open access

https://hdl.handle.net/2115/90993

Interface state density distribution near conduction band edge at Al2O3/Mg-ion-implanted GaN interface formed after activation annealing using AlN cap layer

英語

2022-12-21

AIP Publishing

AIP Advances

12

125224

An interface state density (D-it) distribution near the conduction band edge (E-C) at the Al2O3/Mg-ion-implanted GaN interface was measured after ion implantation, annealing with an AlN protective cap, and cap layer removal. Mg ions were implanted into n-GaN with a Si concentration of 6 x 10(17) cm(-)(3) at a maximum Mg concentration of 2 x 10(17) cm(-)(3), resulting in the maintenance of the n-type conduction in GaN even after the activation of Mg dopants. Activation annealing was carried out at 1250 ? for 1 min using an AlN cap layer. The complete removal of the AlN cap layer was accomplished by wet etching, which was confirmed by x-ray photoelectron spectroscopy. The photoluminescence spectrum showed donor-acceptor-pair emission after annealing, indicating the activation of Mg acceptors. By applying the capacitance-voltage method to a completed metal-oxide-semiconductor diode, we derived a continuous distribution of relatively low D-it below 5 x 10(12) cm(-)(2) eV(-1), which increased monotonically toward E-C in the range from E-C - 0.15 to E-C - 0.45 eV. Compared with the D-it distribution of the as-implanted sample, the density of the discrete level at E-C - 0.25 eV generated by divacancies markedly decreased upon 1250 ? annealing.

学術雑誌論文

Accepted Manuscript

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in AIP Advances and may be found at https://aip.scitation.org/doi/full/10.1063/5.0117321.

2158-3226