TY - JOUR
T1 - Optical studies of the effect of oxidation on GaN
AU - Karaoglan-Bebek, Gulten
AU - Hwan Woo, Jung
AU - Nikishin, Sergey
AU - Rusty Harris, Harlan
AU - Holtz, Mark
PY - 2014
Y1 - 2014
N2 - Optical studies are reported of GaN following oxide layer growth using thermal oxidation and atomic layer deposition (ALD). The low-temperature photoluminescence (PL) probes the topmost GaN layer (<100 nm) where any influence from the oxide is expected. Thermal oxidation results in a 6 meV blue shift of the main PL band (3.478 eV) that is attributed to stress due to formation of GaON/β-Ga2O3 upon the GaN surface. A weak PL feature at ∼3.38 eV is due to diffusion of oxygen into the GaN. The Al2O3 deposited by ALD does not result in the 3.38 eV band following deposition and subsequent annealing. In contrast, HfO2 deposited by ALD results in sub-band gap features, which strengthen upon annealing. No appreciable stress is observed for either oxide deposited using ALD, which are not expected to produce GaON/β-Ga2O3 layer.
AB - Optical studies are reported of GaN following oxide layer growth using thermal oxidation and atomic layer deposition (ALD). The low-temperature photoluminescence (PL) probes the topmost GaN layer (<100 nm) where any influence from the oxide is expected. Thermal oxidation results in a 6 meV blue shift of the main PL band (3.478 eV) that is attributed to stress due to formation of GaON/β-Ga2O3 upon the GaN surface. A weak PL feature at ∼3.38 eV is due to diffusion of oxygen into the GaN. The Al2O3 deposited by ALD does not result in the 3.38 eV band following deposition and subsequent annealing. In contrast, HfO2 deposited by ALD results in sub-band gap features, which strengthen upon annealing. No appreciable stress is observed for either oxide deposited using ALD, which are not expected to produce GaON/β-Ga2O3 layer.
UR - http://www.scopus.com/inward/record.url?scp=84893231349&partnerID=8YFLogxK
U2 - 10.1116/1.4858467
DO - 10.1116/1.4858467
M3 - Article
AN - SCOPUS:84893231349
VL - 32
JO - Journal of Vacuum Science and Technology B:Nanotechnology and Microelectronics
JF - Journal of Vacuum Science and Technology B:Nanotechnology and Microelectronics
SN - 2166-2746
IS - 1
M1 - 011213
ER -