Test method for temperature evenness of hot plate

Abstract

The invention provides a test method for the temperature evenness of a hot plate, which comprises the following steps: two asymmetric patterns are placed on a photolithographic mask, the distance between the two asymmetric patterns is D1, and the distance between the center lines of the two asymmetric patterns is L1; a PEB (Post Exposure Bake) temperature is set; an exposured round disc with two asymmetric patterns is subjected to PEB, so as to form latent image patterns, wherein the D1 is changed to D2 and the L1 is changed to L2; and the two asymmetric patterns form counterpoint marks or specific test structures of a photolithographic machine, the counterpoint system of the photolithographic machine is utilized to test the coordinates / distance of each counterpoint mark or specific test structure, the difference between the test value and a theoretic value is obtained, so as to quantitatively reflect the temperature evenness of the hot plate. The invention quantitatively reflects the temperature evenness of the hot plate by utilizing the property of shifting of the center positions of the latent image images which are formed in the way that the asymmetric patterns is subjected to PEB.

Description

【Technical field】 [0001] The invention relates to a method for testing the temperature uniformity of a hot plate, in particular to a method for testing the temperature uniformity of a hot plate used in a semiconductor photolithography process. 【Background technique】 [0002] With the development of integrated circuit semiconductor technology, the feature size of the device is getting smaller and smaller, and correspondingly, the online process fluctuation is also required to be reduced. That is, the control specifications for the uniformity and repeatability of each individual process result become more stringent. [0003] In the existing semiconductor lithography process, deep ultraviolet (DUV) lithography process is widely used, which uses a specific chemically amplified photoresist (CAR: Chemically Amplified Photoresist). The characteristic of the deep ultraviolet lithography process is that after the exposure of the lithography machine, it must be baked to complete a co...

AI Technical Summary

Problems solved by technology

[0005] 1. The hand-held temperature test device directly tests the temperature of the hot plate: its disadvantage is that the hot plate bakes the wafers in a relatively closed environment, that is, the shutter used to transport the wafers during baking Must be closed, and when testing, the partition must be opened so that the thermocouple contacts the test temperature through the partition and the hot plate

The disadvantage of this method is that: when testing in wired mode, the clapboard of the hot plate must be opened, which affects the test of temperature uniformity; replace

The disadvantage of this method is that the change of line width is not only affected by the uniformity of the hot plate, but also affected by the development process, so it is impossible to accurately analyze the data to judge the uniformity of the hot plate

Images