Monitoring Method of Scattered Light Parameters of Exposure Machine

Abstract

The invention provides a monitoring method for a scattered light parameter of an exposure machine. The monitoring method at least comprises the following steps of S1, providing a first control wafer, forming a first positive photoresist layer on the first control wafer and developing, and measuring to obtain a thickness T1; S2, providing an optical cover and a second control wafer, forming a second positive photoresist layer on the second control wafer, carrying out multiple exposure and developing by using the optical cover, and drawing a curve by taking exposure energy as horizontal coordinates and the thickness of the residual second positive photoresist layer in an illumination region as vertical coordinates to obtain a slope S; S3, providing a third control wafer, forming a third positive photoresist layer on the third control wafer, exposing under predetermined exposure energy E by using the optical cover, and measuring the thickness T2 of the third positive photoresist layer arranged in a non-illumination region after developing; and S4, calculating to obtain the scattered light parameter F according to a formula of F=(T1-T2) / (E*|S|)*100%. By the monitoring method, off-line monitoring on the scattered light parameter F of the exposure machine can be achieved at any time, the period is greatly shortened, thus, the imaging quality of the exposure machine is ensured in real time, and product yield is improved.

Description

technical field

[0001] The invention belongs to the field of semiconductor manufacturing and relates to a monitoring method for scattered light parameters of an exposure machine. Background technique

[0002] An exposure machine refers to a device that transfers image information on a film or other transparent body to a surface coated with a photosensitive substance by turning on the light to emit ultraviolet rays of UVA wavelength. In photolithography technology, a photolithography exposure machine generally includes a light source, a mask plate and a lens. A mask is a glass plate whose surface is covered with various patterns, each pattern containing opaque and transparent parts that block and allow light to pass through. The light source can project the pattern onto the wafer coated with photoresist through the mask plate to generate a three-dimensional relief pattern, which is used to assist in etching circuit patterns on the wafer.

[0003] The most commonly used expo...

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