Ballistic two-dimensional lateral heterojunction bipolar transistor
Abstract
We propose and investigate the intrinsically thinnest transistor concept: a monolayer ballistic heterojunction bipolar transistor based on a lateral heterostructure of transition metal dichalcogenides. The device is intrinsically thinner than a field effect transistor because it does not need a top or bottom gate, since transport is controlled by the electrochemical potential of the base electrode. As is typical of bipolar transistors, the collector current undergoes a tenfold increase for each 60 mV increase of the base voltage over several orders of magnitude at room temperature, without sophisticated optimization of the electrostatics. We present a detailed investigation based on self-consistent simulations of electrostatics and quantum transport for both electrons and holes of a p -n -p device using MoS2 for the 10-nm base and WSe2 for the emitter and collector. Our three-terminal device simulations confirm the working principle and a large current modulation ION/IOFF∼108 for Δ VEB=0.5 V . Assuming ballistic transport, we are able to achieve a current gain β ∼104 over several orders of magnitude of collector current and a cutoff frequency up to the THz range. The exploration of the rich world of bipolar nanoscale device concepts in two-dimensional materials is promising for their potential applications in electronics and optoelectronics.
- Publication:
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Physical Review Research
- Pub Date:
- May 2021
- DOI:
- 10.1103/PhysRevResearch.3.023158
- arXiv:
- arXiv:2103.13438
- Bibcode:
- 2021PhRvR...3b3158L
- Keywords:
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- Condensed Matter - Mesoscale and Nanoscale Physics;
- Physics - Applied Physics;
- Physics - Computational Physics;
- Quantum Physics
- E-Print:
- Accepted for publication on Physical Review Research, 15 pages, 3 figures with subfigures