Method for testing linewidth uniformity

Abstract

The invention relates a method for testing linewidth uniformity. The method comprises the following steps of 1, preparing k linewidth testing figures of which desired values are linewidth design values on a lithographic plate, 2, testing linewidth actual values of all the k linewidth testing figures on the lithographic plate, 3, calculating k differences between the linewidth actual values of the k linewidth testing figures and the corresponding desired values, 4, carrying out photoetching of the k linewidth testing figures on a disk, 5, testing linewidth real values of the k linewidth testing figures on the disk, 6, calculating mask error enhancement factor (MEEF) verification values according to the desired values or the linewidth actual values as linewidth values of the k linewidth testing figures, and the linewidth real values, 7, respectively calculating the product of the k differences and the MEEF verification values so that k corresponding compensation values are obtained, and 8, calculating the sum of the linewidth real values of the k linewidth testing figures and the k corresponding compensation values so that k linewidth final values are obtained, wherein the k linewidth final values are utilized as linewidth uniformity evaluation data. The method provided by the invention has the advantage that plate making error compensation values are obtained by MEEF verification value calculation so that a plate making error is avoided.

Description

【Technical field】 [0001] The invention relates to a semiconductor process, in particular to a test method for line width uniformity used for performance evaluation of a lithography machine lens. 【Background technique】 [0002] The single imaging area on the wafer after the photolithography pattern is exposed through the lens of the lithography machine is called a shot. The uniformity of line width in each shot on the wafer is an important parameter of the lithography process, especially the shot size is lithography The uniformity of line width at the maximum available range of the machine lens is a key indicator for evaluating lithography machines. [0003] The traditional evaluation method is to repeatedly place some line width test patterns on the photolithography plate, test the line width after exposure on the wafer, and obtain the line width uniformity within shot (within shot, WIS). figure 1 It is a flow chart of the traditional test method of line width uniformity. ...

AI Technical Summary

Problems solved by technology

However, due to the influence of the lithography plate manufacturing process, the line width of the repeated test patterns in each area on the final lithography plate is inconsistent, so the measured line width uniformity will be affected by the error of the lithography plate making, that is to say, it will Affected by the joint effect of lithography plate making and lithography machine lens, it cannot truly reflect the performance of lithography machine lens

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