Energy-Efficient Tunneling Field-Effect Transistors for Low-Power Device Applications: Challenges and Opportunities

Abstract

Conventional field-effect transistors (FETs) have long been considered a fundamental electronic component for a diverse range of devices. However, nanoelectronic circuits based on FETs are not energy efficient because they require a large supply voltage for switching applications. To reduce the supply voltage in standard FETs, which is hampered by the 60 mV/decade limit established by the subthreshold swing (SS), a new class of FETs have been designed, tunnel FETs (TFETs). A TFET utilizes charge-carrier transportation in device channels using quantum mechanical based band-to-band tunneling despite of conventional thermal injection. The TFETs fabricated with thin semiconducting film or nanowires can attain a 100-fold power drop compared to complementary metal−oxide−semiconductor (CMOS) transistors. As a result, the use of TFETs and CMOS technology together could ameliorate integrated circuits for low-power devices. The discovery of two-dimensional (2D) materials with a diverse range of electronic properties has also opened new gateways for condensed matter physics, nanotechnology, and material science, thus potentially improving TFET-based devices in terms of device design and performance. In this review, state-of-art TFET devices exhibiting different semiconducting channels and geometries are comprehensively reviewed followed by a brief discussion of the challenges that remain for the development of high-performance devices. Lastly, future prospects are presented for the improvement of device design and the working efficiency of TFETs.

Flexible electronics based on 2D transition metal dichalcogenides

“…Being the footstone of exible electronic devices, TMD-based thin-lm transistors (TFTs) have attracted intensive interest due to the tunable bandgap, high exibility, high surface area/volume ratio, and low vertical integration degree of TMDs. 180 Different from the bulk eld-effect transistors (FETs), TFTs have two dimensions where the surface states have a great impact on their switching characteristics. For example, monolayer MoS 2 shows a higher density of S vacancies than their bulk states, leading to an increased state density.…”

“…For example, monolayer MoS 2 shows a higher density of S vacancies than their bulk states, leading to an increased state density. 180 These atomic defects are potential charge traps and responsible for charge leakage. Besides, the intrinsic electron-phonon scattering, Coulomb impurities, surface roughness, charge traps, etc.…”

Comprehensive Study on High Purity Semiconducting Carbon Nanotube Extraction

“…However, continued silicon scaling is growing increasingly challenging, [1][2][3] motivating research on emerging nanotechnologies as a potential future supplement to silicon-based systems. [4][5][6][7][8][9][10][11][12] For instance, one-dimensional carbon nanotubes (CNTs) are cylindrical nanostructures comprised of a single atomic layer of carbon atoms and have exceptional electrical, mechanical and thermal properties. [1][2][3] Carbon nanotubes can be used to form carbon nanotube FETs (CNFETs), which are a leading candidate for realizing energy-efficient digital circuits.…”

Promises of Main-Group Metal Chalcogenide-Based Broken-Gap van der Waals Heterojunctions for Tunneling Field Effect Transistors

“…However, for complementary metal-oxide-semiconductor (CMOS) field effect transistors (FETs), SS cannot be smaller than kT / q ln10, which is about 60 mV per decade at room temperature . To overcome this thermal subthreshold limit, a band-to-band tunneling field effect transistor (TFET) is developed in recent years. − In contrast to conventional FETs, the primary mechanism in TFETs , is interband tunneling rather than thermal injection. Consequently, TFETs can achieve a steeper-subthreshold slope with SS < 60 mV/dev. − Accordingly, the power consumption in TFETs can be effectively decreased.…”