Method for detecting failure dapth of deep channel

Abstract

The method includes steps: preparing specimen, and obtaining position of ineffective deep groove in the sample; when rotating specimen stage for focusing ion beam to prearranged angle; the method uses ion beam perpendicular to surface of specimen to cut out drop pit at prearranged distance on one side of the deep groove; rotating specimen stage for focusing ion beam, the method uses ion beam inclined a prearranged angle with surface of the specimen to cut specimen including specimen with ineffective deep groove; and using electron beam inclined a prearranged angle with surface of the specimen to observing image at top of the ineffective deep groove. The invention saves time for analyzing ineffective depth of deep groove; raises analytical accuracy, and success ratio.

Description

technical field [0001] The invention relates to the analysis and detection technology in the integrated circuit manufacturing process, in particular to a method for measuring the failure depth of deep grooves. Background technique [0002] In recent years, with the development of semiconductor manufacturing process, cross-sectional structure has more and more influence on the yield and reliability of high-end devices. For example, in a deep trench (Deep Trench, DT), the shape and size of sidewalls are key factors affecting the performance of semiconductor devices. [0003] In order to improve the quality of the deep groove machining process, it is necessary to analyze the position of the failed deep groove and the failure depth of the failed groove, and feed back the data obtained from the analysis to the production department. This is because the processing of deep grooves usually needs to be divided into multiple stages, and the process conditions of each stage (such as g...

AI Technical Summary

Problems solved by technology

[0012] Secondly, the analysis performed by this prior art method is not easy to succeed

This is because the overall width of the deep groove is about 100nm, and the ion beam moves about 5nm at a time, so the phenomenon that the failure part is often cut off during cutting, so that the failure depth cannot be accurately measured and analyzed

Moreover, the overall depth of the deep groove is about 8um, and it is difficult to control the collimation of the ion beam during the downward cutting process, resulting in uneven cut sections, which affect the analysis of the cross-sectional views

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