FinFET performance with Si:P and Ge:Group-III-Metal metastable contact trench alloys

Abstract

We achieved mid-10-10 Ω-cm2 n-type S/D contact resistivity (npc) and 1.9×10-9 Ω-cm2 p-type S/D contact resistivity (ppc) by employing laser-induced liquid or solid phase epitaxy (LPE/SPE) of Si:P and Ge:Group-III-Metal metastable alloys inside nano-scale contact trenches. The Ge: Group-III-Metal alloy allows for a metal-Ge Fermi level pinning effect to lower Schottky barrier height (SBH) while reducing both bulk and unipolar heterojunction resistances. Correspondingly, large Ron reduction and Id gain have been realized in scaled n- and p-FinFETs with the contact length of less than 20nm.