Method for reducing overheating of lithography machine lens

Abstract

The invention discloses a method for reducing overheating of lithography machine lenses. The method comprises the following steps of: calculating the ratio A of the pervious light area to the whole exposure unit area on condition that the distance to an effective device is larger than or equal to D, and adding redundancy graphs at an open area according to the ratio relationship of A, wherein the distance from the open area to the effective device is larger than or equal to D. The method for reducing the overheating of the lithography machine lenses has the beneficial effects of reducing the energy absorbed by the lithography machine lens and decreasing the lens temperature raised by continuous exposure, thereby realizing control to position offset of exposed graphs on a silicon wafer caused by the overheating of the lithography machine lenses.

Description

technical field [0001] The invention relates to a method for adjusting the temperature of the lens of a photolithography machine, in particular to a method for reducing the overheating of the lens of a photolithography machine based on reducing the specific gravity of the light-transmitting area on the mask. Background technique [0002] In the integrated circuit manufacturing process, the pattern on the mask plate is usually transferred to the silicon wafer by exposing it to a laser with a specific wavelength. For some layers with a particularly large proportion of the light-transmitting area on the mask, the energy of the light passing through the lens of the photolithography machine is also relatively large. At the same time, since the lens of the lithography machine will also absorb part of the energy of the transmitted light, after a long period of continuous exposure, the temperature of the lens of the lithography machine will increase significantly, which will cause a...

AI Technical Summary

Problems solved by technology

At the same time, since the lens of the lithography machine will also absorb part of the energy of the transmitted light, after a long period of continuous exposure, the temperature of the lens of the lithography machine will increase significantly, which will cause a slight deformation of the lens of the lithography machine, and eventually As a result, the position of the graphics exposed on the silicon wafer has shifted, and in serious cases, the subsequent overlay accuracy inspection will exceed the standard

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