Method of forming very reactive metal layers by a high vacuum plasma enhanced atomic layer deposition system

Abstract

This invention provides a method and a system to deposit a thin layer of very reactive metals by plasma enhanced atomic layer deposition (PEALD). The very reactive metals, selected from the highly electropositive elements include alkaline earth metals, group III metals, and some transition and rare earth metals. The method is comprised of sequentially pulsing one of above mentioned metal containing organometallic precursors and a hydrogen plasma as a reducing agent into a high vacuum reaction chamber containing a substrate surface with pulsed or continuous flow of an inert purge gas between each pulsing step. The system comprising a very high efficiency H plasma source, the high vacuum reactor chamber, an anti-corrosion turbo pump and a high vacuum load lock is required for reducing contaminant gases such as O, HO, and CO, and for increasing hydrogen plasma efficiency.