Photoetching system mask proximity effect correction method

Abstract

A mask proximity effect correction method for a lithography system. First, find out the distortion of the final pattern on the silicon wafer compared with the mask design pattern, and correct it according to the proximity effect at the corresponding position of the mask pattern according to the position of the distorted pattern. The method to pre-segment and add the mask graphics: add serifs at the junction of X and Y graphics, and add non-transparent proximity effect correction graphics with 180-degree phase shift on both sides of the serifs, together Constitute the preliminary framework of phase-shift proximity effect correction; then observe the exposure result after adding phase-shift proximity effect correction through lithography simulation method, and according to the exposure result, use simulation software to measure the error between the exposure result and the expected pattern, according to This error adjusts the size, transmittance and other related parameters of the phase-shift proximity effect correction on the reticle until the error between the developed pattern on the silicon wafer and the original design pattern of the reticle is less than the allowable limit of ±10% deviation in industrial lithography .

Description

technical field [0001] The invention relates to a mask proximity effect correction method for a photolithography system, in particular to a mask proximity effect correction method for 65nm and below nodes in an ArF photolithography system. Background technique [0002] The resolution of optical lithography is gradually improving. With the gradual reduction of lithographic feature size, the proximity effect is more obvious. However, the traditional proximity effect correction has insufficient correction accuracy or cannot meet the requirements in some graphic structure applications. . Taking the T-shaped graph structure as an example, the X-direction graph has obvious line-end shortening effect, and the traditional proximity effect correction method cannot meet the requirements in terms of correction accuracy and spatial size, and a new proximity effect correction method is urgently needed. [0003] At present, in order to improve the imaging resolution of similar patterns s...

AI Technical Summary

Problems solved by technology

[0011] The technical problem to be solved in the present invention is: to overcome the deficiencies of mask layout in some IC designs, such as the graphic couplets and strong phase shift mask technology caused by the simultaneous presence of X and Y graphics, which cannot be applied, and propose a mask graphic Proximity effect correction method, the invention improves the fidelity of graphic imaging by adding phase-shifting proximity effect, especially the mask of 65nm and below nodes in the ArF lithography system

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