Pressure dependence of impurity levels in semiconductors: The deep gold acceptor level and shallow donor and acceptor levels in silicon

Journal Article · Fri May 15 00:00:00 EDT 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.35.7575· OSTI ID:6615155

Samara, G A; Barnes, C E

The effects of hydrostatic pressure on the properties of the deep gold (Au) acceptor level and on the binding energies of shallow donors and acceptors in silicon are presented and discussed. The pressure dependences of the Gibbs free energy, enthalpy, and entropy associated with electron emission from the Au acceptor were determined from measurements of the electron emission rate and electron-capture cross section (sigma/sub n/) as functions of pressure and temperature. The results allow determination of the breathing-mode lattice relaxation accompanying electron emission from this center. The relaxation is found to be relatively large and inward (i.e., contraction). This appears to be the first quantitative determination of this relaxation for any electronic level in any semiconductor. Other highlights of the results on the Au acceptor are the findings that (i) the energy of this level is pinned to neither the conduction- nor valence-band edges, contrary to earlier belief and (ii) sigma/sub n/, which is known to be temperature independent, is also pressure independent. This latter result is discussed in terms of possible mechanisms for nonradiative electron capture. For the shallow donors and acceptors, the pressure derivatives of the binding energies are over an order of magnitude smaller than those of the energy gap and the Au acceptor, i.e., these levels remain essentially pinned to their corresponding band edges, as expected. These results can be understood in terms of effective-mass theory.

• Research Organization: Sandia National Laboratories, Albuquerque, New Mexico 87185
• OSTI ID: 6615155
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 35:14
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
SILICON
ELECTRONIC STRUCTURE
IMPURITIES
CAPTURE
CROSS SECTIONS
DEEP LEVEL TRANSIENT SPECTROSCOPY
EFFECTIVE MASS
ENERGY LEVELS
ENTHALPY
ENTROPY
EXPERIMENTAL DATA
FREE ENTHALPY
GOLD ADDITIONS
PRESSURE DEPENDENCE
RADIATIONLESS DECAY
ALLOYS
DATA
DE-EXCITATION
ELEMENTS
ENERGY
ENERGY TRANSFER
ENERGY-LEVEL TRANSITIONS
GOLD ALLOYS
INFORMATION
MASS
NUMERICAL DATA
PHYSICAL PROPERTIES
SEMIMETALS
SPECTROSCOPY
THERMODYNAMIC PROPERTIES
360603* - Materials- Properties