Method for preparing transmission electron microscopy (TEM) sample

Abstract

The invention relates to the technical field of semiconductor manufacturing, and in particular relates to a method for preparing a transmission electron microscopy (TEM) sample. The method comprises the steps of acquiring the position of a failure point of a failure chip and the position of a failure analysis reference point of a non-failure chip, polishing the failure chip to the part near the failure point along the direction vertical to a selected side, and polishing the non-failure chip to the part near the failure analysis reference point along the direction vertical to the selected side; sticking the front of the failure chip and the front of the non-failure chip together to form a structure to be tested; and putting the structure to be tested into a focused ion beam (FIB) machine with the polished surface being upward to prepare the TEM sample. Therefore, the TEM sample can be rapidly prepared; the most appropriate thickness can be found out when a picture with high resolution is shot, so that the quality of the picture with high resolution can be guaranteed.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for preparing TEM samples. Background technique [0002] At present, transmission electron microscopy (TEM) is an important tool in electron microscopy, and TEM can be used to detect the morphology, size and characteristics of thin films that make up semiconductor devices. After the TEM sample is placed in the TEM observation room, the main working principle of the TEM is: when the high-energy electron beam penetrates the TEM sample, phenomena such as scattering, absorption, interference, and diffraction occur, so that a contrast is formed on the imaging plane, thereby forming an image of the TEM sample , followed by observation, measurement and analysis of the image of the TEM sample. [0003] In the prior art, the focused ion beam (FIB) machine can complete the preparation of TEM samples in a local area of ​​the entire wafer. In the process of usin...

AI Technical Summary

Problems solved by technology

However, for the preparation of ultra-high-height samples that need to take pictures of multi-layer structures with a thickness of more than 3 microns, it is necessary to roughly dig a large deep pit from the chip surface to form a marking pit, and the subsequent thinning cannot be less than 2 µm. The digging depth is twice as much as the preparation of general TEM samples, and the whole process will be very laborious and time-consuming

Moreover, the prepared samples are often not perfect due to insufficient uniformity of the ion beam, which is undesirable for those skilled in the art

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