High quality TCO-silicon interface contact structure for high efficiency thin film silicon solar cells

A method of forming a photovoltaic device, comprising:

• forming a first TCO layer on a substrate;
• forming a second TCO layer disposed on and in physical contact with the first TCO layer;
• and
• forming a first p-i-n junction on the second TCO layer;
• and
• forming a degeneratively doped p-type silicon carbide layer between the second TCO layer and the first p-i-n junction, wherein the first p-i-n junction comprises:
• forming a p-type silicon containing layer over the second TCO layer, wherein the p-type silicon containing layer is a microcrystalline silicon based layer, a nanocrystalline silicon based layer or an amorphous silicon based layer, wherein the p-type silicon containing layer is a first silicon carbide layer having a carbon concentration between about 10 atomic percent and about 20 atomic percent, wherein the p-type silicon containing layer has a p-type dopant concentration between about 1×1018 atoms/cm3 and about 1×1020 atoms/cm3;
• forming an intrinsic type silicon containing layer over the p-type containing layer;
• and
• forming a n-type silicon containing layer over the intrinsic type silicon containing layer, wherein the degeneratively doped p-type silicon layer has a second p-type dopant concentration higher than the first p-type dopant concentration of the p-type silicon containing layer, wherein the second p-type dopant concentration is between 1×1020 atoms/cm3 and about 1×1021 atoms/cm3, and a p-type nanocrystalline silicon layer disposed between the second TCO layer and the degeneratively-doped p-type silicon carbide layer.