Characterization of the electrical properties and thickness of thin epitaxial semiconductor layers by THz reflection spectroscopy
- 1 December 2001
- journal article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 90 (11) , 5778-5781
- https://doi.org/10.1063/1.1412574
Abstract
We have measured the dielectric properties and thickness of thin semiconductor epitaxy layers by the reflection of THz radiation from the surface of a two-layered semiconductor wafer. When reflecting from two interfaces the electromagnetic pulse has a destructive interference at a specific wavelength dependent on the thickness of the outer layer and its dielectric function. Near that frequency the reflection coefficient has a significant drop. By extending the incident pulse spectrum to include this interference frequency, a measurement of the thickness can be obtained together with a direct measurement of the carrier number density. By this technique epitaxy layers of thickness down to 15 μm are characterized.This publication has 12 references indexed in Scilit:
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