Body Thickness Dependence of Impact Ionization in a Multiple-Gate FinFET

Abstract

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The body thickness dependence of impact ionization for a multiple-gate fin field-effect transistor (FinFET) is presented. It is found that the nonlocal effect and series resistance are distinct features of reduced impact ionization in the multiple-gate FinFET, and these effects become more pronounced as the body thickness decreases. The impact ionization constant <formula formulatype="inline"><tex>$B_{i}$</tex></formula> is newly extracted by considering the series resistance and nonlocal carrier heating effect. A refined analytical substrate current model is developed from the previous model and revamped for multiple-gate devices. The new substrate current model is then compared with measurement data, and good agreement is observed. </para>