Method for manufacturing phase shift photomask

Abstract

The invention provides a method for manufacturing a phase shift photomask. The method comprises the following steps of: forming a first layout graphics structure in a first photoresist in a first photoetching way on a phase shift photomask substrate comprising the first photoresist capable of forming a hard film; coating a micro auxiliary film on the first photoresist to cure the first layout graphics structure in the first photoresist, performing heating to react the micro auxiliary film and the surface of the first photoresist to form a separation film insoluble in a second photoresist, and removing a redundant micro auxiliary film by using de-ionized water or the de-ionized water solution of a surfactant; coating the second photoresist on the cured first photoresist; performing second photoetching, thereby forming a second layout graphics structure in a second photoresist film; and performing etching to transfer the first and second layout graphics structures in the photoresists into a partially transparent molybdenum silicide thin film and a non-transparent chromium thin film respectively to finish manufacturing the phase shift photomask. According to the method, the etching step of a phase shift photomask manufacturing process is eliminated, so that yield can be effectively improved, and manufacture cost can be reduced.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, and more specifically, the invention relates to a method for manufacturing a phase shift photomask. Background technique [0002] Photolithography is one of the key processes for making large-scale integrated circuits. The photolithography process is to transfer the layout pattern on the photomask to the photoresist film, and the photoresist film containing the layout pattern is used as a mask for the subsequent ion implantation or etching process. Photomasks play an important role in the photolithography process. With the continuous improvement of the integration level of semiconductor chips and the continuous reduction of the feature size of transistors, the requirements for photolithography technology are getting higher and higher, and phase shift photomasks have gradually become the mainstream photomasks of high-end photolithography technology. [0003] Such as Figure 1A As shown...

AI Technical Summary

Problems solved by technology

[0007] However, the steps of the phase-shift photomask manufacturing process according to the prior art are still not simplified enough

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