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The purpose of this paper is to: analyze the changing properties of epitaxial layers, manufactured in the considered reactor, with the changing parameters of the growth taking into account native convection; and development of the most common analytical approach to describe the technological process.

In this paper a vertical reactor for gas phase epitaxy is considered that consists of an external casing, a keeper of substrate with a substrate and a spiral around the casing in area of the growth zone to generate induction heating in order to activate the chemical reactions in the decay of reagents and the growth of the epitaxial layer by using the reagents. The authors introduce an analytical approach to analyze nonlinear mass and heat transport with account variation in space and time parameters.

The authors find conditions to improve properties of epitaxial layers.

Growth regimes at atmospheric and low pressure have been compared and analyzed for their influence of the native convection on the growth of the epitaxial layers. Accounting for the calculated results, recommendations have been formulated to improve the properties of the epitaxial layers.

Describes the key attributes of MEMS technology and existing and future business opportunities. Discusses the various stages in the fabrication of MEMS devices and offers guidance regarding the selection of processing methods for deposition, lithography and etching. Also describes the MEMS‐Exchange program and associated network of fabrication centres.

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

This paper seeks to describe automated lamp manufacturing.

The paper provides information on the automated manufacture of incandescent, fluorescent and light‐emitting diodes (LEDs).

The paper finds that the automated manufacture of conventional lamp types is similar, but LEDs require totally different techniques developed from the semiconductor industry.

The paper should be of value in terms of understanding the basics of automated lamp manufacturing, especially with LEDs, as these will be highly important general lighting products to save energy and provide innovation in lighting design in the near future.

The paper aims to provide a technical review of the application of quantum dot (QD) technology to sensors.

Following a brief introduction to QD technology, this paper considers recent research on QD‐based physical, chemical and gas sensors.

This shows that QDs are being exploited in a range of experimental sensors for detecting physical variables, notably radiant/electromagnetic quantities and temperature; chemical compounds, such as metals and many species of clinical interest; and a variety of gases and vapours. Prospects also exist to develop improved sources and detectors for use in optical gas sensors.

The paper does not consider biomedical uses of QDs such as cellular imaging, bioassays and biosensors.

This provides a detailed insight into recent research on physical, chemical and gas sensors based on QD technology.

Optoelectronic components such as lasers and avalanche photodiodes have already revolutionised long distance transmission, and yet the technology is still in its infancy. Future generations of optoelectronic components will see the increasing integration of electronic, optoelectronic and optical functions on single chips, bringing about dramatic improvements in performance and the lower costs that will be required for widescale introduction of broadband networks and services.

This paper aims to report on the use of radio frequency nitrogen plasma‐assisted molecular beam epitaxy (RF‐MBE) to grow high‐quality n‐type In_0.47Ga0.53N/GaN on Si(111) substrate using AlN as a buffer layer.

Structural analyses of the InGaN films were performed by using X‐ray diffraction, atomic force microscopy, and Hall measurement. Metal‐semiconductor‐metal (MSM) photodiode was fabricated on the In_0.47Ga0.53N/Si(111) films. Electrical analysis of the MSM photodiodes was carried out by using current‐voltage (I‐V) measurements. Ideality factors and Schottky barrier heights for Ni/In_0.47Ga0.53N, was deduced to be 1.01 and 0.60 eV, respectively.

The In_0.47Ga0.53N MSM photodiode shows a sharp cut‐off wavelength at 840 nm. A maximum responsivity of 0.28 A/W was achieved at 839 nm. The detector shows a little decrease in responsivity from 840 to 200 nm. The responsivity of the MSM drops by nearly two orders of magnitude across the cut‐off wavelength.

Focuses on III‐nitride semiconductors, which are of interest for applications in high temperature/power electronic devices.

This paper aims to focus on the basic principle of WO₃ gas sensors to achieve high gas-sensing performance with good stability and repeatability. Metal oxide-based gas sensors are widely used for monitoring toxic gas leakages in the environment, industries and households. For better livelihood and a healthy environment, it is extremely helpful to have sensors with higher accuracy and improved sensing features.

In the present review, the authors focus on recent synthesis methods of WO₃-based gas sensors to enhance sensing features towards toxic gases.

This work has proved that the synthesis method led to provide different morphologies of nanostructured WO₃-based material in turn to improve gas sensing performance along with its sensing mechanism.

In this work, the authors reviewed challenges and possibilities associated with the nanostructured WO₃-based gas sensors to trace toxic gases such as ammonia, H₂S and NO₂ for future research.

The purpose of this paper is to examine the growth and characterization of the two different compound semiconductors, namely, n-zinc oxide (ZnO) and p-gallium antimonide (GaSb). In this paper, fabrication and characterization of n-ZnO/p-GaSb heterojunction diode is analyzed.

Thermo vertical direction solidification (TVDS) method was used to synthesize undoped GaSb ingot from high purity Ga (5N) and Sb (4N) host materials. Thermal evaporation technique is used to prepare a film of GaSb on glass substrate from the pre-synthesized bulk material by TVDS method. Undoped ZnO film was grown on GaSb film by sol–gel method by using chemical wet and dry (CWD) technique to fabricate n-ZnO/p-GaSb heterojunction diode.

The formation of crystalline structure and surface morphological analysis of both the GaSb bulk and film have been carried out by x-ray diffraction (XRD) analysis and scanning electron microscopy analysis. From the XRD studies, the structural characterization and phase identification of ZnO/GaSb interface. The current–voltage characteristic of the n-ZnO/p-GaSb heterostructure is found to be rectifying in nature.

GaSb film growth on any substrate by thermal evaporation method taking a small piece of the sample from the pre-synthesized GaSb bulk ingot has not been reported yet. Semiconductor device with heterojunction diode by using two different semiconductors such as ZnO/GaSb was used by this group for the first time.