Contact-Resistance Reduction for Strained n-FinFETs With Silicon–Carbon Source/Drain and Platinum-Based Silicide Contacts Featuring Tellurium Implantation and Segregation

摘要

Tellurium (Te) implantation was introduced to tune the effective electron Schottky barrier height (SBH) $Phi_{B}^{n}$ of platinum-based silicide (PtSi) contacts formed on n-type silicon–carbon (Si:C). Te introduced by ion implantation prior to Pt deposition segregated at the PtSi:C/Si:C interface during PtSi:C formation. The presence of Te at the PtSi:C/Si:C interface leads to a low $Phi_{B}^{n}$ of 120 meV for PtSi:C contacts. The integration of Te-segregated PtSi:C contacts on strained n-channel fin field-effect transistors (FinFETs) with Si:C source/drain (S/D) stressors achieves the lowering of the parasitic series resistance $R_{SD}$ by $sim$62% and increases the saturation drive current by $sim$22%. The Te-segregated contact-resistance reduction technology does not degrade the short-channel effects and positive-bias temperature instability characteristics of n-FinFETs with Si:C S/D. As PtSi has a low SBH for holes and is a suitable contact for p-FinFETs, this new contact-resistance reduction technology has potential to be introduced as a single-metal-silicide dual-barrier-height solution for future complementary metal–oxide–semiconductor FinFET technology.