The use of TCAD as a powerful tool for improving device performance and process manufacturability is describe din this paper. The ability for TCAD simulation to provide quick insight and understanding to better pMOS heavy doped drain extension design is illustrated. The impact of surface dielectric property and interface condition on the HDD diffusion profile, the transistor performance, and the transistor parametric variation is discussed through the use of SIMS profiles, simulation results, and silicon dat. Significant changes in HDD profile, transistor characteristics and parametric variability are attributed to surface oriented dopant diffusion. The severity of such changes can vary with varying surface dielectric properties. Through TCAD simulations, we postulate that the surface oriented dopant diffusion is mainly due to the existence of a super steep interstitial gradient (SSIG), in addition to SPE dopant transport effects. Monte Carlo implant simulations using UT-Marlowe and SIMS profiles how that higher-energy-lower-dose HDD implant would produce a better HDD diffusion profile of same junction depth than lower- energy-higher-dose HDD implant does, as a result of SSIG. SIMS experiments designed to reduce surface oriented diffusion by using Ge and F co-implant are discussed. The SIMS profiles show that Ge is able to reduce surface oriented dopant diffusion by steric effects, but F co- implant produces the best HDD profile.
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