Patent ID: 8101858

Claim:
Chalcopyrite semiconductor based photovoltaic solar cell comprising: a metal substrate and a planar chalcopyrite semiconductor layer having opposed first and second planar sides, a planar conductive layer having opposed first and second planar sides between the metal substrate and the chalcopyrite semiconductor, a transparent i-type semiconductor layer comprising zinc oxide and having opposed first and second sides; and a diffusion barrier layer between the metal substrate and the conductive layer, wherein the diffusion barrier layer comprises MoO 3 , wherein the conductive layer has a crystal structure fitting to the crystal structure of the chalcopyrite semiconductor, wherein the chalcopyrite semiconductor comprises a p type CIS semiconductor, wherein the conductive layer comprises an n-type vanadium pentoxide; wherein the first side of the chalcopyrite semiconductor layer directly contacts the second layer of the planar conductive layer and the second side of the chalcopyrite semiconductor layer directly contact the second layer of the transparent i-type semiconductor layer.