Electrical Activation, Deactivation, and Reactivation Mechanism Study of Plasma Doping Processes

Advanced doping techniques in low-energy high-dose regimes including n-type PH3 and AsH3 plasma doping (PLAD) and p-type B2H6 and BF3 PLAD are studied and characterized on the electrical activation, deactivation, and reactivation mechanisms. Because deactivation and reactivation characteristics are independent of ion species and dependent only on the carrier, electrical-assisted diffusion of carriers (trap in native oxide) is confirmed as a hypothesis of a major dopant deactivation kinetics. Secondary ion mass spectrometry/angle-resolved X-ray photoelectron spectroscopy and Hall methods are used in this paper to supply more supporting evidence and data. With characteristics similar to those of beam-line (BL)-based implants, n-type PLAD shows more serious deactivation than p-type PLAD. n-type PLAD shows a more significant reactivation effect than their BL implant counterparts. According to the deactivation mechanism study, a solution was proposed and used to reduce the deactivation issue for nMOS devices.