Use of cleaved wedge geometry for plan-view transmission electron microscopy sample preparation

Abstract

A fast, convenient, and easy to perform method for preparing plan-view transmission electron microscopy (TEM) specimens of brittle materials is proposed. The method is ideal for thin films/coatings and based on obtaining wedge-shape geometries of the samples via conventional cutting and cleaving followed by gentle focused ion beam (FIB) milling to electron transparency. It enables multiple parallel windows for depth sectioning of the samples and facilitates FIB lift-out procedure. The method has been successfully applied for preparing high-quality plan-view TEM samples for a range of films deposited on Si, SiC, and Al2O3 which significantly enhances throughput and reduces time at the FIB. The method further offers high success rate even for the novice, stable handling and reproducibility, which greatly widens the application of advanced plan-view TEM studies in material science.