Technology options for reducing contact resistances in nanoscale metal-oxide-semiconductor field-effect transistors

Abstract

Technology options for reducing contact resistances in advanced transistors will be discussed. With scaling down of the size of metal-oxide-semiconductor field-effect transistors (MOSFETs) and with channel strain engineering to increase carrier mobility or reduce channel resistance, the external series resistance Rext has become a more significant component of the total resistance between the source and the drain regions. An important component of Rext is the contact resistance RC between contact metallization and the heavily doped source or drain (S/D) region. Solutions for reducing RC or the Schottky barrier height between the contact metal and the S/D regions will be reviewed.