Oxidation and annealing of GaAs (100) studied by photoreflectance
- Laser and Atomic Physics Division, Sandia National Laboratories, Albuquerque, New Mexico 87185 (US)
Photoreflectance (PR) has until now been a technique used primarily for characterization of bulk electronic band structure in semiconductors. However, since reflectance is an interfacial phenomenon, PR should in principle be sensitive to surface treatment as well. The present work appears to be the first quantitative use of PR to measure the effects of surface treatment. In particular, PR spectra of air-oxidized and of annealed GaAs(100) are shown to be substantially different from those of the clean surface. Spectra at the {ital E}{sub 0} (1.4 eV) and {ital E}{sub 1} (3.0 eV) transitions respond quite differently to these treatments, and the differences are explained in terms of an optical interference phenomenon due to excitons that occurs only at {ital E}{sub 0}. Effects of slow surface states have been observed with PR for the first time. The effective barrier between these states and the bulk decreases from 21{plus minus}2 to 16{plus minus} 2 meV upon air oxidation of the clean surface.
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 5369742
- Journal Information:
- Journal of Applied Physics; (USA), Journal Name: Journal of Applied Physics; (USA) Vol. 66:10; ISSN 0021-8979; ISSN JAPIA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Temperature-dependent optical band gap of the metastable zinc-blende structure [beta]-GaN
Photoreflectance Spectroscopy Study of LT-GaAs Layers Grown on Si and GaAs Substrates
Related Subjects
360603* -- Materials-- Properties
ANNEALING
ARSENIC COMPOUNDS
ARSENIDES
CHEMICAL REACTIONS
ELECTROMAGNETIC RADIATION
ENERGY GAP
EXCITONS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
HEAT TREATMENTS
HIGH TEMPERATURE
INTERFERENCE
LASER RADIATION
LOW TEMPERATURE
MEDIUM TEMPERATURE
MODULATION
OPTICAL PROPERTIES
OXIDATION
PHYSICAL PROPERTIES
PNICTIDES
PULSES
QUASI PARTICLES
RADIATIONS
SURFACES