Patent ID: 8796060

Claim:
A method of producing a photovoltaic cell, the method comprising: a) doping a first surface of a semiconductive substrate with an n-dopant so as to form a first n + layer in said substrate; b) doping a second surface of said substrate with a p-dopant so as to form a p + layer in said substrate; c) removing a portion of said first n + layer from said first surface of said substrate, such that a concentration of said n-dopant remaining in said first surface of said substrate is variable throughout said first surface; d) doping said first surface of said substrate with an n-dopant so as to form a second n + layer, such that a concentration of said n-dopant in said second n + layer is variable throughout said first surface; and e) forming electrical contacts on each of said first surface and said second surface, thereby producing said photovoltaic cell, wherein said doping with said n-dopant so as to form said first n + layer and said doping with said p-dopant so as to form said p + layer is effected by: (i) applying a film comprising said p-dopant to said second surface; (ii) applying a film comprising said n-dopant to said first surface; and (iii) heating said substrate, thereby simultaneously forming said first n + layer and said p + layer.