The characterization of wafer surfaces and interfaces using high‐frequency phonons

Abstract

AbstractWe show that the scattering of nanosecond heat pulses can be used to characterize the surface quality of single crystal wafers for device applications. The technique is sensitive because the high‐frequency phonons that make up the heat pulses have wavelengths that are comparable with the typical scale of surface imperfection. The advantages of the technique are that it is non‐destructive, can be applied to both semiconductors and insulators, requires minimal preparation and can be used to observe deep subsurface structure.