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A short channel organic field effect transistors (OFET) based on Pentacene, having channel length in the range of sub-micrometer, has been numerically modelled for low values of drain voltage. The output characteristics show a nonlinear concave increase of drain current for all values of gate voltages. This anomalous current-voltage behavior, which resembles sub-threshold characteristics of silicon FETs, shows a good match with earlier experimental reports on OFET at low drain voltages. The sub-threshold-like characteristics has been interpreted in light of thermionic-emission model because of the presence of hole injection barrier at drain (gold)/Pentacene interface. The associated analysis has facilitated to obtain a significant parameter, effective channel thickness $(t_{\mathrm{\text{eff}}})$, for the first time in case of OFETs. It came out to be roughly 4 nm and 8 nm for experimental devices of poly(3-hexylthiophene-2,5-diyl) and Pentacene, respectively, while the numerically modelled device yielded a value of about 60 nm. Increase of $t_{\mathrm{\text{eff}}}$ with transverse gate electric field is also observed. Physical explanation of the observations is also presented.

A low-power, low-supply, low-complexity all-MOSFET voltage reference is implemented in 0.18$\mu$m CMOS process. With the proposed architecture, the number of the transistors can be reduced to the greatest extent. As a result, the supply voltage can not only be decreased to as low as 0.7V, but the power consumption can also be optimized significantly. Simulation results show that the power consumption is 47nW, at a supply of 0.7V. A temperature coefficient (TC) of 42ppm/${}^{\circ }$C is achieved when the temperature ranges from $-$20${}^{\circ }$C to 80${}^{\circ }$C. At room temperature, the voltage reference features a line regulation (LR) of 2.66%/V.

In this paper, an ultra-low power CMOS voltage reference capable of operating at sub-1V input supply is proposed. Four transistors biased in weak inversion are used to generate the required complementary-to-absolute-temperature (CTAT) and proportional-to-absolute-temperature (PTAT) voltages of the proposed circuit. Self-biasing of nature of the proposed configuration in the form of operational amplifier (opamp)-free ensure nano-power operation and eliminate the need for lateral bipolar junction transistors (BJTs) and offset cancelation techniques. A prototype of the circuit is designed and simulated in a standard 0.18-$\mu$m CMOS process. Post-layout simulation results show that the circuit generates a reference voltage of 494mV with temperature coefficient (TC) of 58.4ppm/^∘C across $-40^{\circ }$C to 85^∘C; while the consuming power is lowered to 3.48nW at the minimum supply of 0.8V. The line sensitivity is 0.7%/V for the supply voltages from 0.8V to 1.8V, whereas the power supply ripple rejection (PSRR) is $-$49.06dB at 1Hz. Monte Carlo simulation results of the voltage reference show a mean value of 497.2mV with $\sigma$/$\mu$ of 1.7%, demonstrating the robustness of the generated reference voltage against the process variations and mismatch.

This paper examines the Double gate Graphene Nano-ribbon Tunnel Field-Effect Transistor (DG GNR TFET) for bio-sensing applications. The biomolecules are Streptavidin, APTES, Biotin, DNA and protein. Differentiation between biomolecules is possible based on dielectric permittivity and charge concentration. The protein switching ratio ($I_{\mathrm{\text{ON}}}$/$I_{\mathrm{\text{OFF}}})$ is 25.7 times that of Streptavidin and around 300 times that without any biomolecule in the cavity. The maximum current sensitivity among the biomolecules is achieved by protein biomolecule for VGS = 0.7V. The sub-threshold swing obtained for a biomolecule in DG GNR TFET is 40 mV/dec compared to that of 80mV/dec for an empty cavity. The device characteristics reveal that the drain current is maximum with a biomolecule in a cavity compared to an empty cavity. Results obtained emphasize that double gate Graphene Nano-Ribbon TFET is suitable as a biosensor. The simulations are executed using Silvaco Technology Computer Aided Design (TCAD).