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Diffusion Effect between Schottky Metals and AlGaN/GaN Heterostructure during High Temperature Annealing Process

Published online by Cambridge University Press:  31 January 2011

Young-Hwan Choi
Affiliation:
wink7@emlab.snu.ac.kr, Seoul National University, Seoul, Korea, Republic of
Jiyong Lim
Affiliation:
jamdol2@snu.ac.kr, Seoul National University, Seoul, Korea, Republic of
Young-Shil Kim
Affiliation:
yskim@emlab.ac.kr, Seoul National University, Seoul, Korea, Republic of
Min-Koo Han
Affiliation:
mkh@snu.ac.kr, Seoul National University, Seoul, Korea, Republic of
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Abstract

We have investigated the change of the Schottky contact surface and the interface between Schottky metals and AlGaN/GaN heterostructure after the annealing process for 35 min at 300 °C. The secondary ion mass spectroscopy (SIMS) and the scanning electron microscopy (SEM) show that the Schottky metals and AlGaN/GaN heterostructure interacted actively during the annealing process. The atoms in Schottky contact and AlGaN/GaN heterostructure diffused interactively and the surface roughness of Schottky contact was increased. After the annealing process for fabricated AlGaN/GaN High-Electron-Mobility Transistor (HEMT), the threshold voltage was shifted by +0.2 V and the leakage current was decreased by 40 %.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

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