Multi-junction photovoltaic device and fabrication method

摘要

A method of forming a photovoltaic device that includes bonding a substrate to a germanium-containing semiconductor layer with a stressor layer, wherein the stressor layer cleaves the germanium-containing semiconductor layer. At least one semiconductor layer is formed on a cleaved surface of the germanium-containing semiconductor layer that is opposite the conductivity type of the germanium-containing semiconductor layer to provide a first solar cell. The first solar cell absorbs a first range of wavelengths. At least one second solar cell may be formed on the first solar cell, wherein the at least one second solar cell is composed of at least one semiconductor material to absorb a second range of wavelengths that is different than the first range wavelengths absorbed by the first solar cell.

主权项

1. A photovoltaic device comprising:
a back contact structure on an upper surface of a flexible substrate; a first solar cell present on the back contact structure, wherein the first solar cell includes a germanium-containing crystalline semiconductor layer having a thickness ranging from 100 nm to 100 μm, wherein the first solar cell absorbs a first range of wavelengths; at least a second solar cell present on the first solar cell, the at least one second solar cell is composed of at least one semiconductor material that is selected so that the second solar cell absorbs a second range of wavelengths that is different than the first range of wavelengths absorbed by the first solar cell; and a front contact structure on the upper surface of the at least one second solar cell, wherein a passivation layer, a back surface field region or a combination of a passivation layer and a back surface field region is located between the germanium containing crystalline semiconductor layer and the back contact structure that is present on the upper surface of the flexible substrate.