Process for forming a graded index optical material and structures formed thereby

A process for depositing on the surface of a substrate a layer of an oxide material with a graded index of refraction and a predetermined periodic refractive index profile throughout the thickness of said layer, comprising the steps of:

• (a) providing said substrate;
• (b) providing a selected vapor phase reactant and a chosen oxygen-containing precursor which react upon inducement by radiation of a selected wavelength to form said oxide material which deposits on said substrate;
• (c) exposing said substrate to said vapor phase reactant and said oxygen-containing precursor in predetermined proportions in the presence of said radiation to form said oxide material having a first predetermined stoichiometric composition and a first predetermined index of refraction;
• (d) altering said predetermined proportions of said vapor phase reactant and said oxygen-containing precursor as a function of time in a continuous manner to correspondingly alter in a continuous manner said stoichiometric composition and said index of refraction of said oxide material deposited as a function of time and to thereby produce said graded index of refraction in said oxide material;
• and
• (e) repeating said altering of step "d" for the number of times required to produce said predetermined periodic refractive index profile throughout said thickness of said layer.

A process for depositing on the surface of a substrate a layer of a chosen substance comprising a composite of first and second chosen materials, in which the index of refraction of said layer varies in a predetermined continuous and periodic pattern as a function of the thickness of said layer, comprising the steps of:

• (a) providing said substrate;
• (b) providing first and second selected vapor phase reactants which react upon inducement by radiation of a selected wavelength to form said first chosen material which deposits on said substrate;
• (c) providing a third selected vapor phase reactant which reacts with said first selected vapor phase reactant upon inducement by radiation of said selected wavelength to form said second chosen material which deposits on said substrate;
• (d) exposing said substrate to said first, second, and third vapor phase reactants in predetermined proportions in the presence of said radiation to deposit said chosen substance having a first predetermined stoichiometric composition and a first predetermined index of refraction;
• (e) altering said predetermined proportions of said first, second, and third vapor phase reactants as a function of time in a continuous manner to correspondingly alter in a continuous manner said stoichiometric composition and said index of refraction of said chosen substance deposited as a function of time;
• and
• (f) repeating said altering of step "e" for the number of times required to produce said variation of said refractive index in said predetermined continuous and periodic pattern as a function of said thickness of said layer.