TEM sample preparation method

A TEM sample preparation method comprising:

• placing a sample including an observation target therein on a sample holder so that a first side surface of the thin sample, which is closer to the desired observation target than a second side surface of the sample is to the observation target, is opposed to a focused ion beam column;
• setting a processing region, which is to be subjected to etching processing by a focused ion beam, to a region of the first side surface;
• and
• performing etching processing to a portion of the sample extending from the first side surface thereof to a front surface thereof by irradiating the processing region with the focused ion beam from the focused ion beam column, thereby forming a film portion including the observation target and having a thickness direction substantially parallel to a thickness direction of the sample,
• wherein the processing region includes a first irradiation region at the front surface side thereof and a second irradiation region at the film portion side thereof, and
• wherein an irradiation amount of the focused ion beam is set to be larger in the second irradiation region than in the first irradiation region.

A TEM sample preparation method comprising:

• providing a sample having opposed front and rear surfaces bounded by side surfaces and having inside thereof a desired observation target;
• placing the sample on a sample holder so that one side surface of the sample that is closest to the observation target is opposed to a focused ion beam column;
• setting a processing region, which is to be subjected to etching processing, to a region of the one side surface of the sample, the processing region having two inner irradiation regions sandwiching therebetween a portion of the sample that has the observation target, and two outer irradiation regions, one extending from the front surface to one of the inner irradiation regions and the other extending from the rear surface to the other of the inner irradiation regions;
• and
• performing etching processing of the sample by irradiating the processing region with a focused ion beam from the focused ion beam column to form a TEM sample containing the observation target, the irradiation amount of the focused ion beam being larger when etching processing in the inner irradiation regions than when etching processing in the outer irradiation regions.