Method of forming a high voltage silicon-on-sapphire photocell array

A method for forming a multi-cell photovoltaic circuit on an insulating substrate, comprising the steps of:

• forming a first silicon layer having a first concentration of a first dopant with a first polarity on a silicon wafer having a second concentration of a second dopant with a second polarity opposite said first polarity to create a photovoltaic junction;
• forming a second silicon layer on said first silicon layer, said second silicon layer having a third concentration of a third dopant having said first polarity, where said third concentration is greater than said first concentration of said first dopant;
• forming a silicon dioxide layer on said second silicon layer by thermal oxidation;
• bonding an insulating substrate to said silicon dioxide layer to create a bonded wafer;
• thinning said silicon wafer to form a thinned silicon layer;
• etching said bonded wafer to form a plurality of separate photodiodes having sloped sidewalls and to expose selected regions of said insulating substrate;
• forming an insulting silicon dioxide layer on said selected regions of said insulating substrate and on said separate photodiodes;
• exposing selected regions of said thinned silicon layer and regions of said second silicon layer of each of said photodiodes;
• and
• forming metal interconnects between said exposed selected regions of said thinned silicon layer of one of said photodiodes with said second silicon layer of another of said photodiodes.