Shallow radiation defect levels in neutron-irradiated extrinsic p-type silicon

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1980

OSTI ID:5594154

Young, M H.W.

Neutron transmutation doping of silicon with phosphorus makes use of a (n,..gamma..) nuclear reaction in which Si/sup 30/ captures a thermal neutron and transmutes to P/sup 31/. In this investigation very unusual radiation defects in neutron-irradiated, extrinsic p-type silicon which is counterdoped by phosphorus produced by neutron transmutation are discovered, and their nature and properties studied. The electrical properties of the radiation defects and impurity levels are studied. The electrical properties of the radiation defects and impurity levels are studied by performing Hall effect and resistivity measurements as a function of temperature. Optical properties of the irradiated silicon are investigated using measurements of low-temperature relative photoconductive spectral response as a function of wavelength of incident infrared radiation. In partially annealed, neutron-irradiated, low-oxygen Si:Ga, a very distinctive and unusual acceptor defect center is observed. The electronic energy level associated with this center, denoted A1, is found in this work to be located at E/sub v/ + 0.025 +- 0.003 eV in the forbidden gap of silicon. An A1 defect with slightly deeper electronic energy level (approx. E/sub v/ + 0.03 eV) is seen in irradiated, low-oxygen Si:In, and a similar shallow level is seen in irradiated, low-oxygen Si:Al as well. It is therefore concluded that the defect complex responsible for the A1 level contains a Column III atom. Optical studies show the peak optical absorption cross section (sigma/sub A/) of the A1 center is approximately 2.4 x 10/sup -14/ cm/sup 2/, which is larger than sigma/sub A/ for any other known impurity defect in silicon.

• Research Organization: California Univ., Los Angeles (USA)
• OSTI ID: 5594154
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360605* -- Materials-- Radiation Effects
BARYON REACTIONS
BARYONS
CRYSTAL DEFECTS
CRYSTAL DOPING
CRYSTAL STRUCTURE
DOPED MATERIALS
ELECTRICAL PROPERTIES
ELEMENTARY PARTICLES
ELEMENTS
FERMIONS
HADRON REACTIONS
HADRONS
MATERIALS
NEUTRON REACTIONS
NEUTRONS
NUCLEAR REACTIONS
NUCLEON REACTIONS
NUCLEONS
OPTICAL PROPERTIES
P-TYPE CONDUCTORS
PHYSICAL PROPERTIES
SEMICONDUCTOR MATERIALS
SEMIMETALS
SILICON
THERMAL NEUTRONS
TRANSMUTATION