Fabrication of continuous relief mask for diffractive plane focus lens

The fabrication technology of continuous relief mask for diffractive plane focus lens is studied in the paper. According to Kirchhoff’s scalar diffraction theory, with the ray tracing method, a continuous relief mask for diffractive focus lens has been designed. Using the technology, some experiments on the writing of the mask were carried out with the help of CLWS300M/C. The results show that the laser energy, prebake temperature, developer concentration and preexposure will affect the microstructure of the mask.The mask was fabricated with such technology after a lot of efforts. Compared with the technology for binary optical mask, the technology has the following strong points: process simplification, short period of fabrication and easy operation.