Exposure system and exposure method for semiconductor photolithography

Abstract

An exposure system and an exposure method. The method comprises: arranging a micro-reflector array (4) between a uniform light unit (3) and a reflector (5) to replace a variable slit apparatus; according to the pattern of a mask plate (7) during exposure and the requirements for exposure precision, setting parameters of an exposure field of view; and inputting same into drive software of the micro-reflector array (4), so as to calculate motion parameters of the micro-reflector array (4) during the exposure. During the exposure, a control card continuously sends an instruction to each digital micro-mirror in the micro-reflector according to data in the drive software, and each digital micro-mirror takes a corresponding flipping action each time the instruction is received until the exposure ends. The micro-reflector array (4) has thousands of digital micro-mirrors, so that the exposure field of view, range and dose are changed in real time, thereby avoiding the mechanical vibration generated by a traditional variable slit apparatus when changing the shape of the slit and the requirements for the high acceleration of a slit apparatus drive system, and reducing the complexity of an exposure system mechanical structure and a control system.

Description

technical field [0001] The invention relates to the field of semiconductor lithography, in particular to an exposure system and an exposure method for semiconductor lithography. Background technique [0002] In the semiconductor IC integrated circuit manufacturing process, a complete chip usually needs to undergo multiple lithography exposures to complete, and the mask used for each lithography and process requirements will change. When the process requirements are high , the light intensity needs to be concentrated and the stray light needs to be blocked. When the pattern area of ​​the mask is complex, the invalid stray light in some areas also needs to be blocked to ensure the accuracy of the pattern left on the silicon wafer after exposure. However, when the process requirements are relatively low, or the graphic area is relatively simple, and the lithography precision requirements are low, the part of the stray light with low light intensity generated by the illumination...

AI Technical Summary

Problems solved by technology

[0003] The traditional variable slit is realized by the high-speed and high-acceleration motion of the knife-edge mechanical structure. It is necessary to design a physical motion with a high acceleration of 5-10G in the exposure system, which introduces a large dynamic disturbance to the precise optical system and affects the final lighting performance

At the same time, in order to realize the correction of non-scanning and high-order dose errors in the field, the variable slit of the traditional structure needs to make nearly 20 pairs of programmable micro-motion structures on the knife edge, resulting in an extremely complex system structure, and the variable slit It is a mechanical device, which will inevitably produce vibration and shock during the change process, and the change also requires the driving system of the variable slit to have a high acceleration function, which makes the engineering feasibility and reliability of the entire exposure system low

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