Fabrication of Self-Aligned Enhancement-Mode $ \hbox{In}_{0.53}\hbox{Ga}_{0.47}\hbox{As}$ MOSFETs With $ \hbox{TaN/HfO}_{2}\hbox{/AlN}$ Gate Stack

In this letter, we report the fabrication and characterization of self-aligned inversion-type enhancement-mode In
_0.53
Ga
_0.47
As metal-oxide-semiconductor field-effect transistors (MOSFETs). The In
_0.53
Ga
_0.47
As surface was passivated by atomic layer deposition of a 2.5-nm-thick AIN interfacial layer. In
_0.53
Ga
_0.47
As MOS capacitors showed an excellent frequency dispersion behavior. A maximum drive current of 18.5 muA/mum was obtained at a gate overdrive of 2 V for a MOSFET device with a gate length of 20 mum. An I
_on
/
_off
ratio of 104, a positive threshold voltage of 0.15 V, and a subthreshold slope of ~165 mV/dec were extracted from the transfer characteristics. The interface-trap density is estimated to be ~7-8 times 10
¹²
cm
^-2
ldr eV
^-1
from the subthreshold characteristics of the MOSFET.