Abstract
Optical deep level spectroscopy (ODLTS) and microcathodoluminescence (MCL) spectra were measured for a large group of n-GaN samples grown via metalorganic chemical vapor deposition (MOCVD), epitaxial lateral overgrowth (ELOG), or hydride vapor phase epitaxy (HVPE). In the MOCVD and ELOG samples, the ionization energy of dominant hole traps H1 was dependent on the excitation conditions and was ∼0.9 eV for high injection levels providing saturation of the ODLTS peak magnitude. The trap concentration increased with increasing Si donor concentration and correlated with the yellow band intensity in the MCL spectra. For the HVPE samples, the hole trap spectra were radically different from the MOCVD case: four hole traps-H2, H3, H4, and H5-with activation energies of 0.55, 0.65, 0.85, and 1.2 eV, respectively, were detected. In the MCL spectra, a broad green band that peaked near 2.5 eV was observed in addition to the usual yellow luminescence near 2.3 eV. This green band was attributed to the transitions involving the H4 hole traps. Possible identities of the hole traps detected in the MOCVD/ELOG and HVPE samples are discussed.
| Original language | English |
|---|---|
| Article number | 123701 |
| Journal | Journal of Applied Physics |
| Volume | 109 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 2011 Jun 15 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Physics and Astronomy(all)
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Comparison of hole traps in n-GaN grown by hydride vapor phase epitaxy, metal organic chemical vapor deposition, and epitaxial lateral overgrowth. / Polyakov, A. Y.; Lee, In-Hwan; Smirnov, N. B.; Govorkov, A. V.; Kozhukhova, E. A.; Pearton, S. J.
In: Journal of Applied Physics, Vol. 109, No. 12, 123701, 15.06.2011.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Comparison of hole traps in n-GaN grown by hydride vapor phase epitaxy, metal organic chemical vapor deposition, and epitaxial lateral overgrowth
AU - Polyakov, A. Y.
AU - Lee, In-Hwan
AU - Smirnov, N. B.
AU - Govorkov, A. V.
AU - Kozhukhova, E. A.
AU - Pearton, S. J.
PY - 2011/6/15
Y1 - 2011/6/15
N2 - Optical deep level spectroscopy (ODLTS) and microcathodoluminescence (MCL) spectra were measured for a large group of n-GaN samples grown via metalorganic chemical vapor deposition (MOCVD), epitaxial lateral overgrowth (ELOG), or hydride vapor phase epitaxy (HVPE). In the MOCVD and ELOG samples, the ionization energy of dominant hole traps H1 was dependent on the excitation conditions and was ∼0.9 eV for high injection levels providing saturation of the ODLTS peak magnitude. The trap concentration increased with increasing Si donor concentration and correlated with the yellow band intensity in the MCL spectra. For the HVPE samples, the hole trap spectra were radically different from the MOCVD case: four hole traps-H2, H3, H4, and H5-with activation energies of 0.55, 0.65, 0.85, and 1.2 eV, respectively, were detected. In the MCL spectra, a broad green band that peaked near 2.5 eV was observed in addition to the usual yellow luminescence near 2.3 eV. This green band was attributed to the transitions involving the H4 hole traps. Possible identities of the hole traps detected in the MOCVD/ELOG and HVPE samples are discussed.
AB - Optical deep level spectroscopy (ODLTS) and microcathodoluminescence (MCL) spectra were measured for a large group of n-GaN samples grown via metalorganic chemical vapor deposition (MOCVD), epitaxial lateral overgrowth (ELOG), or hydride vapor phase epitaxy (HVPE). In the MOCVD and ELOG samples, the ionization energy of dominant hole traps H1 was dependent on the excitation conditions and was ∼0.9 eV for high injection levels providing saturation of the ODLTS peak magnitude. The trap concentration increased with increasing Si donor concentration and correlated with the yellow band intensity in the MCL spectra. For the HVPE samples, the hole trap spectra were radically different from the MOCVD case: four hole traps-H2, H3, H4, and H5-with activation energies of 0.55, 0.65, 0.85, and 1.2 eV, respectively, were detected. In the MCL spectra, a broad green band that peaked near 2.5 eV was observed in addition to the usual yellow luminescence near 2.3 eV. This green band was attributed to the transitions involving the H4 hole traps. Possible identities of the hole traps detected in the MOCVD/ELOG and HVPE samples are discussed.
UR - http://www.scopus.com/inward/record.url?scp=79960193469&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79960193469&partnerID=8YFLogxK
U2 - 10.1063/1.3599894
DO - 10.1063/1.3599894
M3 - Article
AN - SCOPUS:79960193469
VL - 109
JO - Journal of Applied Physics
JF - Journal of Applied Physics
SN - 0021-8979
IS - 12
M1 - 123701
ER -