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M. Okamoto1, K. Kakushima2, P. Ahmet1, Y. Kataoka2, A. Nishiyama2, N. Sugii2, K. Tsutsui2, K. Natori1, T. Hattori1, and H. Iwai11Frontier Research Center, Tokyo Institute of Technology
2Interdisciplinary Graduate School of Science and Technology, Tokyo Institute of [email protected]
Extraction of Energy Band Diagram of AlGaN/GaN with SiO2 Capped Annealing using X-ray Photoelectron Spectroscopy
ρc is currently 10-5 Ωcm-2.
ρc is necessary with 10-6 Ωcm-2
for lateral GaN device
Power electronics materialResistance of GaN
Conclusions
XPS measurement of AlGaN
Purpose
Al 1s with SiO2-capped annealing shifted to large band energy
N vacancy can be formed AlGaN layer SiO2-capped annealing can expect the formation by uniform contact by combining it with TiSi2 electrode
We would like to thank Prof. Nohira with Tokyo City University for XPS measurement
non annealing
annealing
0 500 600400300 700 800 900 9502001000 500 600400300 700 800 900 950200100
3.0 2.52.01.51.00.50.00 500 600400300 700 800 900 9502001000 500 600400300 700 800 900 950200100
3.0 2.52.01.51.00.50.0
TiSi2 with SiO2annealing
TiSi2 without SiO2annealing
Voltage[V]0 500 600400300 700 800 900 9502001000 500 600400300 700 800 900 950200100
3.0 2.52.01.51.00.50.00 500 600400300 700 800 900 9502001000 500 600400300 700 800 900 950200100
3.0 2.52.01.51.00.50.0
TiSi2 with SiO2annealing
TiSi2 without SiO2annealing
Voltage[V]
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0-5 -2 -1-3-4 0 1 2 3 4 5-5 -2 -1-3-4 0 1 2 3 4 5
Curre
nt[m
A]
Voltage [V]
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0-5 -2 -1-3-4 0 1 2 3 4 5-5 -2 -1-3-4 0 1 2 3 4 5
Curre
nt[m
A]
Voltage [V]
950oCTiSi2 without SiO2annealing
TiSi2 with SiO2annealing
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0-5 -2 -1-3-4 0 1 2 3 4 5-5 -2 -1-3-4 0 1 2 3 4 5
Curre
nt[m
A]
Voltage [V]
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0-5 -2 -1-3-4 0 1 2 3 4 5-5 -2 -1-3-4 0 1 2 3 4 5
Curre
nt[m
A]
Voltage [V]
950oCTiSi2 without SiO2annealing
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0-5 -2 -1-3-4 0 1 2 3 4 5-5 -2 -1-3-4 0 1 2 3 4 5
Curre
nt[m
A]
Voltage [V]
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0
2.0
0.51.01.5
0.0
-0.5
-1.0-1.5
-2.0-5 -2 -1-3-4 0 1 2 3 4 5-5 -2 -1-3-4 0 1 2 3 4 5
Curre
nt[m
A]
Voltage [V]
950oCTiSi2 without SiO2annealing
TiSi2 with SiO2annealing
Al 1s with SiO2-capped annealing shifted to large band energy
N vacancy is formed about 1.7×1017cm-3
Al1s
0.2eV
SiO2 AlGaN GaN
Band Structure of Al 1s
Tunneling currents increase
N vacancy is formed AlGaN layer
O atom from SiO2-capped is possible to be in N vacancy
TiSi2 electrode with SiO2-capped annealing is obtained decrease trend
Current‐voltage characteristics
TiN/TiSi2
Fabrication ProcessResults
Introduction
①Low metal function which reacts area metal→TiSi2 electrode(metal function 4.5eV melting point 1540oC)
② Nitrogen vacancy by SiO2T.Hasizume,J.Vac.Sci. Technol,B 21(4)(2003)
Realization of low contact resistance
Low contact resistance of approach
①Forming nitrogen vacancy ②Tunneling AlGaN layer
100 1000 1000
10
1
0.1
0.01オン抵抗
, Ron
A(m
Ωcm
2 )
Cg=35nF/cm2
Lch=0.5µmVg-Vth=5V
縦型
GaNデバイス限界
ρc=10µΩcm2
1µΩcm2
0.1µΩcm2
0.01µΩcm2
損失60%減横型
Siデバイス限界
750V 横型GaNデバイス
60% Loss
Limit o
f vert
ical G
aNde
vices
Limit of la
teral devices Lateral GaN
device
Voltage(V)
R o
n A
(mΩ
cm2 )
