# US 12,183,616 B2 · Method and system for positioning center of V-type notch of wafer, and computer storage medium

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,183,616 B2
- Document ID: US12183616B2
- Status: Granted
- Kind: B2
- Application number: 18/568,629
- Filed: 2022-10-21
- Published: 2024-08-08
- Granted: 2024-12-31
- Earliest claimed: 2021-10-21
- Assignees: Xi'an Eswin Material Technology Co., Ltd.; Xi'an Eswin Silicon Wafer Technology Co., Ltd.
- Applicants: Xi'an Eswin Material Technology Co., Ltd.; Xi'an Eswin Silicon Wafer Technology Co., Ltd.
- Inventors: Leilei Wang; Xun Lan; Housheng Li
- Web page: https://patentgrep.com/patent/US12183616B2

## CPC

- H10P 72/53: {using optical controlling means}
- G01B 11/24: for measuring contours or curvatures
- G01B 11/272: {using photoelectric detection means}
- H10P 72/50: for positioning, orientation or alignment
- H10P 72/78: using vacuum or suction, e.g. Bernoulli chucks
- H10P 74/203: {Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects}
- H10P 74/23: {characterised by multiple measurements, corrections, marking or sorting processes}
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
- G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS

## Abstract

A method is for positioning a center of a V-type notch of a wafer. The method includes: determining, based on collected edge data of a V-type notch of a wafer, a center of a concentric circle corresponding to edges of the V-type notch; and judging, based on a position relation between the center and a set reference scale line, whether the V-type notch is at a preset target center position. The method also includes determining, based on the position relation between the center and the set reference scale line, a rotation direction and rotation angle of the wafer when the V-type notch is out of the preset target center position; and driving, according to the rotation direction and rotation angle of the wafer, the wafer to rotate until the V-type notch is rotated to the preset target center position.

## Claims

### Claim 1

A method for positioning a center of a V-type notch of a wafer, comprising:
determining, based on collected edge data of the V-type notch of the wafer, a center of a concentric circle corresponding to edges of the V-type notch; wherein the determining, based on the collected edge data of the V-type notch of the wafer, the center of the concentric circle corresponding to the edges of the V-type notch comprises:
rotating the wafer until the V-type notch is rotated to below a line laser contour detection sensor;
using the line laser contour detection sensor to collect coordinates of each edge point of the V-type notch;
obtaining, based on the coordinates of each edge point, coordinate (XO, YO) of a center O of the concentric circle corresponding to the edges of the V-type notch by using least squares;
judging, based on a position relation between the center and a set reference scale line, whether the V-type notch is at a preset target center position; wherein the judging, based on the position relation between the center and the set reference scale line, whether the V-type notch is at a preset target center position, comprises:
obtaining a distance L between the center O and the set reference scale line;
determining that the V-type notch is at the preset target center position when the distance L=0 or the distance L is within a preset range;
determining that the V-type notch is out of the preset target center position and continuing positioning the center of the V-type notch, when the distance L is without a preset range;
wherein the preset range is the distance L=0±0.001 mm between the center O of the concentric circle and the set reference scale line;
determining, based on the position relation between the center and the set reference scale line, a rotation direction and rotation angle of the wafer, when the V-type notch is out of the preset target center position; and
driving, according to the rotation direction and rotation angle of the wafer, the wafer to rotate until the V-type notch is rotated to the preset target center position.

### Claim 2 (depends on 1)

The method according to claim 1, wherein the obtaining, based on the coordinates of each edge point, coordinates (XO, YO) of a center O of the concentric circle corresponding to the edges of the V-type notch by using least squares, comprising:
selecting three non-repeating edge points, and fitting and obtaining, based on the coordinates of the three non-repeating edge points, the coordinate (XO, YO) of the center O corresponding to the edges of the V-type notch by using the least squares.

### Claim 3 (depends on 1)

The method according to claim 1, wherein the determining, based on the position relation between the center and the set reference scale line, the rotation direction and rotation angle of the wafer when the V-type notch is out of the preset target center position, comprises:
determining, according to a formula θ=180L/πD, a rotation angle θ of the wafer based on the distance L between the center O and the set reference scale line and a distance D between the center O and a center O1 of the wafer, when the V-type notch is out of the preset target center position;
determining, based on the position relation between the center O and the preset reference scale line, the rotation direction of the wafer.

### Claim 4 (depends on 3)

The method according to claim 3, wherein the determining, based on the position relation between the center O and the set reference scale line, the rotation direction of the wafer, comprises:
setting, in an XO1Y plane of a Cartesian coordinate system, the distance L>0 when the center O is at a right side of the reference scale line, the distance L<0 when the center O is at a left side of the reference scale line;
determining that the rotation direction of the wafer is counterclockwise when the distance L>0; or,
determining that the rotation direction of the wafer is clockwise when the distance L<0.

### Claim 5 (depends on 1)

A computer storage medium, comprising a program for positioning a center of a V-type notch of a wafer stored thereon; wherein the program is executed by at least one processor to perform the method according to claim 1.

### Claim 6

A positioning system for a center of a V-type notch of a wafer, comprising: a first determining portion, a judging portion, a second determining portion and a rotating portion;
wherein
the first determining portion is configured to determine, based on collected edge data of the V-type notch of the wafer, a center of a concentric circle corresponding to edges of the V-type notch; wherein determining, based on the collected edge data of the V-type notch of the wafer, the center of the concentric circle corresponding to the edges of the V-type notch comprises:
rotating the wafer until the V-type notch is rotated to below a line laser contour detection sensor;
using the line laser contour detection sensor to collect coordinates of each edge point of the V-type notch;
obtaining, based on the coordinates of each edge point, coordinate (XO, YO) of the center O of the concentric circle corresponding to the edge of the V-type notch by using least squares;
the judging portion is configured to judge, based on a position relation between the center and a set reference scale line, whether the V-type notch is at a preset target center position; wherein the judging, based on the position relation between the center and the set reference scale line, whether the V-type notch is at a preset target center position comprises:
obtaining a distance L between the center O and the preset reference scale line;
determining that the V-type notch is at the preset target center position when the distance L=0 or the distance L is within a preset range;
determining that the V-type notch is out of the preset target center position and continuing positioning the center of the V-type notch, when the distance L is without a preset range; wherein the preset range is the distance L=0±0.001 mm between the center O of the concentric circle and the set reference scale line;
the second determining portion is configured to determine, based on the position relation between the center and the set reference scale line, a rotation direction and rotation angle of the wafer when the V-type notch is out of the preset target center position;
the rotating portion is configured to drive, according to the rotation direction and rotation angle of the wafer, the wafer to rotate until the V-type notch is rotated to the preset target center position.

### Claim 7

A system for positioning a center of a V-type notch of a wafer, comprising: a positioning back plate for positioning a wafer with the center of the V-type notch, a vacuum suction cup, a line laser contour detection sensor, a data processing device, and a servo motor; wherein
the positioning back plate is provided with a circular hole that cooperates with the vacuum suction cup, and the vacuum suction cup is embedded in the circular hole;
the vacuum suction cup is used to adsorb the wafer with a back of the wafer tightly attached to the positioning back plate;
the line laser contour detection sensor is used to collect edge data of the V-type notch;
the data processing device is configured to:
determine, based on collected edge data of the V-type notch of the wafer, a center of a concentric circle corresponding to edges of the V-type notch; wherein the determining, based on the collected edge data of the V-type notch of the wafer, the center of the concentric circle corresponding to the edges of the V-type notch comprises:
rotating the wafer until the V-type notch is rotated to below a line laser contour detection sensor;
using the line laser contour detection sensor to collect coordinates of each edge point of the V-type notch;
obtaining, based on the coordinates of each edge point, coordinate (XO, YO) of the center O of the concentric circle corresponding to the edges of the V-type notch by using least squares;
judge, based on a position relation between the center and a set reference scale line, whether the V-type notch is at a preset target center position; wherein the judging, based on the position relation between the center and the set reference scale line, whether the V-type notch is at a preset target center position comprises:
obtaining a distance L between the center O and the preset reference scale line;
determining that the V-type notch is at the preset target center position when the distance L=0 or the distance L is within a preset range;
determining that the V-type notch is out of the preset target center position and continuing positioning the center of the V-type notch, when the distance L is without a preset range; wherein the preset range is the distance L=0±0.001 mm between the center O of the concentric circle and the set reference scale line;
determining, based on the position relation between the center and the set reference scale line, a rotation direction and rotation angle of the wafer when the V-type notch is out of the preset target center position; and,
outputting, according to the rotation direction and rotation angle of the wafer, a control signal;
the servo motor is configured to drive the wafer to rotate clockwise or counterclockwise until the V-type notch is located below the line laser contour detection sensor; and drive, based on the control signal, the wafer to rotate according to the rotation direction and rotation angle of the wafer, until the V-type notch is rotated to the preset target center position.