Evaluation of diamond-ground beveled surfaces with Hg gate capacitance–voltage and current–voltage

Abstract
The spreading resistance profiling (SRP) method has undergone significant improvements over the last five years, enhancing the techniques’ capability for profiling sub-100 nm junctions. Newly developed procedures for conditioning probes, preparing beveled surfaces, and processing the raw data now yield a high degree of success. We believe that the sample preparation technique determines the quality of the bevel surface and thus plays a key role in the repeatability and sensitivity of SRP measurements. Although some previous work has suggested that the diamond ground beveled surfaces used for these measurements involve significant surface damage and hence, a high surface state density, little work has been done to quantify bevel surface quality. In this article, Hg gate capacitance–voltage (C–V) and current–voltage (I–V) have been used for the first time to determine the electrical properties of the diamond-beveled surfaces. Diamond particle sizes ranging from 0.05 to 0.25 μm were used to bevel p silicon samples. Measurements were made on both the diamond-ground bevels and on the original top surface of the sample chips using a mercury probe and several defect sensitive C–V and I–V measurements such as Schottky C–V and forward and reverse I–V. The three major surface quality factors that are investigated are surface leakage, interface and near surface bulk trap density, and surface roughness.