Critical Thickness for Semiconductor Specimens Prepared using Focused Ion Beam Milling

Abstract

The electrostatic potential distribution in FIB-prepared membranes containing a silicon p-n junction has been examined using off-axis electron holography and electron tomography. The experimentally determined 3-D electrostatic potential was examined to quantify the variation in the electrostatic properties of the device as a function of distance from the specimen surfaces. It was found that specimen preparation using a 30 kV Ga ion beam alters the electrical properties of the membrane to a depth of 175 nm from the specimen Surfaces.