Method for determining photoetching exposure defocusing amount

Abstract

The invention discloses a method for determining a photoetching exposure defocusing amount. The method comprises the steps as follows: a Bossung curve of photoresist line widths and a Bossung curve of photoresist line side-wall widths are created, and a first exposure defocusing amount area and a second exposure defocusing amount area are selected from two Bossung curves respectively according to the acceptable photoresist line widths and photoresist morphology; and then, a first defocusing amount is selected in the first exposure defocusing amount area, a second defocusing amount is selected in the second exposure defocusing amount area, an average value of the first defocusing amount and the second defocusing amount is obtained, and the optimum photoetching exposure defocusing amount is obtained. Therefore, with the adoption of the method, on the premise of solving the problem that the line widths is up to the standard but the photoresist morphology is not up to the etching standard when the exposure defocusing amount is determined by the line widths, the optimum photoetching exposure defocusing amount is determined rapidly and accurately, the stability of a photoetching technique is improved, and the yield and the quality of a product are guaranteed.

Description

technical field [0001] The invention relates to the field of semiconductor integrated circuit manufacturing, in particular to a method for determining the defocus amount of photolithography exposure. Background technique [0002] Photolithography is one of the key processes in the manufacture of semiconductor devices and large-scale integrated circuits. Typically, the photolithography process involves coating a semiconductor wafer (or substrate) with a photoresist (or photoresist) layer and using an actinic light source (such as an excimer laser, mercury, etc.) Light, etc.) to expose the photoresist, it must not only have the technical ability to analyze the line width of the characteristic size, but also have the ability to ensure the uniformity and stability of the line width of the characteristic size. Especially in the large-scale production of chips, how to ensure the uniformity and stability of the line width of the feature size is very important for stabilizing the p...

AI Technical Summary

Problems solved by technology

[0005] The object of the present invention is, for above-mentioned problem, proposes a kind of method for determining photolithographic exposure defocus amount, this method is by comprehensive consideration to photoresist line width Bossung curve and photoresist line sidewall width Bossung curve, On the premise of avoiding the problem that the line width meets the standard but the photoresist shape cannot meet the etching when the defocus amount of lithography exposure is determined according to the line width, the optimal defocus amount of lithography exposure can be quickly and accurately determined, To improve the stability of the photolithography process and ensure product yield and quality

Images