Electron‐Selective Scandium−Tunnel Oxide Passivated Contact for n‐Type Silicon Solar Cells. Issue 8 (12th June 2018) - Quan, Cheng
Abstract : Dopant‐free carrier‐selective contacts have a high potential for cost reduction in solar panel production because of the simple structure and manufacturing procedure. Increasing the carrier selectivity is critical for improving the efficiency of heterostructure solar cells. Low work function metals have been explored as electron‐selective contact (ESC) recently. In this paper, a high‐performance silicon‐oxide/scandium (SiOx /Sc) ESC structure is explored as an ESC that exhibits a good contact and surface passivation. The lowest contact resistivity of 23 mΩ cm 2 and the champion single‐surface saturated dark current density ( J oe ) of 61 fA cm −2 have been achieved with a full‐area SiOx /Sc passivated contact. It was revealed that the ScOx formed by the reaction of Sc and SiOx was the critical material modifying the interfacial work function. Finally, the champion efficiency of >15% and an open circuit voltage ( V oc ) of >620 mV are achieved for the full‐area rear SiOx /Sc passivated‐contact n‐type c‐Si solar cell. A comprehensive analysis indicates that a high‐efficiency n‐type solar cell with efficiency of >20% is expected with the application of high‐efficiency structures. Abstract : Contact resistivity of 23 mΩ · cm 2 and a single‐surface saturated dark‐current density of 61 fA cm −2 are achieved with a SiOx /Sc electron‐selective contact. The formed ScOx is revealed as the material modifying the interfacial work function. The champion efficiency of >15% and an open‐circuit voltage of >620 mV are achieved for the full‐area rear SiOx /Sc passivated‐contact n‐type c‐Si solar cell.