학술논문

Manufacturable Processes for $\leq$ 32-nm-node CMOS Enhancement by Synchronous Optimization of Strain-Engineered Channel and External Parasitic Resistances
Document Type
Periodical
Source
IEEE Transactions on Electron Devices IEEE Trans. Electron Devices Electron Devices, IEEE Transactions on. 55(5):1259-1264 May, 2008
Subject
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Cu contacts
external resistance
laser anneal
silicide
strain engineering
Language
ISSN
0018-9383
1557-9646
Abstract
Manufacturable processes to reduce both channel and external resistances $(R_{\rm Ext})$ in CMOS devices are described. Simulations show that $R_{\rm Ext}$ will become equivalent to strained Si channel resistance near the 32-nm logic node. Tensile stress in plasma-enhanced chemical-vapor-deposited $\hbox{SiN}_{x}$ liners is increased with UV curing, boosting the NMOS drive current by 20% relative to a neutral reference. W contact-plug resistance $(R_{c})$ is reduced by 40% by optimizing preclean, liner/barrier, and nucleation steps. Replacing the fill material with Cu reduces $R_{c}$ by $>\hbox{35}\%$ as compared to W. The Schottky barrier height of silicide contacts to p-Si is reduced by 0.12 eV with a 10% addition of Pt, resulting in a $\sim$10% increase in the PMOS drive current. By implementing a two-step anneal process $(\hbox{spike} + \hbox{laser})$, the source/drain-extension resistance can be reduced by 20%.