Carrier Type Control of WSe2Field-Effect Transistors by Thickness Modulation and MoO3Layer Doping

Changjian Zhou, Yuda Zhao, Salahuddin Raju, Yi Wang, Ziyuan Lin, Mansun Chan, Yang Chai

Research output: Journal article publicationJournal articleAcademic researchpeer-review

117 Citations (Scopus)

Abstract

KGaA, Weinheim Control of the carrier type in 2D materials is critical for realizing complementary logic computation. Carrier type control in WSe2field-effect transistors (FETs) is presented via thickness engineering and solid-state oxide doping, which are compatible with state-of-the-art integrated circuit (IC) processing. It is found that the carrier type of WSe2FETs evolves with its thickness, namely, p-type (<4 nm), ambipolar (≈6 nm), and n-type (>15 nm). This layer-dependent carrier type can be understood as a result of drastic change of the band edge of WSe2as a function of the thickness and their band offsets to the metal contacts. The strong carrier type tuning by solid-state oxide doping is also demonstrated, in which ambipolar characteristics of WSe2FETs are converted into pure p-type, and the field-effect hole mobility is enhanced by two orders of magnitude. The studies not only provide IC-compatible processing method to control the carrier type in 2D semiconductor, but also enable to build functional devices, such as, a tunable diode formed with an asymmetrical-thick WSe2flake for fast photodetectors.
Original languageEnglish
Pages (from-to)4223-4230
Number of pages8
JournalAdvanced Functional Materials
Volume26
Issue number23
DOIs
Publication statusPublished - 20 Jun 2016

Keywords

  • 2D materials
  • carrier type
  • doping
  • field-effect transistor

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Condensed Matter Physics
  • Electrochemistry

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