Title :
The investigation of custom grown vertical zone melt semi-insulating bulk gallium arsenide as a radiation spectrometer
Author :
McGregor, D.S. ; Antolak, A.J. ; Chui, H.C. ; Cross, E.S. ; Fang, Z.-Q. ; Goorsky, M.S. ; Henry, R.L. ; Look, D.C. ; Mier, M.G. ; Morse, D.H. ; Nordquist, P.E.R. ; Olsen, R.W. ; Pocha, M. ; Schieber, M. ; Schlesinger, T.E. ; Soria, E. ; Toney, J.E. ; Yoon
Author_Institution :
Sandia Nat. Labs., Livermore, CA, USA
Abstract :
Vertical zone melt (VZM) bulk GaAs ingots have been zone refined (ZR) and zone leveled (ZL) to reduce EL2 deep donor levels and impurity concentrations with the intent of improving properties for gamma ray detectors. ZR and ZL GaAs ingots had background impurity levels and deep donor EL2 concentrations near or below detectable limits. The crystallinity of the material was slightly superior to commercial liquid encapsulated Czochralski (LEC) material, and nearly equivalent to commercial vertical gradient freeze (VGF) material. However, the homogeneity of the electrical properties for the ZL and ZR VZM material was inferior to commercially available material. Resulting gamma ray spectra was poor from detectors fabricated with the ZL or ZR VZM material
Keywords :
III-V semiconductors; crystal growth from melt; deep levels; gallium arsenide; gamma-ray detection; gamma-ray spectra; gamma-ray spectrometers; impurity states; semiconductor counters; semiconductor growth; zone melting; EL2 deep donor levels; GaAs; crystallinity; gamma ray detectors; impurity concentration; semi-insulating bulk sample; vertical zone melting; zone levelling; zone refining; Crystalline materials; Crystallization; Gallium arsenide; Gamma ray detectors; Impurities; Laboratories; Refining; Spectroscopy; Voltage; Zirconium;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference Record, 1995., 1995 IEEE
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-3180-X
DOI :
10.1109/NSSMIC.1995.504182
