Advertisement
Published in:
01-07-2015
A comparative study of atomic layer deposition of Al2O3 and HfO2 on AlGaN/GaN
Published in: Journal of Materials Science: Materials in Electronics | Issue 7/2015
Log inActivate our intelligent search to find suitable subject content or patents.
Select sections of text to find matching patents with Artificial Intelligence. powered by
Select sections of text to find additional relevant content using AI-assisted search. powered by
Abstract
The atomic layer depositions of Al2O3 and HfO2 on AlGaN/GaN were systematically studied. The band alignments of Al2O3/AlGaN and HfO2/AlGaN were investigated using in situ X-ray photoelectron spectroscopy. A conduction band offset of 1.8 and 1.1 eV were observed for Al2O3/AlGaN and HfO2/AlGaN, respectively. The Al2O3 and HfO2 dielectric layers were found to reduce the leakage current as expected with respect to metal/AlGaN/GaN Schottky diodes, but neither changes the surface states of AlGaN. The positive ionized surface donor states density and average interface state density (D
it
) below the AlGaN conduction band edge (0.34 < E
C
− E
T
< 0.50 eV), extracted from capacitance voltage (C–V) curves, were ~5 × 1013 cm−2 and 1.1 × 1014 cm−2 eV−1, respectively.