Photocurrent decay in {ital n}-type GaN thin films

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.117392· OSTI ID:286897

Qiu, C H ^[1]; Melton, W ^[2]; Leksono, M W; Pankove, J I ^[3]; Keller, B P; DenBaars, S P ^[4]

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1. Astralux Inc., 2500 Central Avenue, Boulder, Colorado 80301 (United States)
2. Department of Electrical Engineering, University of Colorado, Boulder, Colorado 80309-0425 (United States)
3. Astralux, Inc., 2500 Central Avenue, Boulder, Colorado 80301 (United States)
4. Electrical and Computer Engineering and Materials Departments, University of California, Santa Barbara, California 93106 (United States)

Minority carrier relaxation in undoped {ital n}-type gallium nitride (GaN) thin films was studied by photoconductivity decay measurements in the time span from 50 ns to 50 s. The decay is characterized by an initial exponential decay followed by a quasi-power-law decay for decades of time longer than 1 {mu}s. The decay rate is insensitive to the electron concentration and is only slightly temperature dependent. The results are discussed in terms of hole trapping at gap states and subsequent recombination. The studies revealed that the dominant recombination mechanism is very different from recombination through dislocations and that the valence band-tail states in {ital n}-type GaN seem to be negatively charged. {copyright} {ital 1996 American Institute of Physics.}

• DOE Contract Number: FG03-95ER86024
• OSTI ID: 286897
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 9 Vol. 69; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DECAY
DISLOCATIONS
GALLIUM NITRIDES
MINORITY CARRIERS
PHOTOCONDUCTIVITY
RECOMBINATION
TEMPERATURE DEPENDENCE
THIN FILMS
TRAPPING