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A novel technology for a multichip module (MCM) on silicon is presented. The technology features the integration of a power and a ground plane, resulting in a five‐conductor layer module, the use of the heavily (n⁺) doped Si as the ground plane for integrated decoupling capacitances, integrated low TCR NiCr resistors, low resistance (13mΩ per square) TiW/Cu/TiW metallisation, high quality PECVD oxynitride (SiON) insulation layers, which are optimised to a low stress content, and a new wet‐dry etch technique for the vias. The module is able to handle 200MHz clock frequencies and, when carefully designed, can also be used for opto‐electronic interconnections in the GHz range. A test module for DC and HF characterisation has been designed and produced. Preliminary test results are presented.

The purpose of this study is to directly measure and determine the Si/SiO2/AlOxNy interface state density on metal insulator semiconductor field effect transistor (MISFET) structures. The primary advantage of using aluminum oxynitride (AlOxNy) is the perfectly controlled variability of the properties of these layers depending on their stoichiometry, which can be easily controlled by the parameters of the magnetron sputtering process. Therefore, a continuous spectrum of properties can be achieved from the specific values for oxide to the specific ones for nitride, thus opening a wide range of applications in high power, high temperature and high frequency electronics, optics and sensors and even acoustic devices.

The basic subject of this study is n-channel transistors manufactured using silicon with 50-nm-thick AlOxNy films deposited on a silicon dioxide buffer layer via magnetron sputtering in which the gate dielectric was etched with wet solutions and/or dry plasma mixtures. Furthermore, the output, transfer and charge pumping (CP) characteristics were measured and compared for all modifications of the etching process.

An electrical measurement of MISFETs with AlOxNy gate dielectrics was conducted to plot the current-voltage and CP characteristics and examine the influence of the etching method on MISFET parameters.

In this report, a flat band and threshold voltage and the density of interface traps were determined to evaluate and improve an AlOxNy-based MISFET performance toward highly sensitive field effect transistors for hydrogen detection by applying a Pd-based nanocrystalline layer. The sensitivity of the detectors was highly correlated with the quality of the etching process of the gate dielectrics.

Aluminium nitride (AlN) is currently under investigation as a substrate material for use in microcircuit applications in particular where high thermal conductivity is required. Three commercially available substrate materials have been characterised using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The differences in thermal conductivity between the materials and also the difference from the theoretical thermal conductivity have been correlated to the presence of low thermal conductivity second phase regions between grains, defects within the crystal structure, the presence of oxygen impurities and poor sintering behaviour. The highest thermal conductivity substrate obtainable during this study was 140 W7m K. The substrates were identified as comprising hexagonal AIM having a wurtzite type structure. In addition, oxide and oxynitride phases were detected. The surface morphology of the substrates was also investigated, as it is the nature of the surface that will be of importance in determining the adhesion of applied films.

There is a strong inducement to develop new inorganic materials to substitute the current industrial pigments, which are known for their poor ultraviolet absorbent and low photoluminescence (PL) properties. The purpose of this paper is to invent a better rare-earth-based pigment material as a spectral modifier with good luminescence properties to enhance the spectral response for photovoltaic panel application.

Different phosphor samples made of nano-calcium carbonate (CaCO₃) with varied wt.% of the dopant Dysprosium doped calcium borophosphate (CBP/Dy) as (W0 – 0%, W1 – 3,85%, W2 – 7.41%, W3 –10.71% and W4 –13.79%) were prepared via the solid-state diffusion method at 600 °C for 6 h using a muffle furnace. The structural, morphological and luminescence properties of the CaCO₃:CBP/Dy powder samples were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and PL test.

The XRD, SEM and FTIR results verified the crystalline formation, morphological behaviour and vibration bonds of synthesized CBP/Dy-doped CaCO₃ powder samples. XRD pattern revealed that the synthesized powder samples exhibit crystalline structured materials, and SEM results showed irregular shape and porous-like structured morphologies. FTIR spectrum shows prominent bands at 712, 874 and 1,404 cm⁻¹, corresponding to asymmetric stretching vibrations of CO3²⁻ groups and out-of-plane bending. PL characterization of CBP/Dy-doped CaCO₃ (sample W) shows emission at 427 nm (λmax) under the excitation of 358 nm. The intensity of PL emission spectra drops due to the concentration quenching effect, while the maximum PL intensity is observed in the W3 phosphor powder system.

This phosphor powder is expected to find out the potential application such as a spectral modifier which is applied to match the energy of photons with solar cell bandgap to improve spectral absorption and lead to better efficiency.

The introduction of a nano-CaCO₃:CBP/Dy hybrid powder system with good luminescence properties to be used as spectral modifiers for solar cell application has been synthesized in the lab, which is a novel attempt.

After many very successful years as a researcher and manager at British Telecommunications Research Laboratories, Nihal Sinnadurai has moved over to consultancy with BPA (Technology & Management) Ltd.

This study aims to present a numerical study of atomic structure for aluminium nitride (AlN) when the crystal was assumed grown on different orientation of sapphire substrate. The change of the AlN atomic structure with sapphire orientation was associated to the interface between the AlN and the sapphire. The results from this study would provide a guideline in selecting suitable orientation of sapphire for obtaining desirable AlN crystals, in particular, for reducing threading dislocation density in the AlN/sapphire templates for developing UV LEDs.

The approach of atomic structure by visualization for electronic and structural analysis numerical method to develop shape of atomic geometry to evaluate which plane are more suitable for the AlGaN technology UV-LED based.

The calculation based on ratio on first and second layers can be done by introduction of lattice constant.

With plane’s color of cutting plane on bulky materials, all the shape looks the same.

By implementing this method, the authors can save time to find the most suitable plane on the growth structure.

All authors of this research paper have directly participated in the planning, execution or analysis of the study; all authors of this paper have read and approved the final version submitted; the contents of this manuscript have not been copyrighted or published previously; the contents of this manuscript are not now under consideration for publication elsewhere; the contents of this manuscript will not be copyrighted, submitted or published elsewhere, whereas acceptance by the journal is under consideration.

Nitrogen ion implantation on a Ti6Al4V alloy with 70KeV energy was carried out at different doses ranging from 5 × 10¹⁵ to 2.5 × 10¹⁷ions/cm². The implanted samples were subjected to open circuit potential/time measurement and cyclic polarization studies to evolve the optimum dose which can give good corrosion resistance in a simulated body fluid condition. The results show that there was an increase in corrosion resistance with increased doses up to 7 × 10¹⁶ions/cm², beyond which it started to decrease. The stability of the passive film at a higher potential was assessed by potentiotransient techniques after impressing a constant potential of 1.5V for three hours. The results of the investigation indicate that nitrogen ion implantation can be used as a viable method to improve the corrosion resistance of orthopaedic implant devices made of Ti6Al4V alloy. The nature of the stable passive film and its influence on corrosion resistance are discussed in this paper.