ABSTRACT
Sample preparation is known to have a major effect on phase contrast recorded from a doped semiconductor sample using electron holography [I, 2]. Focused ion beam (FIB) milling is a particularly attractive sample preparation technique as it provides the sitespecificity required for characterising future device generations. However, the effect on the electrostatic potential in the sample of the physical damage and Ga implantation associated with this technique [3] must be assessed before holograms obtained from FIB-prepared semiconductors can be interpreted with confidence. In comparison to FIB milling, cleaving provides specimen surfaces undamaged by ion beam milling, which may be crystallographically defined. Furthermore, small-angle cleaving allows wedgeshaped samples with shallow thickness profiles to be prepared. Here, we address the effect of sample preparation using FIB milling and small-angle cleaving on the contrast recorded from a silicon p-n junction, which is examined with and without an applied reverse bias.
