A FIB Micro-Sampling Technique and a Site Specific TEM Specimen Preparation Method

Abstract

A FIB micro-sampling technique has been developed to facilitate TEM specimen preparation while allowing samples to remain intact. A deep trench is FIB-milled to remove a portion of the sample containing the region of interest. A micromanipulator is employed for the purpose of lifting out a small portion of the sample, i.e., the micro-sample. FIB assisted metal deposition is used to bond the micro-sample to the micromanipulator. The micro-sample is subsequently lifted out and mounted onto an edge of the micro-sample carrier using FIB assisted metal deposition. The micro-sample is then thinned to the thickness of about 0.1µm for TEM observation. All of the above steps are accomplished under vacuum in the same FIB system. This procedure is a reliable TEM specimen preparation technique when the evaluation or failure analysis of a specific site is required. Both cross sectional and plan view TEM specimen preparations are feasible with this technique. In addition, a technique to prepare TEM specimens from a specific site has also been developed. In this technique, an FIB system equipped with a FIB/TEM(STEM) compatible specimen holder is used for thinning of the samples, e.g., a micro-sample. The compatible specimen holder permits repeated alternating FIB milling and TEM(STEM) observation, enabling TEM specimen preparation from a specific site.