Wafer detection device and wafer detection method using the same

A wafer detection device, a wafer is static and placed inside a CMP cleaning and drying device by a clamping jaw;

• a periphery of the wafer is clamped by a clamping part at a top of the clamping jaw and placed on a work plane, the wafer is parallel to a bottom of the clamping jaw and there is a certain distance between the wafer and the bottom of the clamping jaw;
• the wafer detection device is used for detecting whether the wafer is clamped by the clamping jaw inside the CMP cleaning and drying device and detecting whether the wafer is parallel to the bottom of the clamping jaw;
• wherein the wafer detection device includes:
• a wafer parallel measuring unit, which is set inside the CMP cleaning and drying device and is used for emitting a parallel measuring laser beam have different frequencies parallel to the bottom of the clamping jaw and receiving the parallel measuring laser beam;
• when the wafer is parallel to the bottom of the clamping jaw, the parallel measuring laser beam will not be blocked by the wafer;
• an optical signal of the received parallel measuring laser beam converted by the wafer parallel measuring unit corresponds to a first electrical signal;
• a wafer detecting unit, which is set inside the CMP cleaning and drying device and is used for emitting a wafer detecting laser beam to the wafer and receiving the wafer detecting laser beam;
• an optical signal of the received wafer detecting laser beam converted by the wafer detecting unit corresponds to a second electrical signal, or a distance value will be generated on basis of the optical signal of the received wafer detecting laser beam;
• and
• a detection processing unit, which is electrically connected to the wafer parallel measuring unit and the wafer detecting unit;
• the detection processing unit judges whether the wafer is parallel to the bottom of a clamping jaw on basis of the first electrical signal;
• the detection processing unit judges whether the wafer is clamped by the clamping jaw on basis of the second electrical signal;
• or the detection processing unit judges whether the wafer is clamped by the clamping jaw by comparing the distance value with a preset distance threshold value,
• wherein the wafer detecting unit includes a distance measuring laser sensor located above the wafer.