Impact of deep levels on the electrical conductivity and luminescence of gallium nitride codoped with carbon and silicon

Journal Article · Thu Sep 01 04:00:00 EDT 2005 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2005379· OSTI ID:20714086

Armstrong, A; Arehart, A R; Green, D; Mishra, U K; Speck, J S; Ringel, S A ^[1]

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1. Department of Electrical and Computer Engineering, Ohio State University, Columbus, Ohio 43210 (United States)

The impact of C incorporation on the deep level spectrum of n-type and semi-insulating GaN:C:Si films grown by rf plasma-assisted molecular-beam epitaxy (MBE) was investigated by the combination of deep level transient spectroscopy, steady-state photocapacitance, and transient deep level optical spectroscopy. The deep level spectra of the GaN:C:Si samples exhibited several band-gap states. A monotonic relation between systematic doping with C and quantitative trap concentration revealed C-related deep levels. A deep acceptor at E{sub c}-2.05 eV and a deep donor at E{sub c}-0.11 eV are newly reported states, and the latter is the first directly observed deep level attributed to the C{sub Ga} defect. A configuration-coordinate model involving localized lattice distortion revealed strong evidence that C-related deep levels at E{sub c}-3.0 eV and E{sub {nu}}+0.9 eV are likely identical and associated with the yellow luminescence in C-doped GaN films. Of the deep levels whose trap concentration increase with C doping, the band-gap states at E{sub c}-3.0 and 3.28 eV had the largest concentration, implying that free-carrier compensation by these deep levels is responsible for the semi-insulating behavior of GaN:C:Si films grown by MBE. The differing manner by which C incorporation in GaN may impact electrical conductivity in films grown by MBE and metal-organic chemical-vapor deposition is discussed.

• OSTI ID: 20714086
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 5 Vol. 98; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CAPACITANCE
CARBON
CHEMICAL VAPOR DEPOSITION
COORDINATES
CRYSTAL DEFECTS
CRYSTAL GROWTH
DEEP LEVEL TRANSIENT SPECTROSCOPY
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
ENERGY GAP
GALLIUM NITRIDES
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
PLASMA
SEMICONDUCTOR MATERIALS
SILICON
STEADY-STATE CONDITIONS
THIN FILMS