Back-contact structures for optoelectronic devices: Applications and perspectives

Abstract

Interdigitated back contact (IBC) structures formed by integrating two functional materials of opposite polarity on the rear side of device have attracted a significant attention for optoelectronic device design. Currently, this type of IBC design has been widely developed with a variety of applications in the photovoltaic (PV) community and associated fields. In terms of PV devices, the IBC designs can eliminate the need for a front electrode, endowing a potential in high power conversion efficiency. Moreover, by opening the front surface on IBC structures provides a platform for further designs, which enables us to realize a series of derived applications. This review summarizes the recent progress in IBC based PV devices, including c-Si solar cells (SCs), perovskite SCs, and perovskite/c-Si tandem SCs. Furthermore, the focus herein is focused on the latest advances in the specific applications in the studies of photon recycling, and in-situ / in-operando measurements of photoelectric properties. Finally, a perspective into the remaining challenges and future opportunities to accelerate the practical applications of IBC devices is highlighted. • A systematic review including physical mechanism and design principles is summarized. • A large number of applications for optoelectronic devices are covered, which is of great interest to not only the fundamental researchers but also to the photovoltaic industry. • The content presented in this review includes many of the latest reports and sheds new light on the device designs and characterization.