Observation of Fe-related defects in neutron irradiated semi-insulating InP

Journal Article · Fri Jun 15 04:00:00 EDT 2001 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1343891· OSTI ID:40204179

Mari, B; Hernandez-Fenollosa, M A; Navarro, F J

Optical absorption and positron lifetime measurements have been performed on Fe-doped semi-insulating InP single crystals irradiated with thermal neutrons in a wide dose range from 0.1 to 2.7{times}10{sup 17}ncm{sup {minus}2}. Two lifetimes were found: {tau}{sub 1}=210ps is constant in all the irradiation range; and {tau}{sub 2}=340ps reaches an intensity of almost 40% at the higher fluence used. When comparing these results with those obtained on unintentionally doped InP, a large increase of the longest lifetime is observed, from 300 ps in the nondoped InP to 340 ps in the semi-insulating InP. The increase of the second lifetime in InP:Fe means that the positron traps are less attractive to positrons. These positron traps have been associated to a complex defect generated by the main neutron-originated defect, the indium vacancy, and the clusters or interstitial atoms of Fe. The optical absorption spectra show a background absorption related to Fe precipitates in as-grown InP:Fe. This background absorption disappears after neutron irradiation, suggesting the destruction of Fe precipitates by the energetic particles generated in the transmutation process of {sup 115}In. {copyright} 2001 American Institute of Physics.

• Sponsoring Organization: (US)
• OSTI ID: 40204179
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 12 Vol. 89; ISSN 0021-8979
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ABSORPTION SPECTRA
DEFECTS
MONOCRYSTALS
NEUTRONS
POSITRONS
THERMAL NEUTRONS