Patent ID: 8648253
Filing Date: 2014-02-11
Classification: H01L,Y02E,Y02P

Abstract:
1. A photovoltaic device comprising a flexible substrate, a molybdenum back-contact layer, a Ib-IIIb-VIb solar absorber layer, a heterojunction partner layer, a buffer layer, a transparent top contact layer, and a metallic top contact, wherein the solar absorber layer comprises gallium and indium, copper, selenium, silver, and tellurium and has a composition graded such that portions of the absorber layer near the back-contact layer are enriched in tellurium and depleted in selenium relative to portions of the absorber layer near the heterojunction partner layer; wherein the solar absorber layer has composition graded such that portions of the absorber layer near the back-contact layer are enriched in copper and depleted in silver relative to portions of the absorber layer near the heterojunction partner layer.