Patent ID: 11862457
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  B | IPC B  H

Claim 12:
13. A method of fabricating a semiconductor device, the method comprising:
disposing a wafer on a chuck;
irradiating a lower surface of the wafer with a laser to heat the wafer; and
supplying a chemical to an upper surface of the wafer to clean the wafer,
wherein the laser penetrates an optical system including a lens array,
wherein the laser penetrates a calibration window which includes a light projection window including a lower surface, a first coating layer having a first light transmissivity on the lower surface of the light projection window, and a second coating layer having a second light transmissivity greater than the first light transmissivity on the lower surface of the light projection window, and
wherein the second coating layer includes first to third sub-coating layers which are sequentially stacked on the lower surface of the light projection window, and refractive indexes of the first to third sub-coating layers decreases in a direction receding from the lower surface of the light projection window.