Dual beam laser annealing for contact resistance reduction and its impact on VLSI integrated circuit variability

Abstract

Introduction of a dual beam (DB) millisecond (mSec) or nanosecond (nSec laser annealing in contact module results in a drastic reduction of contact resistivity. Dependence of this benefit on laser annealing parameters is detailed. The annealing power/temperature condition needed for initiating solid or liquid phase epitaxy (SPE, LPE defines a lower process boundary, while impact of laser annealing on transistor parameters, such as Vt and gate stack, defines an upper process boundary and translates to with-in-die (WID Vt variation. Combining DB laser annealing technique with process-friendly layouts enables contact resistance benefit without degrading product level variability.