Patent ID: 11876140
Assignee: FIRST SOLAR, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  C  Y | IPC C  H

Claim 11:
12. A photovoltaic device, comprising:
a layer stack; and
an absorber layer disposed directly in contact with the layer stack at a front interface of the absorber layer, the absorber layer consisting of a thickness between the front interface and a back interface of the absorber layer, wherein:
the absorber layer comprises a compound of cadmium, selenium, and tellurium,
an atomic concentration of selenium varies continuously across the thickness of the absorber layer,
the atomic concentration of selenium is greater at the front interface of the absorber layer relative to the back interface of the absorber layer,
the photovoltaic device has no window layer and is substantially free of a cadmium sulfide layer, and
the photovoltaic device includes a layer comprising: cadmium tin oxide, indium tin oxide; fluorine-doped tin oxide; indium-doped cadmium-oxide; doped zinc oxide, indium-zinc oxide, or zinc tin oxide.