Two-dimensional high-performance steep transistors using Dirac-source carrier injection and high-mobility monochalcogenides
Next-generation quantum technologies demand for novel nanoelectronic devices that can operate at faster switching speed and with less energy consumption. Currently, silicon-based metal-oxide-semiconductor field-effect transistors, driven by thermionic emission, require at least 60 mV of gate voltage to increase the current by one order of magnitude at room temperature. Steep slope transistors such as tunneling transistors and ferroelectric negative capacitance transistors are capable of switching faster than the limit of 60 mV/decade, but they suffer their own challenges and issues for practical applications. To address these challenges, the proposed research focuses on investigation of a novel steep-slope device concept, known as the Dirac-source transistor, which is composed of two-dimensional graphene and emerging high-mobility monochalcogenides. Specifically, (i) fundamental understanding of a graphene-based Dirac-source carrier injection mechanism, (ii) investigation of synthesis technology and electronic properties of the monochalcogenides as the channel materials, and (iii) demonstration of a steep-slope Dirac-source transistors. The proposed solution governed by quantum mechanics on the nanometer scale is foreseen as a promising technique for extending Moore?s Law well into the quantum era. This project proposes events and involves entities across the university and local communities through close integration of research, education, and outreach programs with the focus on quantum nanomaterials and nanoelectronics. The proposed fundamental and multidisciplinary project will not only represent the state-of-the-art technology in the 2D material research field, but also provide an excellent training initiative for educating both undergraduate and graduate students, and for outreaching to K-12, women, and underrepresented minority students in STEM disciplines to fulfill the nation?s workforce needs.
As the miniaturization of complementary metal-oxide-semiconductor (CMOS) approaches its physical limitation, new technologies are critically needed to extend the performance of electronic systems in terms of power, speed, and density, etc. The proposed Dirac-source steep transistor is considered as a novel device concept, which is capable of working at a supply voltage less than 0.5 V and switching faster than the limit of 60 mV/decade. Such excellent performance is attributed to a synergetic combination of two-dimensional graphene and semiconducting monochalcogenides through the unique Dirac-source carrier injection mechanism in their van der Waals heterostructure. The research approach combines both theoretical simulation and experimental demonstration to pursue the final deliverables: (i) a fundamental understanding of the Dirac-source carrier injection mechanism; (ii) a high-resolution database and engineering principle of the emerging 2D semiconducting monochalcogenides; and (iii) a prototypical demonstration of the logic devices with steep subthreshold slope and low energy consumption. The intellectual significance of the proposed research includes providing innovative solution (Dirac-source carrier injection) to address the need of energy-efficient electronic devices, exploring the untapped potential of emerging two-dimensional semiconducting channel materials (monochalcogenides) based on their unique structure and properties, and representing a major breakthrough in quantum science and technology for extending Moore?s law well into the quantum era.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.