HIGH-EFFICIENCY, LOW-COST SILICON-ZINC OXIDE HETEROJUNCTION SOLAR CELLS

摘要

Zinc oxide (ZnO) -Si heterostructure solar cells with an intermediate layer between the ZnO and the silicon are provided. These cells can provide reduced cost combined with enhanced performance relative to conventional silicon solar cells. By starting with a silicon substrate that is appropriately doped and subsequently depositing low cost thin film layers on top of it, a number of expensive and time consuming fabrication steps can be avoided. Additionally, the Si/ZnO band alignment provides increased open circuit voltages. Finally, the direct band gap of the ZnO contributes significantly to the solar cell external quantum efficiency in the ultraviolet region of the solar spectrum, which provides increased short circuit currents. The final devices are robust and damage resistant and have shown no performance degradation over the course of a year even without thick protective layers.