Remote plasma-assisted deposition of gate quality oxides without the use of a preoxidation step

This paper discusses the development of a low temperature gate oxide deposi tion process using remote plasma chemical vapor deposition which, unlike ot her plasma-assisted gate oxide deposition processes, does not require a pre oxidation step, a significant limitation of those processes. An important f actor in the development of this process was the discovery that the backgro und water concentration in the deposition chamber plays a crucial role in d etermining the electrical properties of the oxide films. A likely mechanism is proposed for this effect. It is shown that by carefully controlling the background water concentration, it is possible to develop a process which does not require preoxidation, while yielding films whose electrical proper ties are comparable to those reported for other processes and, in the case of some parameters, comparable to the properties of furnace-grown oxides. T he process has been verified to be scalable down to at least 30 Angstrom. ( C) 1999 The Electrochemical Society. All rights reserved.