Method for measuring double-laser interferometer intersection angle non-orthogonality

Abstract

The invention is concerned with the method that measures the corner nonorthogonal of the two laser interferometer: measures the special marker location on the covering film by a special measure system, and compute the corner nonorthogonal value of the two laser interferometer; the measure system includes: the lighting system, the covering film desk for placing the special covering film, the optical system using for the covering film image, the work desk, the image sensor setting on the work desk, the X and Y direction two laser interferometer. The method is: the laser interferometer records the location of the current work desk after the covering film marker on the special covering film levels with the corresponding marker of the image sensor on the work desk; repeats the above process until all the marker level; uses the two laser interferometer to measure the data modeling, and gets the nonorthogonal value of the two laser interferometer. The invention is: reduces the measure time, predigests the measure process, achieves the automatic measure adjustment of the system periodicity, thereby improves the produce yield and precision of the CMOS chip.

Description

technical field [0001] The invention relates to a photolithography machine in the field of integrated circuit manufacturing, and relates to a method for measuring the non-orthogonality of the intersection angle of two laser interferometers. Background technique [0002] The lithography machine is the most critical equipment in the integrated circuit manufacturing process. Modern photolithography equipment uses optical systems to accurately project and expose the pattern on the reticle to the silicon wafer coated with photoresist. In order to enable chip manufacturing to achieve higher performance at a lower cost, the lithography machine must be more accurate and faster. [0003] The lithography machine relies on two sets of laser interferometers (IFM), which are respectively used for X and Y positioning of the mask table and the workpiece table carrying the silicon wafer. Each group of laser interferometers (IFMs) is composed of two laser interferometers (IFMs) whose emiss...

AI Technical Summary

Problems solved by technology

[0009] The above method does not need to be equipped with additional hardware, but the relative measurement needs to expose the silicon wafer, which takes a long time and seriously affects the productivity of integrated circuit manufacturing

In addition, its testing process is relatively complicated, and it has higher requirements on the performance of other components of the lithography machine

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