Silicon heterojunction solar cells: Techno-economic assessment and opportunities

by Arsalan Razzaq, Thomas G. Allen, Wenzhu Liu, Zhengxin Liu, Stefaan De Wolf
Perspective Year: 2022 DOI:


Razzaq, A., G. Allen, T., Liu, W., Liu, Z., De Wolf, S. 

Extra Information

Arsalan Razzaq and colleagues from KPV-Lab recently published their perspective in Joule, discussing the techno-economic barriers for the industrial adoption of silicon heterojunction technology. This work highlights critical areas that need to be addressed for enabling terawatt-scale silicon heterojunction deployment.


The ever-increasing electricity demand from renewables has stimulated growth in the photovoltaic (PV) industry. Yet, while grid parity has already been achieved in several countries, a continued decline in module prices coupled with further efficiency improvements at an annual growth rate of ∼0.5%abs are needed to sustain its market growth. Mainstream PV technologies are still based on crystalline silicon (c-Si) wafers with heavily doped regions and directly metallized contacts. However, these cause band-gap narrowing, Auger recombination losses, and contact recombination losses. Passivating contact (PC) technologies can overcome these limitations by decoupling surface passivation and contact formation requirements. Among PC technologies, amorphous silicon-based silicon heterojunction (SHJ) solar cells have established the world record power conversion efficiency for single-junction c-Si PV. Due to their excellent performance and simple design, they are also the preferred bottom cell technology for perovskite/silicon tandems. Nevertheless, SHJ technology accounts for only ∼2% of the current PV market share. In this review, we discuss the techno-economic challenges for large-volume SHJ manufacturing. In doing so, we highlight critical areas that need to be addressed for enabling terawatt-scale SHJ deployment.


Silicon photovoltaics passivating contacts silicon heterojunction