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arXiv · 2007.05842

Isotropic conduction and negative photoconduction in ultrathin PtSe$_2$ films

Francesca Urban·Farzan Gity·Paul K. Hurley·Niall McEvoy·Antonio Di Bartolomeo
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Abstract

PtSe$_2$ ultrathin films are used as the channel of back-gated field-effect transistors (FETs) that are investigated at different temperatures and under super-continuous white laser irradiation. The temperature-dependent behavior confirms the semiconducting nature of multilayer PtSe$_2$, with p-type conduction, a hole field-effect mobility up to 40 cm2/(Vs) and significant gate modulation. Electrical conduction measured along different directions shows isotropic transport. A reduction of PtSe$_2$ channel conductance is observed under exposure to light. Such negative photoconductivity is explained by a photogating effect caused by photo-charge accumulation in SiO$_2$ and at the Si/SiO$_2$ interface.

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Francesca Urban, Farzan Gity, Paul K. Hurley, Niall McEvoy, Antonio Di Bartolomeo. 2020-07-11. Isotropic conduction and negative photoconduction in ultrathin PtSe$_2$ films. https://doi.org/10.1063/5.0021009

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