Enhancement-Mode Buried-Channel $\hbox{In}_{0.7} \hbox{Ga}_{0.3}\hbox{As/In}_{0.52}\hbox{Al}_{0.48}\hbox{As}$ MOSFETs With High- $\kappa$ Gate Dielectrics

Abstract

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The operation of long- and short-channel enhancement-mode <formula formulatype="inline"> <tex>$\hbox{In}_{0.7} \hbox{Ga}_{0.3}\hbox{As}$</tex></formula>-channel MOSFETs with high-<formula formulatype="inline"><tex>$\kappa$</tex></formula> gate dielectrics are demonstrated for the first time. The devices utilize an undoped buried-channel design. For a gate length of 5 <formula formulatype="inline"> <tex>$\mu\hbox{m}$</tex></formula>, the long-channel devices have <formula formulatype="inline"><tex>$V_{t} = + \hbox{0.25}\ \hbox{V}$</tex></formula>, a subthreshold slope of 150 mV/dec, an equivalent oxide thickness of 4.4 <formula formulatype="inline"><tex>$+/-$</tex></formula> 0.3 nm, and a peak effective mobility of 1100 <formula formulatype="inline"><tex>$\hbox{cm}^{2}/\hbox{V} \cdot \hbox{s}$</tex></formula>. For a gate length of 260 nm, the short-channel devices have <formula formulatype="inline"><tex>$V_{t} = + \hbox{0.5}\ \hbox{V}$</tex> </formula> and a subthreshold slope of 200 mV/dec. Compared with Schottky-gated high-electron-mobility transistor devices, both long- and short-channel MOSFETs have two to four orders of magnitude lower gate leakage. </para>