Theoretical Modeling of Linear Absorption Coefficients in Si/Si1-xGex Multiple Quantum Well Photodetectors

Author

Kevin D. Greene

Date of Award

12-1996

Document Type

Thesis

Degree Name

Master of Science

Department

Department of Engineering Physics

First Advisor

David E. Weeks, PhD

Abstract

Si/Si_1-xGe_x MQW Infrared Photodetectors offer the promise of normal incidence photodetection tunable over the range of 3-12 micrometers wavelength range at temperatures above 40 K. This system is attractive because the Si_1-xGe_x offers greater compatibility with existing Si based signal processing circuitry. Band structures, momentum matrix elements and linear absorption coefficients are computed using a Luftinger-Kohn k/p analysis for Si/Si_1-xGe_x quantum wells grown in the 110 direction. The absorption coefficient as a function of energy and wavelength is calculated by two methods: a delta function fit to intersubband transitions, and a Lorentzian fit to intersubband transitions. Calculations were performed for parallel as well as normally incident radiation and the resulting absorption spectra are in good agreement with experimental observations.

AFIT Designator

AFIT-ENP-GAP-96D-06

DTIC Accession Number

ADA324907

Recommended Citation

Greene, Kevin D., "Theoretical Modeling of Linear Absorption Coefficients in Si/Si1-xGex Multiple Quantum Well Photodetectors" (1996). Theses and Dissertations. 5837.
https://scholar.afit.edu/etd/5837