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In this work, n-ZnO-nanowire/p-Si junction diodes have been fabricated and characterized both physically as well as electrically. The measurements are performed on a single standalone nanowire diode for the investigation of electrical transport through the nano-junction. The rectification properties of the single n-ZnO nanowire/p-Si diode have been studied for various input waveforms and frequencies. The diodes exhibit very promising rectification as well as switching behavior with no charge storage effect and consequently, a switching time as small as ∼1 ms has been achieved.

In the current work, a design space for developing the performance enhanced strain-engineered Si nanowire field-effect-transistors has been provided. The fraction of insertion of the nanowire channel into the Insulator-on-Silicon substrate with judicious selection of high-k gate insulators is used as the key design parameter. The combined effect of fractional insertion and gate insulators results in inducing stress into the nanowire channel and, depending on their selection, it changes from tensile to compressive. Such induced-stress alters the existing inherent phononic-stress, leading to the modification of the carrier transport in the device channel. The carrier transport behavior in such partially embedded nanowire FETs has been modeled by incorporating the relevant stress-related effects into the indigenously developed self-consistent quantum-electrostatic framework. These equations are solved by employing the non-equilibrium Green's function formalism. The study shows the phonon scattering under tensile strain to occur at the expense of electron energy; however, the electrons can also gain energy during such scattering in compressive stress. Thus, the device current has been observed to increase with tensile stress and it achieves relatively smaller values when the inherent tensile phononic stress is balanced by the induced compressive stress. However, the current is finally observed to increase once the compressive stress overcomes the inherent tensile phononic stress. In general, the present devices exhibit promising Ion/Ioff ratio for all of the fractional insertions and gate dielectrics with a maximum Ioff of <10 nA/μm, threshold voltage of sub-0.3 V, gm of ∼104 µS/µm, sub-threshold swing of ∼100 mV/dec, and drain-induced-barrier-lowering of ∼100 mV/V.

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In this work, the high pressure phase of titanium dioxide (TiO2‐II) film is grown with vapor‐liquid‐solid (VLS) method on <100>‐GaAs substrate by utilizing the natural process‐induced‐strain, originating from the thermo‐elastic mismatch between TiO2 and GaAs in VLS process. The mismatches in thermal expansion coefficient and elastic constant of TiO2 and GaAs are Δα≈55% and ΔY≈170% which incorporate a substantial amount of stress (≈GPa) during cooling from the growth temperature (500 °C). SEM imaging suggests the formation of a continuous film and cross‐sectional TEM image confirmed its high crystalline quality. XRD peaks at 2θ = 31.300 and 58.670 confirm the formation of [111] and [212]‐planes of TiO2‐II phase and its chemical states are analyzed from X‐ray photoelectron spectroscopy (XPS) measurements. The bandgap of TiO2‐II phase is estimated to be 2.88 eV from cathodoluminescence study for the first time which agrees satisfactorily with the theoretical predictions reported.

This article studies the impact of doping dependent carrier effective masses of the source/drain regions on transport properties of Si-nanowire field effect transistors within ballistic limit. The difference of carrier effective mass in channel and that in the source/drain regions leads to a misalignment of respective sub-bands and forms non-ideal contacts. Such non-idealities are incorporated by modifying the relevant self-energies which control the effective electronic transport from source to drain through the channel. Non-ideality also arises in the nature of local density of states in the channel due to sub-band misalignment, resulting to a reduction of drain current by almost 50%. The highest values of drain current, leakage current, and their ratio are obtained for the S/D doping concentrations of 3 × 1020 cm−3, 8 × 1020 cm−3, and 2 × 1020 cm−3, respectively, for the nanowire of length 10 nm and diameter of 3 nm. Interestingly, the maximum of sub-threshold swing, minimum of threshold voltage, and the maximum of leakage current are observed to be apparent at the same doping concentration.