Dynamic measurements of damage generation in single crystal silicon due to sliding contact with a spherical diamond

Abstract

Single or multiple linear unidirectional scratches were made on (111) n-type single crystal silicon surfaces, at room temperature, by a dead-loaded spherical diamond indenter translated in the [110] direction at a speed of 5 cm −1. The damage was measured with a simulated four-point probe technique consisting of a voltage detector designed and fabricated on the silicon wafer. The scratches were made between four electrical pads of the detector through which the electrical resistance of the damage region can be recorded in real time by a data acquisition system. The relative change in voltage, between 3 and 10%, was correlated to the time for the diamond to move past the probes and depended on dead load on the diamond, and the silicon properties. This measurement technique is used to develop a model for subsurface crack generation and propagation. If subsurface damage is modeled as a Hertzian crack then a measure of the voltage provides an estimate of the crack size. This relationship between the measured relative change in voltage and load on a pyramid diamond can be expressed as M(%) αP 4 3 .