Ultrathin oxide gate dielectrics prepared by low temperature remote plasma-assisted oxidation

Monolayer N-atom incorporation at Si-SiO2 interfaces in device-quality SiO2 gate oxides has been accomplished by a three-step low-thermal budget process: (i) 300 degrees C remote plasma-assisted oxidation in N2O to form the nitrided Si-SiO2 interface: (ii) 300 degrees C remote plasma-assisted chemical vapor deposition from SiH4 and O-2 or N2O to form the oxide layer, and (iii) a 30 s 900 degrees C post-deposition rapid thermal anneal for chemical and structural relaxation. This paper reports on an extension of low-temperature plasma processing to ultra-thin gate dielectrics (< 3 nm) that is based on the first of the three steps identified above: the 300 degrees C remote plasma-assisted oxidation in O-2 or N2O. This paper: (i) highlights interrupted processing Auger electron spectroscopy measurements to monitor (a) growth rate and (b) interfacial nitrogen; (ii) discusses the reactions pathways for the plasma-assisted oxide growth process; (iii) contrasts (a) plasma-assisted and (b) furnace and rapid thermal oxidation processes. (C) 1998 Published by Elsevier Science S.A.