US 12,347,714 B1
Wafer positioning and correction method, system, and device
Rongsheng Lyu, Nanjing (CN); Han Zhang, Nanjing (CN); Zhichun Guo, Nanjing (CN); and Zuojun Shen, Moraga, CA (US)
Filed by Hito Robotic System Inc., Chino, CA (US)
Filed on Jan. 10, 2025, as Appl. No. 19/016,609.
Claims priority of application No. 202410050381.8 (CN), filed on Jan. 12, 2024.
Int. Cl. G05B 19/404 (2006.01); H01L 21/68 (2006.01)
CPC H01L 21/681 (2013.01) [G05B 19/404 (2013.01); G05B 2219/37506 (2013.01); G05B 2219/45031 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A wafer positioning and correcting method, the wafer to be measured includes a round edge and a flat edge, characterized in that it includes the following steps:
S1: with respect to a dimension of the wafer to be measured, a predetermined coaxiality error Δ of a center P of the wafer to be measured and a center O of a rotating suction cup, a radius R of the wafer to be measured, a distance L0 between the center O of the rotary suction cup and a emitter position of a optical calibrator, a optical calibrator range s, a transmission ratio k of a motor to the rotary suction cup, and a flat edge calibration threshold t are initialized and set;
S2: real-time acquisition of a motor angle αi and a optical calibrator shading amount si during a rotation of the wafer to be measured on the rotary suction cup, thereby calculating a rotation angle θi of the wafer to be measured and a distance ρi between the edge of the wafer to be measured and the center O of the rotary suction cup;
S3: determining the distance ρi between the edge of the wafer to be measured and the center O of the rotary suction cup is within a specified range: in response to determining that the distance ρi between the edge of the wafer to be measured and the center O of the rotary suction cup is within the specified range; continuing with step S4;
S4: determine whether the distance ρi is round edge data or flat edge data:
if rounded edge data, then calculate a polar coordinate position deviation between the center P of the wafer to be measured and the center O of the rotating suction cup on a polar coordinate system (ρp,θp), where ρp is a radius deviation of the wafer center P to be measured relative to the center O of the rotating suction cup, θp is phase deviation relative to the center O of the rotary suction cup; or
if flat edge data, the phase deviation θp is the phase deviation of the center P of the wafer to be measured relative to the center O of the rotating suction cup obtained from the rounded edge data before a jump; wherein phase deviation θp is to calculate a flat edge angle phase deviation β;
S5: use the radius deviation ρp of the center P of the wafer to be measured P relative to the rotating suction cup center O, the center P of the wafer to be measured P, phase deviation θp relative to the center O of the rotating suction cup, and the flat edge angle phase deviation β to place the wafer to be measured for;
wherein, the wafer to be measured is placed on a rotary suction cup, the rotary suction cup is connected to the motor, the rotary suction cup drives the wafer to be tested, wherein the edge of the wafer to be measured is set in the calibration area between a transmitter and a receiver of the optical calibrator, wherein the edge of the wafer to be measured is set in the calibration zone between a transmitter and a receiver of the optical calibrator, wherein the optical calibrator shading amount si is a shading length of the edge of the wafer to be tested between the transmitter and the receiver of the optical calibrator, wherein the length of the shading of the wafer to be measured between the transmitter and the receiver of the optical calibrator.