Heterojunction Silicon Solar Cells: Recent Developments

The absolute world record efficiency for silicon solar cells is now held by an heterojunction technology (HJT) device using a fully rear-contacted structure. This chapter reviews the recent research and industry developments which have enabled this technology to reach unprecedented performance and discusses challenges and opportunities for its future industrial expansion. Silicon heterojunction devices rely on the use of thin-film silicon coatings on either side of the wafer to provide surface passivation and charge carrier-selectivity. Beyond traditional indium tin oxide, multiple higher-mobility indium-based transparent conductive oxides have been employed successfully in HJT cells. Beyond being a topic of interest for academic institutions, several companies have active research and development teams investigating HJT both at the cell and module level. Thus, silicon HJT holds a place of choice in the intense competition occurring nowadays for market supremacy in the photovoltaics world.