In this paper, the 1 066 nm fiber laser wafer identification system is used to carry out the research of wafer identification process. The duty ratio and pulse width are respectively changed by the control variable method to mark SEMI T7 code on the wafer. The Dot morphology is observed by the digital microscopic system, and the code reader is used for reading test. Results show that there was a wide process window for 1 066 nm laser identification wafer, and the Dot morphology was smooth and spatter free in the duty ratio range of 10%~22%. The pulse width has a great influence on the Dot morphology, but it has little influence on the read time after the hardware and software processing and optimization of the reader. Within the duty ratio of 10%~22% and pulse width of 100~300 ns, no splash, uniform identification can be obtained, which meets the SEMI identification requirements.