Photoconductive Effects in Single Crystals of BaZrS$_3$

Boyang Zhao; Huandong Chen; Ragib Ahsan; Fei Hou; Eric R Hoglund; Shantanu Singh; Huan Zhao; Han Htoon; Andrey Krayev; Maruda Shanmugasundaram; Patrick E Hopkins; Jan Seidel; Rehan Kapadia; Jayakanth Ravichandran

arXiv · 2310.03198

Photoconductive Effects in Single Crystals of BaZrS$_3$

Boyang Zhao·Huandong Chen·Ragib Ahsan·Fei Hou·Eric R Hoglund·Shantanu Singh·Huan Zhao·Han Htoon·Andrey Krayev·Maruda Shanmugasundaram·Patrick E Hopkins·Jan Seidel·Rehan Kapadia·Jayakanth Ravichandran

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Abstract

Chalcogenide perovskites, such as BaZrS$_3$, are emerging semiconductors with potential for high photovoltaic power conversion efficiency. The role of defects in the efficiency of the generation and collection of photo-excited carriers has not been experimentally investigated extensively. We study the effect of processing-induced defects on the photoconductive properties of single crystals of BaZrS$_3$. We achieved ohmic contacts to single crystals of BaZrS$_3$ and observed positive surface photovoltage, which is typically observed in p-type semiconductors. However, mechanical polishing of BaZrS$_3$ to remove the surface oxide leads to dense deformation grain boundaries and leads to trap-dominated photoconductive response. In comparison, ohmic contacts achieved in cleaved crystals leave fewer deformation defects and greatly improve optoelectronic properties. Defect-controlled crystal growth and contact fabrication are potentially limiting factors for achieving high photon-to-excited electron conversion efficiency in BaZrS$_3$.

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Boyang Zhao, Huandong Chen, Ragib Ahsan, Fei Hou, Eric R Hoglund, Shantanu Singh, Huan Zhao, Han Htoon, Andrey Krayev, Maruda Shanmugasundaram, Patrick E Hopkins, Jan Seidel, Rehan Kapadia, Jayakanth Ravichandran. 2023-10-04. Photoconductive Effects in Single Crystals of BaZrS$_3$. https://arxiv.org/abs/2310.03198

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