Method for Preparing TEM Sample

The present application discloses a method for preparing a TEM sample, comprising: step 1, step 1, providing a chip sample having a metal protective layer formed on a first surface; step 2, fixing the chip sample on a sample table of a FIB system; step 3, performing the first time of FIB cutting on the metal protective layer along a first direction, so as to form a groove, wherein the first direction is the width direction of the TEM sample, and the inner side surface of the groove is arc-shaped so that the thickness of the metal protective layer in a groove area gradually changes; and step 4, performing the second time of FIB cutting along a third direction to thin the chip sample and form the TEM sample, wherein the third direction is a direction from the metal protective layer to the chip sample.