Abstract

A reproducible way to transfer a single crystalline sample into a gas environmental cell holder for in situ transmission electron microscopic (TEM) analysis is shown in this study. As in situ holders have only single-tilt capability, it is necessary to prepare the sample precisely along a specific zone axis. This can be achieved by a very accurate focused ion beam lift-out preparation. We show a step-by-step procedure to prepare the sample and transfer it into the gas environmental cell. The sample material is a GaP/Ga(NAsP)/GaP multi-quantum well structure on Si. Scanning TEM observations prove that it is possible to achieve atomic resolution at very high temperatures in a nitrogen environment of 100,000 Pa.

Impact Statement

Focused ion beam (FIB) sample preparation is an important technique for TEM analysis of bulk materials, including single crystal samples. Closed cell holders are single tilt, so the ability to tilt to a zone axis is limited. A method to create FIB samples compatible with the Atmosphere gas cell is described, including a method to precisely orient single crystal samples, so high resolution STEM images are achieved.