Abstract

There is an increasing interest in nitride and oxynitride coatings of silicon for optical and microelectronic applications. Silicon oxynitride has an index of refraction that can be varied between 2.1 and 1.45 by varying the oxygen-to-nitrogen ratio.¹ The fabrication of graded-index optical components, such as graded index antireflection coatings and rugate filters, is an important application of this technology. The ability to tailor the index of refraction has been realized by applying of ion beams to the optical-coating deposition process. We have been able to deposit silicon oxynitride coatings with indices of refraction varying between 2.1 and 1.45. We will present results of optical, mechanical, and chemical characterizations and examples of applications for graded-index coatings in the deposition of graded-index antireflection coatings and rugate filters.

© 1990 Optical Society of America