Rapid thermal chemical vapor deposited sidewall spacer dielectrics for deep submicron MOSFET technology.

摘要

A low pressure rapid thermal chemical vapor deposition (RTCVD) process has been investigated as an alternative to conventional furnace low pressure chemical vapor deposition (LPCVD) process for formation of sidewall spacer dielectric to be used in advanced metal-oxide-semiconductor-field-effect-transistor (MOSFET) technology. RTCVD oxide, oxynitride and nitride films were formed using silane (SiH;Refractive index and wet etch rate measurements suggest that the as-deposited RTCVD oxides are better in material quality than conventional furnace LPCVD sidewall spacer oxides and with a short 900;Process and device simulators were used extensively to study and design advanced lightly doped drain (LDD) structures with different RTCVD spacer dielectrics and evaluate their effect on improving the device performance and reliability. PISCES-IIB simulations demonstrated that by adjusting the LDD doping concentration in the device we could shift the location of the peak lateral electric field in the device near the gate edge or slightly under the sidewall spacer resulting in less hot carrier injection into the gate dielectric and more into the sidewall spacer, thus allowing us to qualitatively separate hot carrier degradation induced by the gate dielectric and the sidewall spacer. LDD arsenic junction profiles were simulated and compared to arsenic SIMS profiles to calibrate the process simulators and carefully match the LDD junction profiles used in the PISCES-IIB simulations.;I