In-Sn Oxide Bilayer Transparent Conductive Film by DC Magnetron Sputtering for Silicon Heterojunction Solar Cells

The optical and electrical properties of the front transparent conductive film of a heterojunction with intrinsic thin-layer solar cell are the key factors that determine the photovoltaic conversion efficiency of the device. First, the relationship between the structure as well as optoelectronic properties and sputtering process of ITO-97/3 (In
₂
O
₃
:SnO
₂
= 97 wt.%:3 wt.%) thin film with low SnO
₂
content and conventional ITO-90/10 (In
₂
O
₃
:SnO
₂
= 90 wt.%:10 wt.%) thin film was compared and studied in this article. Next, the application of ITO-97/3 thin film for heterojunction with intrinsic thin-layer solar cells was verified. It was found that, although the spectral response was improved, the series resistance of the device deteriorated. Finally, the bilayer structure of ITO-90/10 and ITO-97/3 was introduced into a heterojunction with intrinsic thin-layer solar cell. The results showed that the overall performance of the device was improved because of the combination of electrical and optical characteristics of the bilayer.