193nm fused quartz grating polarizer and application thereof to photoetching equipment

Abstract

The invention relates to a 193nm fused quartz grating polarizer and application of the 193nm fused quartz grating polarizer to photoetching equipment. The grating polarizer is characterized in that a grating with a certain pattern is etched on the surface of a fused quartz sheet, the grating is a sub-wavelength period deep-etching grating, and the linear density of the grating is 5260-5400 lines per millimeter, the depth is 1.1 Mum-1.2 Mum, and the duty ratio is 30%-40%. According to the fused quartz grating polarizer, the grating is directly manufactured on an ultraviolet transmitting optical sheet, so that the energy loss is effectively avoided, and the stability of an optical element is improved. The processing technology is mature, the precision is high, and the cost of the polarizer is effectively lowered. The polarization purity of polarization light is high due to the adoption of the fused quartz grating polarizer. In addition, compared with a multi-film polarizer, the grating is not sensitive to the incidence direction of a light beam, the mechanical alignment precision requirement is low, and the 193nm fused quartz grating polarizer is easy to implement. The grating polarizer is small in thickness and occupied space and can be placed in multiple positions of a photoetching lighting system, and the position selection is more flexible.

Description

technical field [0001] The invention relates to 193nm lithography equipment, in particular to a 193nm fused silica grating polarizer for 193nm immersion lithography equipment to generate required polarization state and its application in the lithography equipment. Background technique [0002] In 193nm immersion lithography equipment, polarized illumination has become an indispensable lithography resolution enhancement technology to improve the resolution of the lithography system, increase the depth of focus and improve the contrast of lithography. The main purpose of using polarized illumination is to achieve contrast enhancement of the interference superimposed light field of the diffracted beam generated by the mask on the illumination light field on the silicon wafer. For high numerical aperture immersion lithography equipment, polarized illumination is particularly important. [0003] At present, the polarization states of the illumination light field of 193nm immersi...

AI Technical Summary

Problems solved by technology

When the metal wire array interacts with deep ultraviolet light, the free electrons in the metal will oscillate under the induction of the photoelectric field, and collisions between electrons and lattice atoms occur, and part of the light energy is converted into heat energy generated by the collision, so the transmitted light intensity There is energy loss and low efficiency

In addition, the crystal lattices of the substrate and the grating array material are not completely matched, so the stability of the device is slightly poor.

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