Contact/proximity stepper using UVA, UVB, and UVC light sources

摘要

Novel wafer stepper by using contact or proximity printing was developed. The ultraviolet region starts right after the violet end of the rainbow. In scientific terms, UV radiation is electromagnetic radiation just like visible light, radar signals and radio broadcast signals. Ultraviolet radiation can be broken down into three bands: UVA, UVB, and UVC. Projection wafer stepper needs use single wavelength as light sources, such as: g-line, i-line, KrF and ArF. The broadband wavelengths of the UVA, UVB and UVC regions: UVA 400 nm - 315 nm, UVB 315 nm - 280 nm, UVC 280 nm - 100 nm can be used for contact or proximity exposure. Wafer stepper without using projection lens, system reliability and manufacturing cost of wafer stepper can be improved by using contact/ proximity method. This novel contact/ proximity wafer stepper can be used for 3DIC, MEMS and bio-chip lithography application by using thin and thick resist.