CN-121985791-A - Wafer chamfering detection method and computer equipment

CN121985791ACN 121985791 ACN121985791 ACN 121985791ACN-121985791-A

Abstract

The invention discloses a wafer chamfering detection method and computer equipment, and relates to the technical field of LEDs, wherein the method comprises the steps of obtaining reference positions of wafers in a wafer box; the wafer is conveyed to a first vacuum adsorption table of a center positioning mechanism according to a reference position by a driving and conveying hand to center position the wafer, the wafer is conveyed to a second vacuum adsorption table of an edge surface width measuring mechanism by the driving and conveying hand, image information of the side wall of the wafer in the rotating process is obtained by driving and conveying the second vacuum adsorption table to rotate, the surface width of the flat edge position and the circumferential position of the wafer are calculated according to the image information respectively, the wafer is conveyed to a third vacuum adsorption table of a diameter measuring mechanism by the driving and conveying hand, the distance, the maximum diameter and the minimum diameter between the flat edge position and the circle center of the wafer are measured by driving and conveying hand to move the wafer to the reference position corresponding to the wafer. By adopting the invention, the measuring speed and the measuring precision can be effectively improved.

Inventors

ZHAO YUANYA
CHEN TIAN
WEN GUOSHENG
HU JIAHUI
Jin Conglong

Assignees

江西兆驰半导体有限公司

Dates

Publication Date: 20260505
Application Date: 20260403

Claims (10)

1. The wafer chamfering detection method is characterized by comprising the following steps of: Acquiring a reference position of each wafer in the wafer box; driving a carrying hand to send the wafer to a first vacuum adsorption table of a centering mechanism according to the reference position so as to center the wafer; driving the carrying hand to send the wafer to a second vacuum adsorption table of the edge surface amplitude measuring mechanism; driving the second vacuum adsorption table to rotate so as to acquire image information of the side wall of the wafer in the rotating process, and respectively calculating the plane width of the flat edge position and the circumferential position of the wafer according to the image information; driving the carrying hand to send the wafer to a third vacuum adsorption table of a diameter measuring mechanism; Driving the third vacuum adsorption table to rotate so as to measure the distance, the maximum diameter and the minimum diameter between the flat edge position and the circle center of the wafer; and driving the carrying hand to move the wafer to the reference position corresponding to the wafer.
2. The wafer chamfering inspection method as set forth in claim 1, wherein the step of acquiring the reference position of each wafer in the cassette comprises: driving a loading and unloading mechanism to enable the wafer box on the loading and unloading mechanism to move back and forth along a specific direction; And in the moving process of the wafer box, the scanning sensor is driven to scan the wafer box so as to acquire the reference position of each wafer in the wafer box.
3. The wafer bevel inspection method of claim 1 wherein the step of centering the wafer comprises: the first positioning plate and the second positioning plate of the driving center positioning mechanism simultaneously move to the circle center position of the first vacuum adsorption table so as to push the center of the wafer to move to the circle center position of the first vacuum adsorption table, and the first positioning plate and the second positioning plate are oppositely arranged on two sides of the first vacuum adsorption table; When the first positioning plate and the second positioning plate are simultaneously contacted with the circumference of the wafer, the first positioning plate and the second positioning plate are driven to stop moving; driving the first vacuum adsorption table to start vacuum so as to adsorb the wafer; and driving the first positioning plate and the second positioning plate to simultaneously reversely move towards the center position of the first vacuum adsorption table.
4. The wafer chamfering inspection method as set forth in claim 1, wherein said step of driving said second vacuum chuck to rotate to obtain image information of said wafer sidewall during rotation, and calculating the plane width of said wafer at the flat edge position and the circumferential position, respectively, based on said image information includes: Driving the second vacuum adsorption table to rotate, wherein light rays emitted from a sensor emission end in the rotation process pass through the side wall of the wafer and enter a sensor receiving end; identifying the flat edge position of the wafer according to the optical signal received by the sensor receiving end; When the light signal of the flat edge position is identified, driving the second vacuum adsorption table to rotate by a first angle, stopping and driving the image acquisition equipment to acquire image information of light spots with wafer side wall characteristics, and calculating the width of the flat edge position according to the image information; And driving the second vacuum adsorption table to rotate a second angle, stopping and driving the image acquisition equipment to acquire image information of light spots with wafer side wall characteristics, and calculating the width of the surface of the circumferential position according to the image information.
5. The wafer chamfering inspection method according to claim 1 or 4, characterized in that the step of calculating the width of the web when the sidewall of the wafer is chamfered in a trapezoid includes: Forming a first straight line at the upper plane of the wafer, forming a second straight line at the lower plane of the wafer, forming a third straight line at the upper inclined plane of the wafer, forming a fourth straight line at the lower inclined plane of the wafer, and forming a fifth straight line at the end face of the wafer; extracting a first intersection point between the first straight line and a third straight line, a second intersection point between the second straight line and a fourth straight line, a third intersection point between the third straight line and a fifth straight line and a fourth intersection point between the fourth straight line and the fifth straight line; calculating a vertical distance between the first intersection point and the third intersection point as an upper web width; the vertical distance between the second intersection point and the fourth intersection point is calculated as the following web width.
6. The wafer chamfering detection method according to claim 1 or 4, characterized in that the step of calculating the width of the face when the side wall of the wafer is chamfered with an arc comprises: The upper plane of the wafer is at a point to form a first straight line, the lower plane of the wafer is at a point to form a second straight line, and the semicircular surface of the wafer is at a point to form a circular arc line; Extracting a first intersection point between the first straight line and the circular arc line, a second intersection point between the second straight line and the circular arc line and a midpoint of the circular arc line; calculating a vertical distance between the first intersection point and a midpoint as an upper web width; the vertical distance between the second intersection point and the midpoint is calculated as the following web width.
7. The wafer chamfering inspection method as set forth in claim 6, further comprising adjusting a grinding wheel position according to said face width, the steps comprising: When the difference between the upper width and the lower width of the wafer is larger than a preset error, if the upper width is larger than the lower width, the grinding position of the grinding wheel is moved downwards, and if the lower width is larger than the upper width, the grinding position of the grinding wheel is moved upwards; when the width of the surface at the circumferential position of the wafer is smaller than the preset minimum circumferential width, adjusting the vertical feeding direction of the grinding wheel along the direction of the wafer; When the width of the surface at the circumferential position of the wafer is larger than the preset maximum circumferential width, adjusting the vertical feeding direction of the grinding wheel along the opposite direction of the wafer; when the width of the flat edge of the wafer is smaller than the preset minimum flat edge width, adjusting the vertical feeding direction of the grinding wheel along the direction of the wafer; and when the width of the flat edge of the wafer is larger than the preset maximum flat edge width, adjusting the vertical feeding direction of the grinding wheel along the opposite direction of the wafer.
8. The wafer chamfering inspection method according to claim 1, wherein the step of driving the third vacuum suction table to rotate to measure a distance, a maximum diameter, and a minimum diameter between a flat side position and a center of a circle of the wafer comprises: According to at least six preset point taking frames, taking points are arranged on the edge of the wafer, wherein the point taking frames have the same reference circle center, one point taking frame is arranged at the flat edge position, the other point taking frames are arranged at the circumference position, the point taking frames are combined in pairs to form a point taking frame group, two point taking frames in the same point taking frame group are arranged on the same diameter corresponding to the reference circle center, and two reference points are taken in each point taking frame; Driving the third vacuum adsorption table to rotate, wherein reference points in each point taking frame group respectively and simultaneously fall into a measuring range of the diameter measuring mechanism in the rotating process, and the measuring range comprises two measuring areas which are arranged on the same diameter and correspond to the reference circle center; The driving diameter measuring mechanism respectively measures the distance between two point taking frames in the measuring range, takes the measured maximum value of the distance as the maximum diameter and takes the measured minimum value of the distance as the minimum diameter; constructing virtual dots according to the datum points arranged on the circumferential positions; when the reference points in the point taking frame groups of the point taking frames arranged on the flat edge positions are all in the measuring range, extracting the center points between the reference points on the flat edge positions, and calculating the distance between the center points and the virtual dots to be used as the distance between the flat edge positions and the circle centers.
9. The method for inspecting a wafer bevel according to claim 1 or 8, further comprising adjusting a grinding wheel position according to a distance between the flat side position and a center of a circle, a maximum diameter, and a minimum diameter, comprising the steps of: when the distance between the flat edge position and the circle center is smaller than the preset minimum distance, the feed amount of the grinding wheel during grinding is reduced; when the distance between the flat edge position and the circle center is larger than the preset maximum distance, increasing the feed amount of the grinding wheel during grinding; When the minimum diameter is smaller than a preset minimum threshold value, reducing the theta axial feeding coordinate value of the grinding wheel; and when the maximum diameter is larger than a preset maximum threshold value, increasing the theta axial feeding coordinate value of the grinding wheel.
10. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the wafer bevel inspection method of any of claims 1 to 9 when the computer program is executed.

Description

Wafer chamfering detection method and computer equipment Technical Field The invention relates to the technical field of LEDs, in particular to a wafer chamfering detection method and computer equipment. Background At present, the LED chip substrate material is mainly a sapphire substrate sheet, and because the sapphire material is high in brittleness, sharp edges generated in the processing process are easy to cause stress concentration, the problems of wafer fragmentation, epitaxial layer defects, uneven photoresist coating and the like can be caused in the subsequent processing, so that the yield and the reliability of a semiconductor device are directly affected, and in order to reduce the influence, the wafer needs chamfering after cutting and grinding. The chamfering process generally adopts a metal bond diamond grinding wheel to grind the edge of a wafer at a high speed, and the right-angle side wall is processed into an arc-shaped or trapezoid-shaped structure ‌ through the relative motion of the grinding wheel with an arc or trapezoid-shaped groove at the edge and a wafer, and the process needs to be equipped with high-precision numerical control chamfering equipment. The main stream of numerical control chamfering equipment mainly comprises tokyo precision, NTS and Qingdao high measurement, after chamfering, all the chamfering equipment has no full-automatic inspection device, manual inspection is needed, a hand-held microscope is used for inspecting the front edge and the back edge, a vernier caliper is used for measuring the diameter size of a wafer, whether the quality after chamfering meets the requirement is confirmed, and the parameters are adjusted according to the measured values, so that the machining precision is gradually corrected, and the target size precision is achieved. However, as a result, the vernier caliper is easy to break edges when touching the circumference of the wafer, the labor input is large, the measurement efficiency is low, meanwhile, the measurement is inaccurate due to the measurement method difference of personnel, the personnel understand the processing principle and the program parameter setting, the adjustment method is different, the processing parameters cannot be adjusted to the optimal state in time, and the quality errors of the surface width and the diameter of the wafer after chamfering are large. Disclosure of Invention The invention aims to solve the technical problem of providing a wafer chamfering detection method and computer equipment, which can effectively improve the measurement speed and the measurement precision. In order to solve the technical problems, the wafer chamfering detection method comprises the steps of obtaining the reference position of each wafer in a wafer box, driving a carrying hand to send the wafer to a first vacuum adsorption table of a center positioning mechanism according to the reference position so as to center the wafer, driving the carrying hand to send the wafer to a second vacuum adsorption table of an edge surface width measuring mechanism, driving the second vacuum adsorption table to rotate so as to obtain image information of the side wall of the wafer in the rotating process, respectively calculating the surface width of the flat edge position and the circumferential position of the wafer according to the image information, driving the carrying hand to send the wafer to a third vacuum adsorption table of a diameter measuring mechanism, driving the third vacuum adsorption table to rotate so as to measure the distance, the maximum diameter and the minimum diameter between the flat edge position and the center of the wafer, and driving the carrying hand to move the wafer to the reference position corresponding to the wafer. The method for acquiring the reference positions of the wafers in the wafer box comprises the steps of driving the feeding and discharging mechanism to enable the wafer box on the feeding and discharging mechanism to move back and forth along a specific direction, and driving the scanning sensor to scan the wafer box to acquire the reference positions of the wafers in the wafer box in the moving process of the wafer box. The wafer center positioning method comprises the steps of driving a first positioning plate and a second positioning plate of a center positioning mechanism to move towards the center of a first vacuum adsorption table at the same time so as to push the center of the wafer to move towards the center of the first vacuum adsorption table, enabling the first positioning plate and the second positioning plate to be arranged on two sides of the first vacuum adsorption table in opposite directions, driving the first positioning plate and the second positioning plate to stop moving when the first positioning plate and the second positioning plate are in contact with the circumference of the wafer at the same time, driving the first vacuum adsorption table to start vacuum to adsorb th