Invited Paper EM+NS+SP+SS-WeA1
The Importance of Contact Engineering for 2D Devices

Wednesday, November 9, 2016, 2:20 pm, Room 102A

Contact resistance is one of the most important factors which could potentially limit the performance of novel electronic and optoelectronic devices based on two-dimensional (2D) materials like graphene, black phosphorus, various transition metal dichalcogenides (TMDs) like MoS₂, WSe₂ and beyond [1-3]. It is now widely accepted that metal-2D contacts are mostly Schottky barriers type [1-3]. Hence, various contact engineering strategies have been adopted to minimize the Schottky barrier height at the metal-2D interface and thereby reduce the contact resistance. In this talk I will provide a comprehensive overview of different contact engineering schemes metal work function engineering, interface engineering and phase engineering [4-6]. Additionally, I will also talk about the scalability of the contact resistance since an aggressively scaled 2D device will also have aggressively scaled contacts.

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2. Das S, Appenzeller J: WSe2 field effect transistors with enhanced ambipolar characteristics. Applied Physics Letters 2013, 103(10):103501

3. Das S, Demarteau M, Roelofs A: Ambipolar phosphorene field effect transistor. ACS nano 2014, 8(11):11730-11738.

4. Das S, Appenzeller J: Where does the current flow in two-dimensional layered systems?Nano letters 2013, 13(7):3396-3402

5. Das S, Gulotty R, Sumant AV, Roelofs A: All two-dimensional, flexible, transparent, and thinnest thin film transistor. Nano letters 2014, 14(5):2861-2866.

6. Kappera R, Voiry D, Yalcin SE, Branch B, Gupta G, Mohite AD, Chhowalla M: Phase-engineered low-resistance contacts for ultrathin MoS2 transistors. Nature materials 2014, 13(12):1128-1134.