Thermal Stable High-Efficiency Copper Screen Printed Back Contact Solar Cells
N. Chen (International Solar Energy Research Center (ISC), TU Delft - Photovoltaic Materials and Devices)
Dominik Rudolph (International Solar Energy Research Center (ISC))
Christoph Peter (International Solar Energy Research Center (ISC))
M. Zeman (TU Delft - Electrical Sustainable Energy)
O. Isabella (TU Delft - Photovoltaic Materials and Devices)
Yitzchak Rosen (Copprint Technologies Ltd.)
Michael Grouchko (Copprint Technologies Ltd.)
Ofer Shochet (Copprint Technologies Ltd.)
Valentin D. Mihailetchi (International Solar Energy Research Center (ISC))
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
The high usage of silver in industrial solar cells may limit the growth of the solar industry. One solution is to replace Ag with copper. A screen printable Cu paste is used herein to metallize industrial interdigitated back contact (IBC) solar cells. A novel metallization structure is proposed for making solar cells. Cu paste is applied to replace the majority of the Ag used in IBC cells as busbars and fingers. Cu paste is evaluated for use as fingers, and solar cells are made to test conversion efficiency and reliability. The Cu paste achieves comparably low resistivity, and Cu paste printed cells demonstrate similar efficiency to Ag paste printed cells, with an average efficiency of 23%, and only 4.5 mg W−1 of Ag usage. Also, the solar cells are stable and no Cu in-diffusion is observed under damp heat (85 °C, 85% relative humidity) and thermal stress (200 °C) for 1000 h, respectively. All processes used in this study can be carried out with industrial equipment. These findings reveal a new application for Cu pastes and point to a new direction for reducing Ag utilization and cost.