A ferroelectric relaxor polymer-enhanced p-type WSe2 transistor

Chong Yin, Xudong Wang, Yan Chen, Dan Li, Tie Lin, Shuo Sun, Hong Shen, Piyi Du, Jinglan Sun, Xiangjian Meng, Junhao Chu, Hon Fai Wong, Chi Wah Leung, Zongrong Wang, Jianlu Wang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

18 Citations (Scopus)

Abstract

WSe2 has attracted extensive attention for p-FETs due to its air stability and high mobility. However, the Fermi level of WSe2 is close to the middle of the band gap, which will induce a high contact resistance with metals and thus limit the field effect mobility. In this case, a high work voltage is always required to achieve a large ON/OFF ratio. Herein, a stable WSe2 p-doping technique of coating using a ferroelectric relaxor polymer P(VDF-TrFE-CFE) is proposed. Unlike other doping methods, P(VDF-TrFE-CFE) not only can modify the Fermi level of WSe2 but can also act as a high-k gate dielectric in an FET. Dramatic enhancement of the field effect hole mobility from 27 to 170 cm2 V-1 s-1 on a six-layer WSe2 FET has been achieved. Moreover, an FET device based on bilayer WSe2 with P(VDF-TrFE-CFE) as the top gate dielectric is fabricated, which exhibits high p-type performance over a low top gate voltage range. Furthermore, low-temperature experiments reveal the influence of the phase transition of P(VDF-TrFE-CFE) on the channel carrier density and mobility. With a decrease in temperature, field effect hole mobility increases and approaches up to 900 cm2 V-1 s-1 at 200 K. The combination of the p-doping and gating with P(VDF-TrFE-CFE) provides a promising solution for obtaining high-performance p-FET with 2D semiconductors.

Original languageEnglish
Pages (from-to)1727-1734
Number of pages8
JournalNanoscale
Volume10
Issue number4
DOIs
Publication statusPublished - 28 Jan 2018

ASJC Scopus subject areas

  • Materials Science(all)

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