CN-122008059-A - Wafer front and back face recognition processing method and device and wafer grinding equipment

CN122008059ACN 122008059 ACN122008059 ACN 122008059ACN-122008059-A

Abstract

The invention discloses a wafer front and back face identification processing method, a device and wafer grinding equipment, wherein the method comprises the steps of collecting a reflection image formed by reflecting a marker through a detection face of a wafer, wherein the marker has preset marking characteristics; and comparing the characteristic parameters with preset conditions to identify the front side and the back side of the detection surface. The wafer grinding equipment comprises a grinding device and a wafer front and back recognition processing device, wherein the wafer front and back recognition processing device recognizes the front and back of the wafer, and transmits a control command corresponding to the recognition result to the grinding device so as to enable the grinding device to execute corresponding actions. Compared with the prior art, the invention has the advantages of high accuracy of detecting the front and the back and low cost of the device.

Inventors

Han Chaolu
LIU KUNQI
ZHONG HAN
FU YU
LI QUAN
GUO WEIGANG
LIANG GUANGLIANG

Assignees

广东泰来封测科技有限公司

Dates

Publication Date: 20260512
Application Date: 20251229

Claims (13)

1. The wafer front and back face recognition method is characterized by comprising the following steps: Collecting a reflection image formed by reflecting a marker through a detection surface of a wafer, wherein the marker has preset marking characteristics; Identifying a characteristic image of the marking characteristic in the reflected image, and obtaining a characteristic parameter of the characteristic image; and comparing the characteristic parameters with preset conditions to identify the front and back sides of the detection surface.
2. The method of claim 1, wherein the marker comprises a light source having a predetermined light emission shape, the predetermined light emission shape forming the marking feature, or The marker includes a reflective object having a predetermined reflective shape that forms the marking feature.
3. The method for identifying front and back sides of a wafer as set forth in claim 1, wherein said characteristic parameters include one or more of a blur parameter, a brightness parameter, and an area parameter, and the detection surface is identified as a back side when all the characteristic parameters satisfy a predetermined condition, and the detection surface is identified as a front side when any of the characteristic parameters does not satisfy the predetermined condition.
4. The wafer front-back surface recognition method as set forth in claim 3, wherein: When the characteristic parameters comprise fuzzy parameters, calculating the contrast of the characteristic images and the background thereof in the reflected images as the fuzzy parameters, judging that the fuzzy parameters meet preset conditions when the contrast is larger than or equal to a contrast preset value, and judging that the fuzzy parameters do not meet the preset conditions when the contrast is smaller than the contrast preset value; When the characteristic parameters comprise brightness parameters, calculating brightness of the characteristic image as the brightness parameters, judging that the brightness parameters meet preset conditions when the brightness parameters are larger than or equal to brightness preset values, and judging that the brightness parameters do not meet the preset conditions when the brightness of the characteristic image is smaller than the brightness preset values; When the characteristic parameters comprise area parameters, calculating the area size of the characteristic image as the area parameters, judging that the area parameters meet preset conditions when the area parameters are smaller than or equal to preset area values, and judging that the area parameters do not meet the preset conditions when the area parameters are larger than the preset area values.
5. The method of claim 2, wherein the marking features are in the form of dots or blocks, the marking features are arranged in a plurality of intervals, and the feature images have corresponding dot-shaped features or block-shaped features.
6. The method for recognizing front and back sides of a wafer as set forth in claim 5, wherein a minimum distance between adjacent marking features is a first predetermined distance so that feature images in the reflected images reflected by the back side of the wafer are distributed in a dot shape, and at least two feature images in the reflected images reflected by the front side of the wafer are connected together; the feature parameters comprise the number of images, the number of the feature images is calculated to be used as the number of the images, the preset condition comprises the number of the images being equal to the number of the marking features, and the detection surface is judged to be the front surface when the number of the images does not accord with the preset condition.
7. The wafer front and back face recognition processing device is characterized by comprising: The optical detection module comprises a marker and an image collector, wherein the marker has preset marking characteristics, a detection position is arranged on a transmission path of a wafer, and the image collector is used for receiving a reflected image of the marker formed by reflection of a detection surface of the wafer; The processing module is connected with the optical detection module and receives the reflected image output by the optical detection module, identifies the characteristic image of the marking characteristic in the reflected image, obtains the characteristic parameter of the characteristic image, and compares the characteristic parameter with a preset condition to identify the front side and the back side of the detection surface.
8. The apparatus of claim 7, wherein the marker comprises a light source having a predetermined light emission shape, the predetermined light emission shape forming the marking feature, or wherein the marker comprises a light reflecting object having a predetermined light reflection shape, the predetermined light reflection shape forming the marking feature.
9. The method of claim 8, wherein the mark features are in the form of dots or blocks, the plurality of mark features are arranged at intervals, and the feature image has corresponding dot-like features or block-like features.
10. The apparatus of claim 7, further comprising a trigger sensor for detecting a wafer in front of the detection position on the transport path, wherein the trigger sensor generates a trigger signal when the wafer is about to reach the detection position, and wherein the processing module is connected to the trigger sensor and controls the optical detection module to acquire the reflected image when the wafer reaches the detection position when the trigger signal is received.
11. The apparatus of claim 7, further comprising an execution unit, wherein the processing module sends the identification result of the detection surface to the execution unit, and the execution unit converts the identification result into a corresponding control command and outputs the control command.
12. The wafer polishing device is characterized by comprising a polishing device and the wafer front and back recognition processing device according to any one of claims 7-11, wherein the polishing device is used for conveying a wafer to a polishing table along a transmission path and polishing the wafer, the wafer front and back recognition processing device is used for acquiring a front and back recognition result of a wafer detection surface on the transmission path and conveying a control command corresponding to the front and back recognition result to the polishing device, and the polishing device executes corresponding actions according to the control command.
13. The wafer polishing apparatus according to claim 12, wherein the polishing device comprises a polishing mechanism for polishing a wafer and having a polishing table, a wafer conveyance mechanism for conveying the wafer to the polishing table along a conveyance path, and an alarm mechanism, wherein the processing module outputs a release command to the polishing device when the inspection surface is a predetermined surface, and the polishing device continues to operate according to the release command to convey the wafer to the polishing table along the conveyance path, and wherein the processing module outputs a failure command to the polishing device when the inspection surface is not the predetermined surface, and wherein the polishing device stops and controls the alarm mechanism to alarm according to the failure command.

Description

Wafer front and back face recognition processing method and device and wafer grinding equipment Technical Field The invention relates to semiconductor manufacturing, in particular to a wafer front and back face recognition processing method and device and a wafer front and back face fool-proof system. Background In the polishing process of semiconductor wafers, the wafers must be placed on the polishing equipment in the correct orientation (typically face down). The conventional feeding link relies on naked eyes of operators to judge the front and back sides of the wafer, and has the inherent defects that 1. The risk of human misjudgment is high, and the characteristic difference of the front and back sides of the wafer is possibly not obvious, and misjudgment is easy to cause especially when the light is insufficient or the personnel is tired. 2. Yield loss, namely once the wafer is reversely put for grinding, the wafer is directly scrapped, and great economic loss is caused. 3. The efficiency is low, the manual inspection speed is low, and the closed loop of the full-automatic production process cannot be realized. 4. Poor consistency, and possible differences in the judgment standards of different operators. Referring to patent CN116364608 a, after collecting the surface image of the wafer, the existing wafer front and back recognition processing device compares the detected image with the standard image to recognize the front and back of the wafer, but because the front line pattern of the wafer is various and is often covered with a protective film such as temporary bonding glue, the traditional image template matching algorithm has high complexity, frequent false alarm, insufficient reliability, and needs high-precision image collection, image processing and image comparison equipment, with high cost. Therefore, there is an urgent need for a wafer front and back surface recognition processing method and apparatus that can solve the above problems. Disclosure of Invention The invention aims to provide a wafer front and back face recognition processing method and device and wafer grinding equipment, which have high detection accuracy and low cost. In order to achieve the above purpose, the invention provides a wafer front and back face identification processing method, which comprises the steps of collecting a reflection image formed by reflecting a marker through a detection face of a wafer, wherein the marker has preset marking characteristics, identifying characteristic images of the marking characteristics in the reflection image to obtain characteristic parameters of the characteristic images, and comparing the characteristic parameters with preset conditions to identify the front and back faces of the detection face. Preferably, the marker comprises a light source having a predetermined light emission shape, the predetermined light emission shape forming the marking feature. The light source is used as the marker, so that the detection process is controllable, and the detection accuracy is further improved. The preset light source may be an LED light source, a point light source, a planar light source, a linear light source, or a light source that irradiates a preset image and is reflected, a light set of the preset image output by the display screen, or the like. Preferably, the marker comprises a retroreflective article having a predetermined retroreflective shape that forms the marking feature. The reflective object is a reflective object having a predetermined characteristic shape (the reflective object forms a predetermined reflective shape), or an object having a predetermined reflective pattern (the predetermined reflective pattern forms a predetermined reflective shape). Preferably, the characteristic parameters include one or more of a blur parameter, a brightness parameter and an area parameter, when all the characteristic parameters meet a preset condition, the detection surface is identified as a reverse surface, and when any one of the characteristic parameters does not meet the preset condition, the detection surface is identified as a front surface. Specifically, when the characteristic parameters include fuzzy parameters, calculating the contrast of the characteristic image and the background thereof in the reflected image as the fuzzy parameters of the marking characteristic, judging that the fuzzy parameters meet preset conditions when the contrast is larger than or equal to a contrast preset value, and judging that the fuzzy parameters do not meet preset conditions when the contrast is smaller than the contrast preset value. Specifically, when the characteristic parameters include brightness parameters, calculating brightness of the characteristic image as the brightness parameters, when the brightness parameters are larger than or equal to a brightness preset value, judging that the brightness parameters meet preset conditions, and when the brightness parameters are smaller tha