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The detrimental lateral band-to-band tunneling (L-BTBT) governing the OFF-state performance of the junctionless (JL) FETs is more pronounced in emerging Nanotube (NT) transistor architectures. This restricts the scaling of NT JLFETs irrespective of their ultimate electrostatic gate control due to additional core gate. Therefore, in this paper, we propose a symmetric intrinsic pocketed Pi-NT JLFET which has narrow intrinsic pockets on both sides of the channel region leading to a diminished L-BTBT induced lateral parasitic BJT action in the emerging NT JLFETs. Using calibrated 3-D simulations, we demonstrate that the incorporation of an intrinsic pocket decreases the OFF-state current by around 2 orders of magnitude in the Pi-NT JLFET for a gate length of 20 nm, leading to a significant ON-state to OFF-state current ratio (ION/IOFF) of 108. Furthermore, we also show an improvement in the performance of the emerging NT junctionless accumulation mode (JAM) FETs which exhibits a degraded performance compared to NT JLFETs due to enhanced L-BTBT irrespective of their higher ON-state current. The inclusion of the intrinsic pockets in NT JAMFET (Pi-NT JAMFET) reduces the L-BTBT originated OFF-state by 3 orders of magnitude for a gate length of 20 nm leading to an impressive (ION/IOFF) ratio of 108. Moreover, the proposed Pi-NT JLFET and Pi-NT JAMFET exhibit an impressive (ION/IOFF) ratio of ~ 108 and 106, respectively, with more than 4 orders of remarkable reduction in the leakage current even when the gate length is scaled to 10 nm. Additionally, the proposed architectures exhibit lower sensitivity to the gate length modulation unlike their conventional counterpart. The Pi-NT transistors exhibit superior immunity against the short channel effects of threshold-voltage roll-off due to the reduced electrostatic source/channel-to-drain coupling. Furthermore, we show that incorporating gate engineering of the dual-material gate (DMG) further enhances the performance of the Pi-NT transistor. The DMG-Pi-NT transistors exhibit an enhanced (ION/IOFF) ratio ~ 1011 achievable with the proper tuning of the dual metal gate work functions. Thus, our proposed device architecture enhances the scalability of the NT JLFETs and NT JAMFETs for realizing them in the future technology nodes.

Reverse engineering is a new technique employed in product design wherein original drawings or pertinent technical data are not available. Reverse engineering technology acquires the conceptual designs from the existing products and consequently creates digital product models. In the product design these digital products are employed with optimization principles. The investigation in this paper encompasses 3-D reconstruction of products by the reverse engineering technique and consequently identifying the deviations between the original product and the reverse engineered model. Design of experiments is a systematic study in the consideration of the governing parameters and there by arriving at the optimization stage. In this investigation response surface methodology method is employed by taking the input parameters viz noise level, smoothing level and triangle count %; and there by identified the responses namely deviation and curvature deviation occurred from the existing physical model. The deviations and curvature deviations are in the range 0.0266 to 0.0621 mm and 0.543 (54.3%) to 0.645 (64.5%) respectively which indicate that the reverse engineered freeform surface is not exhibiting significant difference when compared to the original CAD model. Response surface contours are constructed for determining the optimum process conditions.

High energy resolution fluorescence detected X-ray absorption spectroscopy is a powerful method for probing the electronic structure of functional materials. The X-ray penetration depth and photon-in/photon-out nature of the method allow operando experiments to be performed, in particular in electrochemical cells. Here, operando high-resolution X-ray absorption measurements of a BiVO4 photoanode are reported, simultaneously probing the local electronic states of both cations. Small but significant variations of the spectral lineshapes induced by the applied potential were observed and an explanation in terms of the occupation of electronic states at or near the band edges is proposed. [ABSTRACT FROM AUTHOR]

For the first time, this paper reports the quasi-static behavior and the applicability of the tunnel field effect transistor (TFET) for the on-chip electrostatic discharge (ESD) protection. ESD evaluations are performed on 28-nm fully depleted silicon-on-insulator (FDSOI), bulk TFET and compared with conventional shallow trench isolation (STI) diode using a well calibrated 3-D technology computer aided design (TCAD) device and process simulation deck. Initial design insights are obtained using the DC characteristics. The quasi-static behavior of a TFET is studied by applying transmission line pulsing (TLP) and very fast TLP (VFTLP) pulses at its drain terminal with gate shorted together and source connected to the ground. During negative TLP pulse at the drain, the TFET becomes a forward biased gated diode and exhibits reduced on-resistance compared to the STI diode. During positive TLP pulse, the tunneling current at the source-channel junction introduces a low impedance current path from drain to source compared to the blocking behavior of the STI diode. A short description of the advantages and challenges of the TFET from ESD perspective are also discussed. Finally, a new TFET ESD network is proposed and shown to exhibit multiple current paths compared to STI diode-based ESD network. From the network simulations, the proposed TFET-based ESD network is shown to exhibit better CDM response and hence providing a robust ESD solution for future system-on-chip design.

Nanotube (NT) FETs have been proposed as the most promising architecture for the ultimate scaling of FETs. However, an enhanced L-BTBT restricts their scaling. Therefore, in this paper, for the first time, we explore the application of a dual-material gate (DMG) in the emerging NT junctionless accumulation mode FETs and NT metal-oxide semiconductor FETs to alleviate the detrimental BTBT. The incorporation of DMG reduces the OFF-state current in the NTFETs by more than two orders of magnitude leading to a substantial ON-state to OFF-state current ratio (ION/IOFF) of ~106 for a gate length of 20 nm. This paper shows that the DMG architecture not only improves the static performance significantly but also leads to an enhanced dynamic performance due to a reduction in the total gate capacitance. In addition, we also provide the essential design guidelines for NTFETs in terms of the work function of the dual gates and their respective lengths. Since the NT architecture is essentially vertical, the DMG can be realized by the deposition processes facilitating the scaling of the DMG NTFETs unlike the lateral DMG FETs. Therefore, this paper provides an incentive for experimentally exploring the NTFETs for the future technology nodes.

Purpose: Albendazole is a poorly soluble drug which limits its oral bioavailability. The study was focussed to enhance the solubility by in-situ micronization. Methods: Albendazole microcrystals were prepared by solvent change method using gum karaya and hupu gum as stabilizing agents and the effect of each stabilizer on the prepared microcrystals were studied. FT-IR, DSC, XRD and SEM analysis were performed as a part of characterization studies. The formulations were evaluated for micromeritics, solubility and drug release. The microcrystals that had shown optimized properties were filled into suitable capsules. Results: The formulations showed reduction in particle size with uniform size distribution and three folds increase in drug release. The microcrystals had shown more than 100-folds increase in solubility compared to pure drug. Surface energy, enthalpy and crystalline nature of microcrystals were found to be reduced. Microcrystals containing gum karaya had shown more drug release. The filled-in capsules also showed increase in drug release rate. The solubility enhancement of albendazole microcrystals was mainly due to the surface adsorption of the stabilizing agents that led to reduction in surface energy and crystalline nature as substantiated by the DSC and XRD studies. The type of stabilizing agent had significant effect on dissolution rate. High affinity of albendazole with gum karaya led to faster drug release profiles. Conclusion: The study proved that in-situ micronization is an effective technique to enhance the solubility and dissolution rate of poorly soluble drugs like albendazole.