Characteristics of SiF4 Plasma Doping (PLAD)

SiF
₄
PLAD has been systematically characterized and optimized. The correlations between the etching, deposition, retained F dose and profile as functions of the PLAD process variables including implant voltage, RF power, pressure, pulse duty cycle, and the diluting gases have been extensively investigated. It was found that PLAD process by using pure SiF
₄
is in an etching or RIE regime, but can be adjusted to minimize the etching effect. It was found that diluting SiF
₄
with different gases can significantly impact etching and deposition characteristics. The selectivity of etching and deposition behaviors on the different substrate materials such as poly-Si, silicon oxide, and silicon nitride have been explored. With the understanding of these behaviors, SiF
₄
PLAD can be optimized for multiple precision doping and material modification applications.