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FIR photon detector development starting from the extrinsic detectors for LWIR to FIR wavelengths are presented. Several other types of IR detectors, including the cut-off wavelength extension into the FIR range for quantum well infrared photodetectors (QWIPs), are summarized. Efforts in developing p-GaAs homojunction interfacial workfunction internal photoemission (HIWIP) far-infrared detectors and the most reason developments on GaAs/AlGaAs Heterojunction interfacial workfunction internal photoemission (HEIWIP) far-infrared detectors are presented.

Zinc oxide and germanium multilayer films have been deposited on glass substrate using electron beam evaporation and resistive heating system, respectively, for alternate layers. The structural optical and electrical parameters have been investigated for the deposited films. The layer formation was confirmed by employing Rutherford back-scattering technique. Optical properties exhibit quantum confinement effect by showing the separate band gaps for ZnO and Ge. Electrical conductivity increases due to combined effect of all six layers (six alternate layers of Ge and ZnO).

Self-Assembly Monolayer (SAM) technique, as a novel and developing technique for fabricating layer-by-layer nanofilm on substrates of various sizes, shapes and materials, has received more and more attention in the areas of light-emitting devices, nonlinear optical materials, conductive films, permselective gas membranes, sensors, modification of electrodes, resistance and printing technique. In comparison with other traditional methods, SAM technique has many significant advantages, including simple process, universality, formation with densely packed, well defined, highly ordered surfaces. This paper will give a review on the recent development in SAM technique.

Our present work deals with the formation and thermal behavior of a nonbulk alloy phase confined within about 8 nm across the interfaces of Au/Cu multilayer systems. These multilayers deposited on silicon and float glass by DC magnetron sputtering have been studied by secondary ion mass spectrometry (SIMS), X-ray diffraction (XRD) and cross-sectional transmission electron microscopy (XTEM). Along with the highly oriented growth of the Cu and Au layers along [111], Cu₃Au alloy was found to be present only at the Cu/Au interfaces in the nonbulk tetragonal D0₂₃ phase. Co-sputtering of Au and Cu under similar conditions produces only conventional fccCu₃Au alloy phases, suggesting that interfacial confinement plays a significant role in producing the novel Cu₃Au alloy phase in gold/copper multilayers. This novel phase is found to form only when the interfacial width is less than 10 nm. The D0₂₃ alloy phase tends to stabilize, rather than transforming to the bulk L1₂ phase, when the multilayer is vacuum-annealed at 150°C. As alloy formation spreads out of the interfaces (on vacuum annealing at 200°C), the dominant alloy is CuAu, consistent with the Cu:Au atomic ratio averaged over the multilayer.

Two sets of multilayer structures consisting of 44 alternating layers of a-SiN_x:H (~ 4 nm and 6 nm) and SiO₂ (5 nm) have been fabricated using the plasma-enhanced chemical vapor deposition (PECVD) technique. The a-SiN_x:H that has a lower bandgap forms the well layer, while the large bandgap SiO₂ forms the barrier layer. A single bulk layer of a-SiN_x:H has also been grown to serve as a reference for comparison with the multilayer structures. The samples were studied using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), spectroscopic ellipsometry (SE), and photoluminescence (PL) techniques. The SE data have been successfully fitted, and the complex refractive indices of the a-SiN_x:H in the bulk and multilayers have been determined. The effects of quantum confinement on the optical bandgap and refractive indices of a-SiN_x:H have been investigated. The results are correlated to the PL spectra of the samples.

By the use of Monte Carlo simulation, we have investigated the phase diagrams and magnetic properties of a ferrimagnetic Ising multilayer system with mixed spins (1, $1∕2$). The ground-state phase diagrams are first constructed for $T=0K$. To examine the influences of certain physical parameters of the system, namely the exchange interactions, the number of layers and the crystal field, we have studied the thermal behavior of the system magnetizations and the corresponding phase diagrams. The results obtained in this work show the existence of second- and first-order phase transitions and compensation temperatures. Moreover, we have investigated the hysteresis behavior, where the multi-loop phenomena are observed.

Developments in the understanding of how materials behave enable us to design material structures to display specified properties. We introduce multilayered materials as systems in which new properties can emerge, not found in their constituents in bulk form. The importance of transmission electron microscopy to determine structure–property relationships in nanoscale multilayers through characterization of their atomic structure is emphasized. Two examples of technologically useful multilayer systems are considered in more detail: hard coatings made from nitride multilayer films and the new structures and magnetic properties that are found in some metal multilayer systems. Finally, we discuss the future developments that are required to fully exploit the novel properties found in multilayered materials.

FIR photon detector development starting from the extrinsic detectors for LWIR to FIR wavelengths are presented. Several other types of IR detectors, including the cutoff wavelength extension into the FIR range for quantum well infrared photodetectors (QWIPs), are summarized. Efforts in developing p-GaAs homojunction interfacial work-function internal photoemission (HIWIP) far-infrared detectors and the most reason developments on GaAs/AlGaAs HEterojunction interfacial workfunction internal photoemission (HEIWIP) far-infrared detectors are presented.

Hot stamping ultra-high strength steel not only plays an important role in automotive field, but also has potential applications in the transmission line fittings industry. Combined with hot stamping technology, an innovative multilayer electric power fitting has been proposed. This paper offers a presentation of the structure of this multilayer electric power fitting, and then carries out the forming experiments of the multilayer stack structure on the independent development hot stamping mold. Considering the actual application status, mechanical performance after galvanization of the innovative power fitting was also investigated.

Since transparent conducting oxides can be as a buttom layer of complex film electrodes, electrodeposition technique may produce ZnO films depending on variety conditions and modified surface layers of substrates in electrochemical procedures. Here we invested the structure and morphologies of top ZnO layers by using modified surfaces of the substrate in the multilayer film-“ZnO-electrodeposition /ZnO(002)-sputtering /ITO/ glass”.