Deep levels in n-type AlGaN grown by hydride vapor-phase epitaxy on sapphire characterized by deep-level transient spectroscopy

2005 ◽  
Vol 87 (22) ◽  
pp. 222112 ◽  
Author(s):  
J. Osaka ◽  
Y. Ohno ◽  
S. Kishimoto ◽  
K. Maezawa ◽  
T. Mizutani
Keyword(s):  
Vapor Phase ◽  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Vapor Phase Epitaxy ◽  
Deep Levels ◽  
Hydride Vapor Phase Epitaxy ◽  
Transient Spectroscopy

Observation of Midgap States in GaN with Optical-Isothermal Capacitance Transient Spectroscopy

1996 ◽  
Vol 449 ◽  
Author(s):  
P. Hacke ◽  
H. Miyoshi ◽  
K. Hiramatsu ◽  
H. Okumura ◽  
S. Yoshida ◽  
...  
Keyword(s):  
Vapor Phase ◽  
Thermal Emission ◽  
Vapor Phase Epitaxy ◽  
Deep Levels ◽  
Hydride Vapor Phase Epitaxy ◽  
Measured Concentration ◽  
Transient Spectroscopy ◽  
Capacitance Transient ◽  
Sequential Appearance ◽  
Isothermal Capacitance Transient Spectroscopy

ABSTRACTOptical-isothermal capacitance transient spectroscopy (O-ICTS) was used to distinguish the deep levels which occur in unintentionally doped n-type GaN by means of their characteristic optical cross section. GaN grown by metalorganic vapor phase epitaxy (MOVPE) and hydride vapor phase epitaxy (HVPE) were compared. Correspondence between optical and thermal emission characteristics of previously discovered levels, E2 (∼Ec-0.55 eV) and E4 (∼EC-1.0 eV), were clearly determined by observing their sequential appearance in the ICTS spectra. Whether by thermal or optical stimulation, the emission from E4 was found to be broad in nature; it is consequently believed to involve a defect. The total measured concentration of deep levels, including a prominent level which photoionizes in the range 2.5 to 3.0 eV below the conduction band, is greater in the GaN grown by MOVPE than by HVPE that was tested.

Electron Irradiation Induced Trap In N-Type Gan

1997 ◽  
Vol 482 ◽  
Author(s):  
Z-Q. Fang ◽  
J. W. Hemsky ◽  
D. C. Look ◽  
M. P. Mack ◽  
R. J. Molnar ◽  
...  
Keyword(s):  
Electron Irradiation ◽  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Chemical Vapor ◽  
Hydride Vapor Phase Epitaxy ◽  
Organic Chemical ◽  
Electric Field Effects ◽  
Metal Organic ◽  
Transient Spectroscopy ◽  
Organic Chemical Vapor Deposition

AbstractA 1-MeV-electron-irradiation (EI) induced trap at Ec-0.18 eV is found in n-type GaN by deep level transient spectroscopy (DLTS) measurements on Schottky barrier diodes, fabricated on both metal-organic-chemical-vapor-deposition and hydride-vapor-phase-epitaxy material grown on sapphire. The 300-K carrier concentrations of the two materials are 2.3 × 1016 cm−3 and 1.3 × 1017 cm−3, respectively. Up to an irradiation dose of 1 × 1015 cm−2, the electron concentrations and pre-existing traps in the GaN layers are not significantly affected, while the EI-induced trap is produced at a rate of at least 0.2 cm−1. The DLTS peaks in the two materials are shifted slightly, possibly due to electric-field effects. Comparison with theory suggests that the defect is most likely associated with the N vacancy or Ga interstitial.

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