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A compact monolithic trantenna (transistor-antenna) device is presented for a high-performance sub-THz wave detector using 28-nm CMOS foundry process. Based on a highly localized plasmonic wave in a silicon nano-ring field-effect transistor (FET), we obtained a total 535-fold photoresponse (Δu) enhancement in an on-chip measurement as compared with our previous works using the same asymmetry ratio (ηa= 30). The inner contact diameter (din) was scaled down from 8 to 0.13 μm for the parasitic resistance limit case. By changing the ground source from inside to outside the nano-ring FET, we could generate different Δu polarities, which in turn reduced the junction leakage with improved |Δu|. From a fabricated nano-ring FET with the outer ring grounded source, we observed 5× of additional |Δu| enhancement followed by 107× with din scaling. In addition, based on the highly localized plasmonic wave nano-ring FET without any external gain, a record-high free-space responsivity of 12.4 kV/W and a reduced noise equivalent power of 1 pW/Hz0.5 were experimentally demonstrated under 0.12-THz radiation.

Ferroelectric tunnel junction (FTJ) exploiting the switchable polarization of ferroelectric material holds great potential for the low-power non-volatile memory. Recently, two-dimensional (2D) ferroelectric material CuInP2S6 (CIPS) which can provide ferroelectricity at the ultimate atomic-scale has been successfully introduced in FTJ to achieve significantly improved TER. Here, we present a theoretical study on the performance of FTJ based on CIPS through the quantum transport simulation using kp Hamiltonian obtained from density functional theory. Benchmarking with ferroelectric HfZrO2-based FTJ reveals that much higher TER can be achieved in CIPS-based FTJ due to a lower tunneling potential barrier and a larger tunneling effective mass.

We present scaling and variation predictions for a strained-silicon (s-Si) fin-based high electron mobility transistor (FinHEMT) with well-tempered, short-channel characteristics. Using device simulation calibrated with experimental data, we predict that the FinHEMT can achieve high electron mobility (~1100 cm2/Vs) and enhance effective mobility (up to 2x) by suppressing the surface roughness scattering effect in the Si quantum well (QW) channel. Moreover, excellent scalability of the FinHEMT ON-current ( ${I}_{{\textit {ON}}} >1.1$ mA/ $\mu \text{m}$ at ${L}_{G} nm) is predicted as the high channel mobility can reduce the underlap series resistance in the scaled device. Owing to this low underlap resistivity, geometrical variations of fin width and underlap length have little effect on the ON-current in FinHEMT.

We propose a logic synthesis methodology with a novel low-power circuit structure for ternary logic. The proposed methodology synthesizes a ternary function as a ternary logic gate using carbon nanotube field-effect transistors (CNTFETs). The circuit structure uses the body effect to mitigate the excessive power consumption for the third logic value. Energy-efficient ternary logic circuits are designed with a combination of synthesized low-power ternary logic gates. The proposed methodology is applicable to both unbalanced (0, 1, 2) and balanced (−1, 0, 1) ternary logic. To verify the improvement in energy efficiency, we have designed various ternary arithmetic logic circuits using the proposed methodology. The proposed ternary full adder has a significant improvement in the power-delay product (PDP) over previous designs. Ternary benchmark circuits have been designed to show that complex ternary functions can be designed to more efficient circuits with the proposed methodology.

This article reports a novel monolithic circular transistor-antenna by designing a ring-type asymmetric field-effect transistors (FET) itself as a receiving antenna element for high-performance plasmonic millimeter-wave detectors. Operation principle of the proposed device is discussed, focusing on how signal transmission through the ring-type structure is available without any feeding line between the antenna and the detector. To determine the antenna geometry aiming for a desired resonant frequency, we present an efficient design procedure based on periodic bandgap analysis combined with parametric electromagnetic simulations. From a fabricated ring-type FET-based monolithic antenna device for 120 GHz resonance frequency with the 3 dB full width at half maximum (FWHM) of 23 GHz, we demonstrated the highly enhanced optical responsivity ~1.1 kV/W ( $\times 5.5$ ) and the reduced optical noise equivalent power (NEP) ~18 pW/Hz0.5 ( $\times 1/7.4$ ) at a chopping frequency of 2 kHz, compared to a reference bar-type detector. Moreover, the responsivity and the NEP in this article are in comparable order with the reported values of ~2.2 kV/W and 14 pW/Hz0.5, respectively, from the state-of-the-art CMOS-based antenna integrated direct detectors.

We proposed a physical model for ink-jet printed polymeric thin-film transistors (PTFTs) all over the sub- and above-threshold regions by using an effective carrier density. The nonlinearity under the low lateral electric field in the printed thiophene PTFTs was reproduced by applying the back-to-back Schottky diode model based on simple Poole–Frenkel (PF) mobility formalism. The analytical ${I}{-}\!{V}$ model supplemented with ${C}{-}\!{V}$ model in a single framework was also verified by successfully reproducing the measured characteristics of TFTs with three different thiophene polymeric channel materials. Additionally, we applied the physics-based analytical model on the inkjet-printed PTFT-based inverter and confirmed that the proposed models could predict the inverter circuit characteristics of the gain and static noise margin (SNM) based on the physical parameters.

The power density limits of complementary metal–oxide–semiconductor (CMOS) technology could be overcome by moving from a binary to a ternary logic system. However, ternary devices are typically based on multi-threshold voltage schemes, which make the development of power-scalable and mass-producible ternary device platforms challenging. Here we report a wafer-scale and energy-efficient ternary CMOS technology. Our approach is based on a single threshold voltage and relies on a third voltage state created using an off-state constant current that originates from quantum-mechanical band-to-band tunnelling. This constant current can be scaled down to a sub-picoampere level under a low applied voltage of 0.5 V. Analysis of a ternary CMOS inverter illustrates the variation tolerance of the third intermediate output voltage state, and its symmetric in–out voltage-transfer characteristics allow integrated circuits with ternary logic and memory latch-cell functions to be demonstrated. Quantum-mechanical band-to-band tunnelling can be used to create an energy-efficient ternary logic technology that can be fabricated on the wafer scale using complementary metal–oxide–semiconductor (CMOS) processes.

A quantum confined transport based on a zinc oxide composite nanolayer that has conducting states with mobility edge quantization is proposed and was applied to develop multi-value logic transistors with stable intermediate states. A composite nanolayer with zinc oxide quantum dots embedded in amorphous zinc oxide domains generated quantized conducting states at the mobility edge, which we refer to as “mobility edge quantization”. The unique quantized conducting state effectively restricted the occupied number of carriers due to its low density of states, which enable current saturation. Multi-value logic transistors were realized by applying a hybrid superlattice consisting of zinc oxide composite nanolayers and organic barriers as channels in the transistor. The superlattice channels produced multiple states due to current saturation of the quantized conducting state in the composite nanolayers. Our multi-value transistors exhibited excellent performance characteristics, stable and reliable operation with no current fluctuation, and adjustable multi-level states., Designing multi-value logic transistors with stable and reliable intermediate states remains a challenge. Here, the authors report the mobility edge quantization phenomenon via resonant hybridization of ZnO QDs embedded in amorphous ZnO domains to enable adjustable multi-value intermediate states.

For increasing the restricted bit-density in the conventional binary logic system, extensive research efforts have been directed toward implementing single devices with a two threshold voltage (VTH) characteristic via the single negative differential resistance (NDR) phenomenon. In particular, recent advances in forming van der Waals (vdW) heterostructures with two-dimensional crystals have opened up new possibilities for realizing such NDR-based tunneling devices. However, it has been challenging to exhibit three VTH through the multiple-NDR (m-NDR) phenomenon in a single device even by using vdW heterostructures. Here, we show the m-NDR device formed on a BP/(ReS2 + HfS2) type-III double-heterostructure. This m-NDR device is then integrated with a vdW transistor to demonstrate a ternary vdW latch circuit capable of storing three logic states. Finally, the ternary latch is extended toward ternary SRAM, and its high-speed write and read operations are theoretically verified.

The N-Myc downstream-regulated gene (NDRG) family belongs to the &alpha, /&beta, hydrolase fold and is known to exert various physiologic functions in cell proliferation, differentiation, and hypoxia-induced cancer metabolism. In particular, NDRG3 is closely related to proliferation and migration of prostate cancer cells, and recent studies reported its implication in lactate-triggered hypoxia responses or tumorigenesis. However, the underlying mechanism for the functions of NDRG3 remains unclear. Here, we report the crystal structure of human NDRG3 at 2.2 &Aring, resolution, with six molecules in an asymmetric unit. While NDRG3 adopts the &alpha, hydrolase fold, complete substitution of the canonical catalytic triad residues to non-reactive residues and steric hindrance around the pseudo-active site seem to disable the &alpha, hydrolase activity. While NDRG3 shares a high similarity to NDRG2 in terms of amino acid sequence and structure, NDRG3 exhibited remarkable structural differences in a flexible loop corresponding to helix &alpha, 6 of NDRG2 that is responsible for tumor suppression. Thus, this flexible loop region seems to play a distinct role in oncogenic progression induced by NDRG3. Collectively, our studies could provide structural and biophysical insights into the molecular characteristics of NDRG3.

Ternary logic circuit has been studied for several decades because it can provide simpler circuits and subsequently lower power consumption via succinct interconnects. We demonstrated a ternary full adder exhibiting a low power-delay-product of ~10−16 J, which is comparable to the binary equivalent circuit. The ternary full adder was modeled using device parameters extracted from the experimentally demonstrated multi-Vth ternary graphene barristors.

This paper reports the effect of the source/drain junction area on the responsivity of a metal-oxide field-effect transistor (MOSFET)-based terahertz (THz) detector. From the numerical analysis based on the distributed-channel model for the plasma-wave detection mechanism, it is predicted that both the responsivity and noise-equivalent power (NEP) are improved with a relatively larger source junction area than drain junction area. For experimental verification, three types of MOSFET detectors with different source/drain junction areas are fabricated with 65-nm CMOS technology. From on-wafer measurement at 0.3 THz, 2.57 times enhanced responsivity and 63% reduced NEP have been obtained in the sample with the smallest drain junction area and the largest source junction area.

We propose a novel optimized design strategy by considering the correlated effects of highk gate oxide and spacer dielectric on GIDL and DIBL for high performance nanoscale CMOS with III-V/Ge channel tri-gate FinFET structure. By investigating the transition of GIDL mechanism from vertical to lateral direction in 14-nm InAs n-FinFET and Ge p-FinFET with abrupt and high drain doping, the lateral GIDL is suppressed as 1/100 by high-k spacer with high drive current of 1 mA/um and lower leakage current than 100 nA/um which works on lower operation voltage (VDD= 0.63 V). in addition, DIBL is also suppressed below 100 mV/V by taking relatively lower-k gate oxide than the high-k spacer.

In this paper, we propose a small, low cost force sensor based on a commercially available photointerrupter for use in a tendon-driven robotic hand. The proposed sensor consists of a photointerrupter and an elastic frame and is designed to measure tendon tension. Using the design methodology presented in this paper, the force sensor can be made small enough (4 mm × 6 mm × 10 mm) to be inserted into a robotic fingertip and made able to measure a large allowable force (approximately 200 N) with low non-linearity (1.85%) and low hysteresis (1.19%). Due to the characteristics of the photointerrupter, it is possible to overcome the disadvantages associated with traditional miniature force sensors and to have very high resolution (0.1 N) over the entire measurement range (0–200 N). To verify feasibility, we performed force feed-back control using a prototype of the sensor. Experimental results show that the proposed sensor has comparable performance to commercial force sensors of similar size and can be manufactured more simply and economically.

Demand for high throughput manufacturing has recently increased in various fields, such as electronics, photonics, optical devices, and energy. Moreover, flexible electronic devices are indispensable in applications such as touch screens, transparent conductive electrodes, transparent film heaters, organic photovoltaics, organic light-emitting diodes, and battery. For these applications, a large-area roll-to-roll (R2R) process is a promising method for producing with high throughput. However, bending deformation of rollers is unavoidable in a large-scale R2R system, which produces non-uniformity in force distribution during processing and reduces the sample quality. In this study, we propose a new R2R imprinting module to mitigate the deformation by using an additional backup roller to achieve uniform force distribution. From numerical simulations, we found that there exists an optimal imprinting force for each backup roller length to obtain the best uniformity. Experimental results using a large-area pressure sensor verified the effectiveness of the proposed method. Finally, the R2R nanoimprint lithography process showed that the proposed method produces patterns of 100 nm width with uniform residual layer thickness, which are distributed across the substrate of 1.2 m width.

The importance of the reliability of gate oxide materials is increasing continuously as CMOS technology advancing. Joule heating to induce localized high temperature via a built-in gate heater has recently been introduced as a rapid and efficient method to cure instances of gate oxide damage, including damaged interface traps and bulk traps in the gate oxide. In this paper, spatially distributed deep oxide traps were generated by Fowler–Nordheim (FN) stress, and a recovery process by electrothermal annealing (ETA) using local Joule heat was clearly demonstrated with low-frequency (LF) noise characteristics. The generation and recovery of the oxide traps were quantitatively analyzed with LF noise, and the results showed that the border traps generated by the FN stress were cured by ETA. The recovery process was predominantly affected by the applied gate voltage and the duration. Excessive gate voltage beyond the critical value permanently destroyed the gate oxide. The effect of a forming gas annealing (FGA) process on the gate oxide traps was also analyzed with LF noise and compared with that of ETA. Although electrical Joule heating was applied under a condition of ambient air, not hydrogen-rich atmosphere, the passivation effect was superior to that of a FGA process conducted in diluted H2 ambient.

The pneumatic actuator has high potential as an actuator for mobile devices due to its high power density, simplicity, compactness, light weight, and low cost. Moreover, inherent compliance of the pneumatic actuator improves safety and dynamic performance, which are strongly required for wearable robots. However, due to its need for a bulky air compressor, which is intended for stationary use, it is hard to apply a pneumatic actuator to mobile robots. To replace the air compressor, pneumatic energy sources utilizing chemical fuel were previously proposed and the potential of the hydrogen peroxide as a pneumatic energy source was proved. Nevertheless, pneumatic energy sources driven by hydrogen peroxide are generally bulky, which are hard to apply for a mesoscale system such as prosthetics. To address this challenge, this paper proposes novel pneumatic power generator driven by hydrogen peroxide. By applying a passive injection component and a mechanical pressure feedback mechanism, the pneumatic power generator regulates pressure by itself, without any control efforts, which results in compact size. In addition, a separated catalytic reactor and a fuel tank guarantee safety and mobility. The performances and energetic characteristics of the proposed pneumatic power generator are examined by both experiment and mathematical modeling.

This paper presents a novel pneumatic generator based on the catalytic decomposition of hydrogen peroxide for producing the pressurized gas for mobile robotic systems driven by pneumatic actuators, thus replacing portable air compressors driven by electric motors. By adopting a pressure-feedback mechanism, hydrogen peroxide is autonomously self-injected into the catalytic reactor without the use of additional injection mechanisms such as electric micropumps. Additionally, the dynamic behavior of pressure generation is illustrated by both an analytic model and experiments. It is experimentally demonstrated that the proposed system has a considerably higher power density than a battery and electrical motor system.

Glutathione (GSH) degradation plays an essential role in GSH homeostasis, which regulates cell survival, especially in cancer cells. Among human GSH degradation enzymes, the ChaC2 enzyme acts on GSH to form 5-l-oxoproline and Cys-Gly specifically in the cytosol. Here, we report the crystal structures of ChaC2 in two different conformations and compare the structural features with other known &gamma, glutamylcyclotransferase enzymes. The unique flexible loop of ChaC2 seems to function as a gate to achieve specificity for GSH binding and regulate the constant GSH degradation rate. Structural and biochemical analyses of ChaC2 revealed that Glu74 and Glu83 play crucial roles in directing the conformation of the enzyme and in modulating the enzyme activity. Based on a docking study of GSH to ChaC2 and binding assays, we propose a substrate-binding mode and catalytic mechanism. We also found that overexpression of ChaC2, but not mutants that inhibit activity of ChaC2, significantly promoted breast cancer cell proliferation, suggesting that the GSH degradation by ChaC2 affects the growth of breast cancer cells. Our structural and functional analyses of ChaC2 will contribute to the development of inhibitors for the ChaC family, which could effectively regulate the progression of GSH degradation-related cancers.

We demonstrate a record-high performance monolithic trantenna (transistor-antenna) using 65-nm CMOS foundry in the field of a plasmonic terahertz (THz) detector. By applying ultimate structural asymmetry between source and drain on a ring FET with source diameter $(d_{\text{S}})$ scaling from 30 to $0.37\mu \text{m}$ , we obtained 180 times more enhanced photoresponse $(\Delta u)$ in on-chip THz measurement. Through free-space THz imaging experiments, the conductive drain region of ring FET itself showed a frequency sensitivity with resonance frequency at 0.12 THz in $0.09\sim 0.2$ THz range and polarization-independent imaging results as an isotropic circular antenna. Highly-scalable and feeding line-free monolithic trantenna enables a high-performance THz detector with responsivity of 8.8 kV/ $W$ and NEP of $3.36\text{pW}/\text{Hz}^{05}$ at the target frequency.

We report the nonresonant plasmonic terahertz (THz) wave detector based on the silicon (Si) field effect transistor (FET) with a technology computer-aided design (TCAD) platform. The plasma wave behavior has been modeled by a quasi-plasma electron box as a two-dimensional electron gas (2DEG) in the channel of the FET. The incoming alternating current (AC) signal as the THz wave radiation can induce the direct-current (DC) voltage difference between the source and drain, which is called the photoresponse. For accurate analysis of the modulation and propagation of the channel electron density as the plasma wave, we have characterized the quasi-plasma 2DEG model with two key parameters, such as quasi-plasma 2DEG length (I(QP)) and density (N(QP)). By using our normalization method, I(QP) and N(QP) is defined exactly as extracting the average point of the electron density. We also investigate the performance enhancement of the plasmonic terahertz wave detector based on Si FET by scaling down the gate oxide thickness (t(ox)), which is a significant parameter of FET-based plasmonic terahertz detector for the channel electron density modulation. According to scaling down t(ox), the responsivity (R(v)) and noise equivalent power (NEP), which are the important performance metrics of the THz wave detector, have been enhanced. The proposed methodologies will provide the advanced physical analysis and structural design platform for developing the plasmonic terahertz detectors operating in nonresonant regime.

We propose a novel double-peak negative differential resistance (NDR) characteristic at the conventional single-peak MOS-NDR circuit by employing ambipolar behavior of TFET. The fluctuated voltage transfer curve (VTC) from ambipolar inverter is analyzed with simple model and successfully demonstrated with TFET, as a practical example, on the device simulation. We also verified that the fluctuated VTC generates additional peak and valleys on NDR characteristics by using circuit simulations. Moreover, by adjusting the threshold voltage of conventional MOSFET, ultra-high 1st and 2nd peak-to-valley current ratio (PVCR) over 10(7) is obtained with fully suppressed valley currents. The proposed double-peak NDR circuit expected to apply on faster switching and low power multi-functional applications.

We present covalently self-assembled peptide hollow nanocapsule and peptide lamella. These biomimetic dityrosine peptide nanostructures are synthesized by one-step photopolymerization of a tyrosine-rich short peptide without the aid of a template. This simple approach offers direct synthesis of fluorescent peptide nanocages and free-standing thin films. The simple crosslinked peptide lamella films provide robust mechanical properties with an elastic modulus of approximately 30 GPa and a hardness of 740 MPa. These nanostructures also allow for the design of peptidosomes. The approach taken here represents a rare example of covalent self-assembly of short peptides into nano-objects, which may be useful as microcompartments and separation membranes.

We report a high-performance plasmonic terahertz (THz) detector based on an antenna-coupled asymmetric FET by using the 65-nm CMOS technology. By designing an asymmetric FET on a self-aligned poly-Si gate structure, more enhanced channel charge asymmetry between the source and the drain has been obtained in comparison with the nonself-aligned metal gate structure of our previous paper. In addition, using a vertically integrated patch antenna, which is designed for a 0.2-THz resonance frequency, we demonstrated the highly enhanced detection performance with a responsivity of 1.5 kV/W and a noise-equivalent power of 15 pW/Hz0.5 at 0.2 THz.