Cost-effective solar cells: Yangzhou University in China reduces silver use with aluminium paste

China's Yangzhou University researchers have developed a solar cell using tunnel oxide passivated contact (TOPCon) technology. This innovation significantly cuts costs by replacing the traditionally expensive silver paste with a screen-printed aluminium (Al) paste.

A spokesperson from the research team mentioned that they are still refining the innovation. However, they are currently undertaking tests with JA Solar, a leading Chinese solar module manufacturer, and Ruxing Technology Development Co. Ltd., a specialist in paste manufacturing, to test and enhance the technology.

The group constructed an 182 mm x 182 mm cell on a 140 μm n-type Czochralski wafer. The rear-side passivation contact structure was designed with a 1.6 nm silicon monoxide (SiOx) layer and a 250 nm phosphorus-doped polycrystalline silicon layer, both deposited using low-pressure chemical vapour deposition (LPCVD). Additionally, the device includes an aluminium oxide (AlOx) layer, which was applied via atomic layer deposition (ALD).