Intriguing field-effect-transistor performance of two-dimensional layered and crystalline CrI3

• Published in: Materials today physics Vol. 12; p. 100174
• Main Authors: Patil, Ranjit A., Tu, Hao-Wei, Jen, Ming-Hsing, Lin, Jing-Jia, Wu, Ching-Cherng, Yang, Chun-Chuen, Pham, Duy Van, Tsai, Chih-Hung, Lai, Chien-Chih, Liou, Yung, Jian, Wen-Bin, Ma, Yuan-Ron
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.03.2020
• Subjects: Chromium triiodide; Field effect transistors; Large-area; Two-dimensional materials; Two-dimensional materials; 2D; Field effect transistors; FESEM; AFM; XPS; Large-area; XRD; OM; FETs; Chromium triiodide
• ISSN: 2542-5293; 2542-5293
• DOI: 10.1016/j.mtphys.2019.100174

There are many candidate materials that can be used as channel materials for the next-generation field effect transistors (FETs). CrI3 is one of the particular candidates for application in FET, because it is a two-dimensional (2D) ferromagnet and has giant tunneling magnetoresistance. The ferromagnetic nature extends to not only electronics but also spintronics. In this study, the large-area, layered, and crystalline 2D CrI3 were synthesized by horizontal Bridgman method. The suspended CrI3 FETs were fabricated for explorations of intrinsic electron transport in the CrI3 channel and of electrical contact problems. The suspended FET structure lets the CrI3 channel free from trapping charges in the SiO2-capped Si substrate. The on–off ratio of the suspended CrI3 FET is up to 104, making the 2D layered CrI3 potential for future FETs. The investigations of the mobility and the interface-trap density at various temperatures reveal that the trapping charges as well as the interface-trap densities are increased with further gas adsorption on the surface of the CrI3 flake. The performance of the suspended CrI3 FET can be improved, if the gas adsorption problem can be carefully treated. [Display omitted] •The 2D layered CrI3 single crystals are not only ferromagnets but also semiconducting materials.•The 2D layered CrI3 single crystals can be exfoliated into thin 2D layered CrI3 flakes.•The thin 2D layered CrI3 flakes are exploited to produce a suspended CrI3 field-effect-transistor device.•The suspended CrI3 FET device has unique field-effect performance.