BCl3-containing plasmas are used to etch HtO(2), a high dielectric constant ("high-k") material. We have investigated several plasmas for their effectiveness in cleaning boron from the underlying Si Surface after BCl3 plasma etching of HfO2, while removing a minimum amount of Si. X-ray photoelectron spectroscopy with vacuum sample transfer was used for surface analysis. B cleaning was optimum in dilute H-2 plasmas (ill Ar) compared to pure H-2 plasmas. Dilute H-2 plasmas slowed B cleaning process to a controllable time. In a 1% H-2-Ar plasma, 20 s was required to clean similar to 90% B from the surface after a 60 s overetch of HfO2 in BCl3 plasmas. The Si substrate was etched < 3 mu during this cleaning period, which was considerably suppressed comparing pure H-2 plasma cleaning. Dilute I-2 plasmas (in Ar) can also clean B from the Si surfaces in a short time (10 s) but more Si Substrate was etched compared to H-2-Ar plasmas. BCl3-H-2 plasmas deposited a thick B-containing layer oil the Si Surface instead of combining etching and cleaning into one step. (c) 2006 American Vacuum Society.