Spatially resolved localized vibrational mode spectroscopy of carbon in liquid encapsulated Czochralski grown gallium arsenide wafers

Technical Report · Fri Apr 01 00:00:00 EST 1988

DOI:https://doi.org/10.2172/5398032· OSTI ID:5398032

Yau, Waifan

Substitutional carbon on an arsenic lattice site is the shallowest and one of the most dominant acceptors in semi-insulating Liquid Encapsulated Czochralski (LEC) GaAs. However, the role of this acceptor in determining the well known W'' shape spatial variation of neutral EL2 concentration along the diameter of a LEC wafer is not known. In this thesis, we attempt to clarify the issue of the carbon acceptor's effect on this W'' shaped variation by measuring spatial profiles of this acceptor along the radius of three different as-grown LEC GaAs wafers. With localized vibrational mode absorption spectroscopy, we find that the profile of the carbon acceptor is relatively constant along the radius of each wafer. Average values of concentration are 8 {times} 10E15 cm{sup -3}, 1.1 {times} 10E15 cm{sup -3}, and 2.2 {times} 10E15 cm{sup -3}, respectively. In addition, these carbon acceptor LVM measurements indicate that a residual donor with concentration comparable to carbon exists in these wafers and it is a good candidate for the observed neutral EL2 concentration variation. 22 refs., 39 figs.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5398032
• Report Number(s): LBL-25790; ON: DE90003121; TRN: 89-031567
• Resource Relation: Other Information: Thesis (M.S.)
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
GALLIUM ARSENIDES
CARBON ADDITIONS
SEMICONDUCTOR MATERIALS
ABSORPTION SPECTROSCOPY
BAND THEORY
CHARGE STATE
CRYOSTATS
FERMI LEVEL
INTERFEROMETERS
PHOTOCONDUCTORS
SPECTROMETERS
VIBRATIONAL STATES
ALLOYS
ARSENIC COMPOUNDS
ARSENIDES
CONTROL EQUIPMENT
ENERGY LEVELS
EQUIPMENT
EXCITED STATES
GALLIUM COMPOUNDS
MATERIALS
MEASURING INSTRUMENTS
PNICTIDES
SPECTROSCOPY
THERMOSTATS
656002* - Condensed Matter Physics- General Techniques in Condensed Matter- (1987-)
360201 - Ceramics
Cermets
& Refractories- Preparation & Fabrication