Patent ID: 11961749
Assignee: HANGZHOU SIZONE ELECTRONIC TECHNOLOGY INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 12:
13. A wafer detection method realized with the wafer detection devices according to claim 7, which is used for detecting whether the wafer is clamped by the clamping jaw inside the CMP cleaning and drying device and whether the wafer is parallel to the bottom of the clamping jaw, and including following steps:
step S1, the wafer detecting unit emits a wafer detecting laser beam to the work plane; the wafer detecting unit receives the emitted wafer detecting laser beam, coverts the optical signal of the received wafer detecting laser beam into the second electrical signal or generates the distance value on basis of the received wafer detecting laser beam;
step S2, the detection processing unit coverts the second electrical signal into a second digital signal corresponding to which, if a value of the second digital signal is 0, the detection processing unit will judge that the wafer is clamped by the clamping jaw and enter step S3; or the detection processing unit compares the distance value with the distance threshold value saved in the detection processing unit, if the distance value is below the distance threshold value, the detection processing unit will judge that the wafer is clamped by the clamping jaw and enter the step S3; otherwise, the detection processing unit will judge that no wafer is clamped by the clamping jaw;
the step S3, the wafer parallel measuring unit emits the parallel measuring laser beam having different frequencies and parallel to the bottom of the clamping jaw; a distance between the parallel measuring laser beam and the bottom of the clamping jaw match with a distance between the work plane and the bottom of the clamping jaw; the wafer parallel measuring unit receives the parallel measuring laser beam and converts the optical signal of the received parallel measuring laser beam into the corresponding first electrical signal; enter step S4; and
the step S4, the detection processing unit coverts the first electrical signal into a first digital signal corresponding to which, if a value of the first digital signal is below a first threshold value saved in the detection processing unit, the detection processing unit will judge that the wafer is not parallel to the bottom of the clamping jaw; otherwise, the detection processing unit will judge that the wafer is parallel to the bottom of the clamping jaw.