Exposure method

Abstract

An exposure method comprises the steps: providing a substrate to be graphed; carrying out first exposure of the substrate to be graphed; carrying out re-exposure of the substrate to be graphed after undergoing the first exposure, wherein the re-exposure specific operation comprises the steps of simultaneously rotating a mask and the substrate at a same angle and then carrying out exposure. The exposure method adopts a mode of carrying out multiple exposure by angle conversion, so as to eliminate a shadow effect in an EUV technology, reduce graphic deviation appearing in the exposure, and increase the exposure accuracy.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to an exposure method in extreme ultraviolet lithography technology. Background technique [0002] At present, the entire semiconductor industry is approaching the physical limit of the optical lithography process. In the absence of a specially designed optical lithography process technology, we will need to use next-generation lithography technologies such as extremely short ultraviolet lithography (EUV) , in order to extend the semiconductor process to below the 32nm technology node. [0003] The exposure process of the EUV exposure equipment that has been put into use now is as follows: figure 1 As shown, it includes three stages: the first stage 1 is the emission stage, the extreme ultraviolet light is emitted from the light-emitting device, and projected onto the mask, which has pattern areas and non-pattern areas; the second stage 2 It is the propagation stage. In ...

AI Technical Summary

Problems solved by technology

And because the materials of the graphic area 70 and the non-graphic area on the mask are different, there will be a height difference between the two, even if there is only a few nanometers of height difference, it will also produce such figure 2 The phenomenon shown: the height of the mask pattern 70 blocks the incident light and a shadow effect appears on the mask plate 200, causing the lines of the pattern 71 formed on the silicon wafer 100 to be widened or shifted in the direction perpendicular to the incident light

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