60 nm gate length Al2O3 / In0.53Ga0.47As gate-first MOSFETs using InAs raised source-drain regrowth

Given adequately low source/drain (S/D) access resistivity and dielectric interface trap density (R
access
< 50 Ω-µ,
¹
and D
it
< 2 · 10
¹²
cm
⁻²
eV
^−1,2
respectively), InGaAs MOSFETs will provide greater on-state current than silicon MOSFETs at the same effective oxide thickness (EOT). The access resistance must be obtained in a self-aligned structure with a contacted gate pitch ∼4 times the physical gate length (L
g
), e.g. 116 nm at 32 nm L
g
,
³
while control of short channel effects demands that the S/D region depth be only a fraction of gate length; low-resistance, ultra-shallow fully self-aligned III-V MOS processes must therefore be developed. Here we report a 60 nm L
g
In
0.53
Ga
0.47
As MOSFET fabricated in a gate-first process with self-aligned raised InAs S/D access regions formed by MBE regrowth. The devices have a peak drive current of 1.36 mA/µm at V
ds
= 1.25 V and V
gs
= 3 V and an R
on
= 341 ohm-µm. To our knowledge this is the lowest R
on
and smallest L
g
reported to date for In
0.53
Ga
0.47
As surface channel MOSFETs.
⁴