Publication Date:
2017-08-12
Description:
The success of silicon as a dominant semiconductor technology has been enabled by its moderate band gap (1.1 eV), permitting low-voltage operation at reduced leakage current, and the existence of SiO 2 as a high-quality "native" insulator. In contrast, other mainstream semiconductors lack stable oxides and must rely on deposited insulators, presenting numerous compatibility challenges. We demonstrate that layered two-dimensional (2D) semiconductors HfSe 2 and ZrSe 2 have band gaps of 0.9 to 1.2 eV (bulk to monolayer) and technologically desirable "high-" native dielectrics HfO 2 and ZrO 2 , respectively. We use spectroscopic and computational studies to elucidate their electronic band structure and then fabricate air-stable transistors down to three-layer thickness with careful processing and dielectric encapsulation. Electronic measurements reveal promising performance (on/off ratio 〉 10 6 ; on current, ~30 μA/μm), with native oxides reducing the effects of interfacial traps. These are the first 2D materials to demonstrate technologically relevant properties of silicon, in addition to unique compatibility with high- dielectrics, and scaling benefits from their atomically thin nature.
Electronic ISSN:
2375-2548
Topics:
Natural Sciences in General
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