Patent ID: 8404970

Claim:
A bifacial solar cell, comprising: a silicon substrate of a first conductivity type with a front surface and a back surface; a doped region of said first conductivity type located on said back surface of said silicon substrate; a dielectric stack including aluminum oxide and silicon nitride, deposited on said doped region; an active region of a second conductivity type located on said front surface of said silicon substrate; a passivation and AR dielectric layer deposited on said active region; a first contact grid applied to said dielectric layer, said first contact grid comprised of a first metal, wherein after a firing step said first contact grid is alloyed through said dielectric stack to said doped region located on said back surface of said silicon substrate; a second contact grid applied to said passivation and AR dielectric layer, said second contact grid comprised of a second metal, wherein after said firing step said second contact grid is alloyed through said passivation and AR dielectric layer to said active region; and a groove on said front surface of said silicon substrate, said groove isolating a front surface p-n junction formed by said active region and said silicon substrate.