Method of passivating and stabilizing a ti-pecvd process chamber and combined ti-pecvd/tin-cvd processing method and apparatus

Abstract

A methodology is described by which a processing chamber used to deposit plasma-enhanced Ti-CVD films may be conditioned and passivated efficiently after either a wet cleaning or in-situ chemical cleaning, or after each successive deposition sequence. The technique allows a CVD process, such as, for example, a Ti-PECVD process, to recover film properties, such as resistivity, uniformity, and deposition rate, in a minimum time and following a minimum number of conditioning wafers, thereby improving the productivity of the system. The technique also maintains the stability of the system during continuous operation. This allows for the processing of thousands of wafers between in-situ cleaning of the chamber. Immediately following chamber cleaning and before performing the Ti-CVD process on wafers, the methodology includes forming a plasma with reactive gas to heat reactor components, then adding the coating material containing reactant to deposit the coating material onto the reactor components, then introducing an oxidizing or reducing gas into the chamber to stabilize the coating on the reactor parts, followed by resumption of the wafer coating process. During continuous operation in the Ti-CVD of wafers, the methodology includes introducing a mixture of Ar and H gases forming a plasma to heat reactor components where necessary, then introducing and chemically reducing TiCl to deposit Ti on the heated reactor components, then introducing oxidizing or reducing gas into the chamber for a period of time necessary to stabilize the Ti film. Preferably, N and NH are introduced and wafer passivation and reactor stabilization are performed simultaneously. Stabilization of the reactor only, and in some cases also the wafer, may use NH , H O, O or other gases.