Year: 2016
Type: article
Abstract: The scaling of transistors to sub-10 nm dimensions is strongly limited by their contact resistance (RC). Here we present a systematic study of scaling MoS2 devices and contacts with varying electrode metals and controlled deposition conditions, over a wide range of temperatures (80 to 500 K), carrier densities (10(12) to 10(13) cm(-2)), and contact dimensions (20 to 500 nm). We uncover that Au deposited in ultra-high vacuum (∼10(-9) Torr) yields three times lower RC than under normal conditions, reaching 740 Ω·μm and specific contact resistivity 3 × 10(-7) Ω·cm(2), stable for over four months. Modeling reveals separate RC contributions from the Schottky barrier and the series access resistance, providing key insights on how to further improve scaling of MoS2 contacts and transistor dimensions. The contact transfer length is ∼35 nm at 300 K, which is verified experimentally using devices with 20 nm contacts and 70 nm contact pitch (CP), equivalent to the "14 nm" technology node.
Source: Nano Letters
Institutions: Stanford University, University of Illinois Urbana-Champaign
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Awards: G263198143, G429288550
OpenAlex ID: W2396859594
