Accession Number : ADA267178


Title :   Optoelectronics based on SiGe/Si Heterostructures


Descriptive Note : Annual rept. 15 Oct 91-14 Oct 92,


Corporate Author : CALIFORNIA UNIV LOS ANGELES DEPT OF ELECTRICAL ENGINEERING


Personal Author(s) : Wang, Kang L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a267178.pdf


Report Date : 14 Jan 1993


Pagination or Media Count : 18


Abstract : The overall objective of the research is to explore SiGe/Si heterostructures for optoelectronic applications. In addition to exploration of new devices, alternative growth techniques for achieving layer thickness to monolayer scale and doping control are also investigated. We have discovered a new transition at normal incidence for p-type quantum well structures, in addition to previously observed intersubband transition. One of the advantages of this intervalence band transition is the detection of infrared at normal incidence. The application of these transitions for the fabrication of tunable normal incidence infrared detectors have also demonstrated. We have also demonstrated normal incidence intersubband transition in the conduction band of SiGe/Si quantum wells grown on (110) Si substrate due to the nonvanishing off- diagonal elements of the effective mass tensor. 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 wave functions into the spacer where the impurity scattering is minimal. In the area of the growth control of SiGe epitaxial layers, we have modified a MBE system for handling the gaseous species for gas beam epitaxy study.


Descriptors :   *QUANTUM WELLS , *SILICON , *GERMANIUM , ELECTRONICS , OPTICS , THICKNESS , SCATTERING , FABRICATION , SUBSTRATES , MOLECULAR BEAMS , TRANSPORT PROPERTIES , DOPING , CONDUCTION BANDS , TRANSITIONS , RELAXATION , MOLECULAR STRUCTURE , INFRARED DETECTORS , TRANSPORT , VALENCE BANDS , PENETRATION , SPACERS , LUMINESCENCE , WAVE FUNCTIONS , ABSORPTION , TENSORS , GASES , IMPURITIES , EPITAXIAL GROWTH , MOBILITY , DETECTORS , LAYERS , MASS


Subject Categories : Electrooptical and Optoelectronic Devices
      Electricity and Magnetism
      Optics
      Quantum Theory and Relativity


Distribution Statement : APPROVED FOR PUBLIC RELEASE