Preparation method and failure analysis method for transmission electron microscope (TEM) sample

Abstract

The invention provides a preparation method and failure analysis method for a transmission electron microscope (TEM) sample. The method comprises the following steps: performing rough positioning on a failure area on a substrate, cutting an initial sample comprising the failure area, accurately positioning a specific failure point in the initial sample by using the TEM, and thinning the initial sample to form a final sample, namely the TEM sample for TEM electronic penetration can be provided. Therefore, the technical problems that a focused ion beam (FIB) is insufficient in resolution ratio, a failure point on a specific layer with small enough thickness inside a semiconductor cannot be accurately positioned and a TEM sample cannot be manufactured in the traditional technology are solved.

Description

Technical field [0001] The invention relates to the field of semiconductors, in particular to a method for preparing a TEM sample and a failure analysis method. Background technique [0002] In the semiconductor production process, it is inevitable that there will be problems in the process of forming some semiconductor devices on the substrate, such as uneven film deposition thickness during the deposition process. Therefore, it is necessary to inspect the internal structure of the semiconductor device in real time during the production process to remove the defective device or part of the device and find the cause of the problem to facilitate subsequent production. [0003] At present, the commonly used method is to extract a sample for transmission electron microscopy (TEM) observation from the substrate, and use TEM to observe the cross section of the TEM sample to find the location of the failure point, and the phenomenon caused by the failure location, and carry out the failu...

AI Technical Summary

Problems solved by technology

[0006] However, due to the limitation of the resolution of the FIB machine, when the thickness of a specific layer in a semiconductor device such as an ultra-thin gate oxide layer is too small (for example, less than 3nm), it cannot be observed by the FIB machine, and naturally the specific layer cannot be found abnormal region

In this way, the purpose of extracting TEM samples that contain abnormal areas and can be observed and analyzed by TEM machines in the roughly located failure positions cannot be achieved

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