2D semiconductor SnP2S6 as a new dielectric material for 2D electronics

Abstract

Due to the intriguing optical and electronic properties, 2D materials are promising for next generation optoelectronic and electric device applications. Exploring new 2D materials with novel physical properties is rewarding for this area. In this work, we systematically investigated the optoelectronic properties of 2D metal thiophosphate SnP₂S₆ with a unique nanoporous structure. The intermediate bandgap makes SnP₂S₆ a good candidate for both the channel and gate dielectric materials in the transistor device. SnP₂S₆ showed good photoresponse properties. In addition, the MoS₂ transistor with SnP₂S₆ as a dielectric layer showed a high dielectric constant (≈23) and a low subthreshold slope down to 69.4 mV dec⁻¹, and it presented 0.1 pA scale leakage current, a threshold voltage as low as 1.1 V, an ON/OFF ratio reaching 10⁷ and negligible hysteresis with high stability and reproducibility. This work could open up new avenues for the discovery of new metal thiophosphate systems for future device applications.