Ultra‐Steep Slope Impact Ionization Transistors Based on Graphene/InAs Heterostructures

Journal Article · Tue Sep 29 00:00:00 EDT 2020 · Small Structures

DOI:https://doi.org/10.1002/sstr.202000039· OSTI ID:1786625

Liu, Yuan ^[1]; Guo, Jian ^[2]; Song, Wenjing ^[3]; Wang, Peiqi ^[4]; Gambin, Vincent ^[5]; Huang, Yu ^[6]; Duan, Xiangfeng  ^[7]

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1. Department of Materials Science and Engineering University of California Los Angeles CA 90095 USA, School of Physics and Electronics Hunan University Changsha 410082 China
2. Department of Materials Science and Engineering University of California Los Angeles CA 90095 USA
3. School of Physics and Electronics Hunan University Changsha 410082 China
4. Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
5. NG NEXT Northrop Grumman Aerospace Systems Redondo Beach CA 90278 USA
6. Department of Materials Science and Engineering University of California Los Angeles CA 90095 USA, California Nanosystems Institute University of California Los Angeles CA 90095 USA
7. Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA, California Nanosystems Institute University of California Los Angeles CA 90095 USA

With the continued scaling of transistors, there is a growing trend for developing steep slope transistors with subthreshold swing (SS) below Boltzmann limitation ( k T/ q ). To this end, impact ionization metal oxide semiconductor (I‐MOS) transistors are attractive for a unique combination of high ON‐state current density, small hysteresis, and ultra‐steep SS slope. However, the performance of I‐MOS is generally limited by the relatively thick depletion region and large operation voltage required for the activation of impact ionization (typically >5 V). Herein, a high‐performance I‐MOS is constructed by van der Waals integrating single‐crystal InAs film with graphene. Due to the low bandgap of InAs as well as the semi‐metallic nature of graphene, the InAs/graphene I‐MOS demonstrates a low operation voltage of 1.5 V, high ON‐state current of 230 μA μm ⁻¹ , steep SS <0.6 mV dec ⁻¹ , and large ON–OFF ratio >10 ⁶ at temperature below 200 K. Furthermore, a negative transconductance and steep current oscillation is observed in the subthreshold regime, and a device working mechanism is proposed for this novel phenomenon. This study not only pushes the performance limit of I‐MOS but also defines a general pathway to van der Waals heterostructures between conventional III–V compound semiconductors and novel 2D materials for unconventional device functions.

• Sponsoring Organization: USDOE
• OSTI ID: 1786625
• Journal Information: Small Structures, Journal Name: Small Structures Vol. 2 Journal Issue: 1; ISSN 2688-4062
• Publisher: Wiley Blackwell (John Wiley & Sons)
• Country of Publication: Germany
• Language: English