Effect of Si-Ge interdiffusion on the waveguide properties of SiGe-Si MQW photodetector

Author

Zhu, Yuqing ; Yang, Qinqing ; Wang, Qiming

Author_Institution

Nat. Integrated Optoelectron. Lab., Acad. Sinica, Beijing, China

Volume

33

Issue

5

fYear

1997

fDate

5/1/1997 12:00:00 AM

Firstpage

761

Lastpage

764

Abstract

Because of Si-Ge interdiffusion in the Si-SiGe interface during the growth process, the square-wave refractive index distribution of a SiGe-Si multiple-quantum-well (MQW) will become smooth. In order to simulate the actual refractive index profile, a staircase approximation is applied. Based on this approach, the dispersion equation of the MQW waveguide is obtained by using a transfer matrix method. The effects of index changes caused by the interdiffusion on the optical field and the characteristics of the photodetector are evaluated by solving the dispersion equation. It is shown that the Si-Ge interdiffusion can result in a reduction of the effective absorption coefficient and the quantum efficiency

Keywords

Ge-Si alloys; absorption coefficients; chemical interdiffusion; optical dispersion; optical waveguide theory; photodetectors; refractive index; semiconductor materials; semiconductor quantum wells; silicon; Si-Ge interdiffusion; SiGe-Si; SiGe-Si MQW photodetector; dispersion equation; effective absorption coefficient; growth process; optical field; photodetector characteristics; quantum efficiency; refractive index profile; semiconductor waveguide; square-wave refractive index distribution; staircase approximation; transfer matrix method; waveguide properties; Absorption; Dispersion; Equations; Optical refraction; Optical variables control; Optical waveguides; Photodetectors; Quantum well devices; Refractive index; Transmission line matrix methods;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/3.572150

Filename

572150