Accession Number : ADA292464

Title :   Optoelectronics Based on SiGe/Si Heterostructures.

Descriptive Note : Final technical rept. 15 Jul 91-14 Oct 94,

Corporate Author : CALIFORNIA UNIV LOS ANGELES DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Wang, Kang L.

PDF Url : ADA292464

Report Date : 17 FEB 1995

Pagination or Media Count : 35

Abstract : The overall objective of the research was to explore SiGe/Si heterostructures for optoelectronics applications. We have extensively investigated intersubband transitions of Si/Ge quantum structures including p-type Si quantum well, n-type Si(110) quantum wells, and n-type Ge(001) quantum wells. We have also studied many-body effects on the intersubband transitions. The application of these transitions for the fabrication of tunable normal incidence infrared detectors has been demonstrated. In the area of optical properties, we have also demonstrated a large Stark shift in type II SiGe/Si multiple quantum wells and luminescence from Si(sub m)Ge(sub n) superlattices. In the area of transport properties, we have studied the in-plane mobility of coupled delta doped quantum wells as a function of spacing between the wells. An enhancement of hole mobility above that of the Si was found due to the penetration of wavefunctions into the spacer where the impurity scattering is minimal. In addition to exploration of new devices, alternative growth techniques for achieving the layer thickness to the monolayer scale and doping control were also investigated. In the area of the growth control of SiGe epitaxial layers, we have constructed a gas source molecular beam epitaxy 5 stem. We have investigated the orientation dependence of as beam epitaxy. Selective epitaxy growth on SiO2-masked substrates has been demonstrated. We have also studied the role of surfactants for obtaining high quality coherently strained SiGe epitaxial layers and for providing doping control in quantum wells an superlattices. jg

Descriptors :   *ELECTROOPTICS, *QUANTUM WELLS, *SILICON, *GERMANIUM, SCATTERING, LAYERS, QUANTUM THEORY, STRUCTURES, SUPERLATTICES, ORIENTATION(DIRECTION), EPITAXIAL GROWTH, IMPURITIES, TRANSPORT PROPERTIES, PENETRATION, SHIFTING, INFRARED DETECTORS, SURFACE ACTIVE SUBSTANCES, DOPING, WAVE FUNCTIONS, LUMINESCENCE, STARK EFFECT, N BODY PROBLEM.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Electrooptical and Optoelectronic Devices
      Optics
      Quantum Theory and Relativity

Distribution Statement : APPROVED FOR PUBLIC RELEASE