Accession Number : ADA305644

Title :   Use of Electroreflectance to Characterize Materials with a View to Predict Device Performance.

Descriptive Note : Final rept. 1 Sep 89-31 Aug 93,

Corporate Author : ILLINOIS UNIV AT CHICAGO CIRCLE DEPT OF PHYSICS

Personal Author(s) : Garland, James W.

PDF Url : ADA305644

Report Date : 27 FEB 1996

Pagination or Media Count : 24

Abstract : The work performed under this contract was centered on the optical characterization of semiconductor heterojunctions, multiple-layered structures and heavily doped. This concentration on semiconductor structures of great importance for device applications was began in the second half of our previous contracts. Because of the shift from the measurement of optical data around the E1 and E1+A1 critical points of bulk materials or optically thick films to the measurement of data around E0 and E0+A0 on complex structures, entirely new theoretical approaches and computer programs were required for the analysis of the data. Four new approaches to the data were developed, one of which involved a new basic theory. This work enabled us to determine from electroreflectance data the detailed band profile of ZnSe/GaAs heterojunctions, including the band offset and the magnitude and range of the ZnGa inter-diffusion. Another major accomplishment was the accurate measurement of the band offset of Ga As/GahiP quantum wells and superlattices, which involved the observation and identification of 29 different optical transitions. A new experimental technique, vacuum electroreflectance, was used to study high-doped GaAs, which resulted in a new theory of photoreflectance and contactless electroreflectance. This contract resulted in 22 publications including 6 Ph.D. theses. (AN)

Descriptors :   *QUANTUM WELLS, *HETEROJUNCTIONS, COMPUTER PROGRAMS, OPTICAL PROPERTIES, QUANTUM THEORY, GALLIUM ARSENIDES, PHOTOLUMINESCENCE, SIGNAL TO NOISE RATIO, SUPERLATTICES, VOLTAGE, OPTICAL MATERIALS, ENERGY GAPS, EPITAXIAL GROWTH, ELECTRIC FIELDS, OPTICAL DATA, SEMICONDUCTORS, DIELECTRIC FILMS, BULK MATERIALS, OPTICAL ANALYSIS, ALUMINUM ARSENIDES, DIFFUSION, DOPING, REFLECTANCE, ELECTROLYTES, ENERGY BANDS, BAND SPECTRA, RAMAN SPECTRA, PHASE MODULATION, ZINC SELENIDES.

Subject Categories : Electrical and Electronic Equipment
      Quantum Theory and Relativity
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE