Enhancement mode n-MOSFET with high-κ dielectric on GaAs substrate

In this paper, we report MOS heterostructures grown by molecular beam epitaxy on III-V substrates, employing a high-κ dielectric stack comprised of gallium oxide and gadolinium gallium oxide. Mobilities exceeding 12,000 and 6,000 cm
²
/Vs, for sheet carrier concentration n
_s
of about 2.5x10
¹²
cm
^-2
were measured on MOSFET structures on InP and GaAs substrates, respectively. These structures were designed for enhancement mode operation and include a 10 nm thick strained InGa
_1-x
As channel layer with In mole fraction x of 0.3 and 0.75 on GaAs and InP substrates, respectively.