Transition Metal Dichalcogenide-Based Field-Effect Transistors for Analog/Mixed- Signal Applications

• Published in: IEEE transactions on electron devices Vol. 66; no. 5; pp. 2424 - 2430
• Main Authors: Rawat, Brajesh, M. M., Vinaya, Paily, Roy
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-05-2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Analog circuits; Analog/RF application; black phosphorus (BP); Capacitance; Chalcogenides; Cutoff frequency; Data processing; Energy gap; Field effect transistors; field-effect transistors (FETs); Graphene; Integrated circuits; intrinsic gain; Logic gates; Molybdenum disulfide; nonequilibrium Green’s function (NEGF); oscillation frequency; Oscillators; overlap (OL); Performance evaluation; Semiconductor devices; Transistors; Transition metal compounds; transition metal dichalcogenide (TMD); underlap (UL)
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2019.2906235

Transition metal dichalcogenides (TMDs), such as MoS 2 , MoSe 2 , MoTe 2 , WS 2 , WSe 2 , etc., have been considered as the most promising candidates for energy-efficient information processing at ultrascaled devices due to their decent energy gap of around 1-2 eV and single-atomic thickness. Even though there are many efforts to explore their performance for digital applications, their performance considerations for analog/mixed-signal applications are still unexplored. In this regard, we have assessed the analog/RF performance of TMD-based field-effect transistors (TMD-FETs) and investigated their benefits over graphene-FET and black phosphorous-FETs. The performance analysis is done by an in-house developed code, which involves the self-consistent solutions of 2-D Poisson's equation and nonequilibrium Green's function (NEGF) formalism. The results show that MoS 2 -FET can offer high intrinsic gain with the intrinsic cutoff frequency and maximum oscillation frequency in terahertz range. However, the significant degradation in high-frequency performance of MoS 2 -FET is observed in the presence of external resistances and parasitic capacitances. The cutoff frequency has found a few hundreds of gigahertz range in the presence of all parasitic conditions. It has also found that, among TMD-FETs, WSe 2 -FET could be a promising candidate for analog/RF integrated circuits with a higher drive current, intrinsic gain, cutoff frequency, and maximum oscillation frequency.