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Background: Energy is a major concern in every aspect of our life. Solar energy is a renewable environmentally friendly source of energy. Therefore, solar cells are vastly studied with different technology and different material. Objective: The main objective here is to analyze InGaN material for solar cell applications with less complicated structures of MQW solar cells on revising solar cell with the recombination structure, I-V characteristics, and its efficiency. Methods: The device is simulated using SILVACO ATLAS, where the well and the barrier layers are inserted in the depletion region employing material combination of InGaN / GaN, which increases the solar cell performance parameter. This work focuses on the photogeneration rate, recombination in the active region as well as its current-voltage relation from the simulation. Results: With the increase in the number of QW periods in the active region of the device, the photovoltaic parameters especially conversion efficiency, increases significantly. Under space AM0 solar illumination, the cell efficiency increases up to 8.2 % for 20 MQWs with 20% Indium content for the InGaN/GaN structure. It enhances the External Quantum Efficiency (EQE) upto 36% at nearly 380nm wavelength range near the UV region. Conclusion: The modelled structure is efficiently simulated using TCAD SILVACO ATLAS, and the material Indium Gallium Nitride semiconductor shows an excellent solar cell performance with high solar radiation. It is also observed that with an increase in the number of well periods the solar cell performance increases, which demonstrates the feasibility of Indium Gallium Nitride solar cell with an additional MQW period as a power source.

Scanning probe microscopy (SPM) techniques have been developed and deployed to delineate the internal characteristics of electronic and photonic devices such as doping profiles, electric potential profile, electric field profile, and charge carrier profile, as they play a crucial role in the function and performance of biased and unbiased devices. Two of the most promising techniques, scanning spreading resistance microscopy (SSRM) and scanning capacitance microscopy (SCM), are now commercially available for two-dimensional (2-D) dopant profiling by the microelectronic and optoelectronic industries, but the techniques delineate only devices at equilibrium. Therefore, to directly observe the internal behavior of operating quantum optoelectronic devices, a new SPM technique, scanning voltage microscopy (SVM), has been developed.

The objective of this work is to study the optical and electrical properties of tantalum nitride and tantalum barrier thin films used against copper diffusion in Si in integrated circuits using spectroscopic ellipsometry in the VUV and UV–visible range. Single layers of tantalum nitride and bilayer films of Ta/TaN were produced by reactive magnetron sputtering on Si(100) substrates covered with a native oxide layer. Ellipsometric measurements were performed in the energy range from 0.73–8.7 eV and the dielectric functions were simulated using Drude–Lorentz model and effective medium approximation (EMA) in order to obtain information regarding film thickness, film composition, free carrier plasma energy, mean relaxation time and electrical resistivity. The film thickness clearly affects the electrical resistivity and the electron mean free path. It was observed that for films of Ta on TaN even after maintaining the deposition condition suitable for the β-phase of Ta, it turned out to be a mixture of α- and β-phases with higher contribution of the α-phase. It is shown that even a very small intermixture of two different phases of Ta can be determined accurately using ellipsometry. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Operative notes in surgical practice are a vital source of information and communication between healthcare professionals as well as being a legal document. Errors and omissions can have serious effects on patient care and lead to confusion. We audited our compliance within trauma and orthopaedics at a busy district general hospital in South East England with the standard set by the Royal College of Surgeons (England) before and after the introduction of an operation note template. We achieved significant improvements in compliance across almost all of the standard's domains and recommend widespread implementation of similar templates nationally.