On the Current Flow Mechanism in Au-TiBx-n-GaN-i-Al2O3 Schottky Barrier Diodes

We investigated a current flow mechanism in the Au-TiB
_x
-
n
-GaN-
I
-AI
₂
O
₃
Schottky barrier diodes, in which space-charge region width is much over the de Broglie wavelength in GaN. An analysis of the temperature dependences of
I-V
curves of forward-biased Schottky barriers showed that, in the 80-380 K temperature range, current flow occurs as tunneling along dislocations crossing the space-charge region. The dislocation density p estimated from
I-V
curves (in accordance with the model of tunneling along the dislocation line) was ≈ 1.7=D7;10
^-7
cm
^-2
.