Published online by Cambridge University Press: 10 February 2011
Lowering process temperatures for polysilicon thin-film-transistors (TFTs) has given rise to new worries about the quality of TFT gate oxides. Specifically, presence of large amounts of SiOH bonds in gate oxides has become a matter of concern. We discuss methods for suppressing the formation of Si-OH bonds during chemical vapor deposition (CVD) of low-temperature processed (LTP) gate oxides. The use of remote-plasma CVD and control of the reaction between the silicon source gas and the oxygen source gas are both shown to be effective. We also show that decreased amounts of Si-OH bonds in LTP-CVD gate oxides result in desirable decreases in fixed oxide charge densities.