, which is 3.2 times or more than that of ZONE2. At the same time, the number of defects in ZONE3 is greater than 60, which is judged as NG, and the mode is edge aggregation.

[0027] Step 6: If none of the above conditions are met, it is judged as OK.

[0028] After the images were overlaid, the results were automatically judged and manually checked twice. A total of 933 images were found, 1 was missed, 29 were over-judged, the missed rate was 0.11%, the over-judgment rate was 3.12%, and the accuracy rate was 96.77%. Except for the silicon wafers with both serious processing anomalies and COP, the rest could be classified.

[0029] In summary, the algorithm-based method for automatic determination of silicon wafer particle overlay has the advantages of convenient operation and good judgment stability. It can eliminate the interference of subjective factors while taking into account the special pattern characteristics of COP silicon wafers.

[0030] The above description is only a specific embodiment of the present invention, but the structural features of the present invention are not limited thereto. Any changes or modifications made by any technician in the field of the present invention are included in the patent scope of the present invention.

Claims

1. A method for automatically determining silicon wafer particle overlay based on an algorithm, characterized in that: The 12-inch silicon wafer tested and overlaid using the SPX machine includes the following steps: Step 1: Taking the center of the silicon wafer as the origin, divide it into the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant; Step 2: Take the center of the silicon wafer as the origin, and 35mm, 100mm, and 142mm as the radius to obtain ZONE1, ZONE2, and ZONE3 respectively; Step 3: If the number of defects in ONE1+ZONE2+ZONE3 is greater than 1000, it is judged as NG; if it is less than 15, it is judged as OK; if it is between 15 and 1000, it proceeds to the next step; Step 4: Compare the number of defects in the four quadrants in pairs. If the ratio is greater than 6, it is determined to be OK, otherwise proceed to the next step; Step 5: Classify the three areas according to the number and relative density of defects; Step 6: If none of the above conditions are met, it is judged as OK.

2. The method for automatically determining silicon wafer particle overlay based on an algorithm according to claim 1, characterized in that: ZONE1 is the green circular area, ZONE2 is the red circular area, and ZONE3 is the yellow circular area. By calculating the area ratio of the three areas, we get ZONE1:ZONE2:ZONE3=1:7.16:8.

3.

3. The method for automatically determining silicon wafer particle overlay based on an algorithm according to claim 2, characterized in that: Through the Klarf file after the particle test, the defects that need to be considered are screened out, the number of defects in each area is calculated in detail, and the relative density between each area is obtained using the particle number / area ratio.

4. The method for automatically determining silicon wafer particle overlay based on an algorithm according to claim 1, characterized in that: ZONE1 has the largest relative density, which is twice or more than that of ZONE2. At the same time, the number of defects in ZONE1 is greater than 10, which is judged as NG, and the mode is center aggregation.

5. The method for automatically determining silicon wafer particle overlay based on an algorithm according to claim 1, characterized in that: ZONE3 has the largest relative density, which is 3.2 times or more than that of ZONE2. At the same time, the number of defects in ZONE3 is greater than 60, which is judged as NG, and the mode is edge aggregation.