Abstract

There are difficulties associated with DC magnetron sputtering of insulating compounds such as nitrides and oxides at high rate. Such films are usually deposited from an elemental target in a reactive gas environment. It is difficult to maintain constant deposition conditions to produce stoichiometric films without progressively poisoning the cathode. Very recently there has been considerable interest in the synthesis of such films by cycling between elemental deposition by magnetron sputtering and subsequent compound synthesis by ion irradiation from an ion gun using the relevent reactive gas. Sequencing is usually on the scale of about one monolayer and the substrate is transported between the different deposition zones [1]. A somewhat similar deposition technique of alternating ion-plating was pioneered earlier by Schiller et al [2]. We report on the synthesis of silicon nitride films prepared in a similar manner but where the substrate is stationary and sequencing of the different deposition parameters is controlled by a computer. The technique will be referred to in the rest of this paper as MAGIC deposition (MAGnetron sputtering and Ion Conversion). The growth dynamics and film stress have been monitored in-situ by ellipsometry and interferometry, and the optical properties and stress are compared to those of silicon nitride films prepared by IAD and conventional magnetron sputtering.

© 1992 Optical Society of America