Subsurface Damage Profiling System for Semiconductor Material

摘要

Subsurface damage in polished GaAs wafers has been identified by electron microscopy and other surface analytical techniques. Subsurface damage can adversely affect the performance and reliability of devices fabricated on such substrates. In this report, we introduce a method for determining the degree of subsurface damage as a function of depth. Interferometry is used to measure the rate at which substrate material is being etched from the sample. Measuring the etch rate as a function of depth reveals the profile of subsurface damage in the sample. We describe the methodology and present our findings on GaAs wafers that have been subjected to surface damage. Samples obtained from different wafer manufacturers were investigated. Damage profile, Gallium arsenide, Subsurface damage. (jes)