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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.

To design and optimize the traditional aluminum gallium nitride/gallium nitride high electron mobility transistor (HEMT) device in achieving improved performance and current handling capability using the Synopsys’ Sentaurus TCAD tool.

Varying material and physical considerations, specifically investigating the effects of graded barriers, spacer interlayer, material selection for the channel, as well as study of the effects in the physical dimensions of the HEMT, have been extensively carried out.

Critical figure-of-merits, specifically the DC characteristics, 2DEG concentrations and mobility of the heterostructure device, have been evaluated. Significant observations include enhancement of maximum current density by 63 per cent, whereas the electron concentration was found to propagate by 1,020 cm⁻³ in the channel.

This work aims to provide tactical optimization to traditional heterostructure field effect transistors, rendering its application as power amplifiers, Monolithic Microwave Integrated Circuit (MMICs) and Radar, which requires low noise performance and very high radio frequency design operations.

Analysis in covering the breadth and complexity of heterostructure devices has been carefully executed through extensive TCAD modeling, and the end structure obtained has been optimized to provide best performance.

A silver‐palladium thick film conductor for aluminum nitride (AlN) substrate has been developed. This conductor film on AlN ceramics had low sheet resistivity, high adhesion strength and good wettability with Pb‐Sn solder. The frit powder of lead borosilicate glass was used as inorganic binders to enhance the adhesion between the conductor and ceramics. After sintering the conductor film connected with the AlN substrate through frit bonding, no transition phases but a multilayer structure is present in the interface. The softening point of the glass was important to the adhesion strength of conductor film. In order to achieve good adhesion, it is necessary that the glass has a proper softening point (about 500‐650°C).

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 report the influence of sputtering plasma deposition time on the structural and mechanical properties of the a-axis oriented aluminium nitride (AlN) thin films.

The AlN films were prepared using RF magnetron sputtering plasma on a silicon substrate without any external heating with various deposition times. The films were characterized using X-ray diffraction (XRD), field-emission scanning electron microscope (FESEM), atomic force microscope (AFM) and nanoindentation techniques.

The XRD results show that the AlN thin films are highly oriented along the (100) AlN plane at various deposition times indicating the a-axis preferred orientation. All the AlN thin films exhibit hexagonal AlN with a wurtzite structure. The hardness and Young’s modulus of AlN thin films with various deposition times were measured using a nanoindenter. The measured hardness of the AlN films on Si was in the range of 14.1 to 14.7 GPa. The surface roughness and the grain size measured using the AFM revealed that both are dependent on the deposition times.

The novelty of this work lies with a comparison of hardness and Young’s modulus result obtained at different sputtering deposition temperature. This study also provides the relation of AlN thin films’ crystallinity with the hardness of the deposited films.

The aim of this paper is to present non-destructive and destructive methods of failure analysis of epoxy moulded IC packages on the example of power MOSFETs in SOT-227 package.

A power MOSFET in SOT-227 package was examined twice using X-ray inspection, at first as the whole component to check if it is damaged and then after removing the upper part of package by mechanical grinding. The purpose of the second X-ray inspection was to prepare images for estimation of the total number and approximate location of voids in soft solder layers. Finally, power MOSFETs were subjected to decapsulation process using a concentrated sulphuric acid to verify existence of damage areas noticed during X-ray analysis and to observe other possible failures such as cracks in aluminium metallization or wires deformation.

X-ray analysis was revealed to be adequate technique to detect damage (e.g. meltings) in power MOSFETs in SOT-227 package, but only when tested components were analysed in the side view. This type of analysis combined with a graphic software is also suitable for voids estimation in soft solder layers. Moreover, it was found that a single acid (concentrated sulphuric acid) at elevated temperature can be successfully used for decapsulation of power MOSFETs in SOT-227 package without damage of aluminium metallization and aluminium wires. Such decapsulation process enables analysis of defects in wire, die and package materials.

Further investigations are required to examine if the presented methods of failures analysis can be used for other types of components (e.g. high power resistors) in similar packages.

The described methods of failure analysis can find application in electronic industry to select components which are free of damage and in effect which allow to produce high reliable devices. Apart from it, the presented method is applicable to evaluate reasons of improper work of tested electronic devices and to identify faked components.

This paper contains valuable information for research and technical staff involved in the assessment of electronic devices who needs practical methods of failure analysis of epoxy moulded IC packages.

The purpose of this study is to investigate the influence of AlN nucleation thickness in reducing the threading dislocations density in AlN layer grown on sapphire substrate.

In this work, the effect of the nucleation thickness at 5 nm, 10 nm and 20 nm on reducing the dislocation density in the overgrown AlN layer by metal organic chemical vapor deposition was discussed. The AlN layer without the nucleation layer was also included in this study for comparison.

By inserting the 10 nm thick nucleation layer, the density of the dislocation in the AlN layer can be as low as 9.0 × 10⁸ cm⁻². The surface of the AlN layer with that nucleation layer was smoother than its counterparts.

This manuscript discussed the influence of nucleation thickness and its possible mechanism in reducing dislocations density in the AlN layer on sapphire. The authors believe that the finding will be of interest to the readers of this journal, in particular those who are working on the area of AlN.

The purpose of this paper is to present the characteristics of novel silicon Schottky barrier (SB) photodiodes (PDs) with aluminium nitride (AlN) (100 nm) nucleation layer.

Comparison was made with conventional silicon SB PDs.

It was found that smaller dark current could be achieved with AlN nucleation layer. It was also found that effective SB height increased from 0.65 to 0.71 eV with the insertion of the AlN layer. The dark leakage current for the Schottky PDs with the AlN layer was shown to be about two orders of magnitude smaller than that for the conventional silicon SB PDs.

It is possible that the detrimental effect of interface states situated near the metal semiconductor interface was less pronounced for the sample owing to the insertion of the AlN nucleation layer.

There is believed to be no other report on silicon SB PDs capped with an AlN layer in the literature. This paper describes the fabricated silicon SB PDs and reports on the electrical characteristics of the devices with an AlN nucleation layer grown at low temperature.

The purpose of this paper is to present the influence of gate dielectric etching on obtained MISFET (metal insulator semiconductor field effect transistor) structures. Because of its properties, aluminum nitride (AlN) layers can be successfully used in a large area of applications. In addition, AIN has a wide bandgap (6.2eV) and high thermal conductivity (3.2 W/cm * K). Its melting temperature is greater than 2,000°C. The relative permittivity is about 9. All these features (especially high power, high temperature and high-frequency) make AlN a useful material in the fields of electronic, optical and acoustic applications.

To fabricate n-channel transistors, silicon technology was used. The 50-nm thick AlN films were deposited using the magnetron sputtering. After preparation of SiO₂/AlN stack as the gate dielectric, the optimization processes of dry etching in plasma environment by Taguchi method were realized. In the next step, three methods of AlN etching were selected and used to MISFET device fabrication. Atomic force microscopy and scanning electron microscopy allowed to surfacing of the state observation after etching process. The current–voltage (I–V) output and transfer characteristics of structures with modified etch technology were measured. Keithley SMU 236/237/238 measurement set was used.

In this research work, a method of AlN etching in a field effect transistor technology was developed and improved. Current−voltage characteristics of obtained MISFET structures were measured and compared. Influence of etching procedure on transistors properties was examined.

The obtained results allow improving the MISFET technology based on AlN film as a gate dielectric. The complete research work will allow using the developed technologies to implement in highly sensitive ion-sensitive field effect transistor (ISFET) structures in the future. The improvement of the etching element in the technology strongly influences the detection capabilities and operating range of the transistor.

This study aims to investigate the effect of temperature applied at the initial deposition of Aluminium Nitride (AlN) thin-film on a silicon substrate by high-power impulse magnetron sputtering (HiPIMS) technique.

HiPIMS system was used to deposit AlN thin film at a low output power of 200 W. The ramping temperature was introduced to substrate from room temperature to maximum 100°Cat the initial deposition of thin-film, and the result was compared to thin-film sputtered with no additional heat. For the heat assistance AlN deposition, the substrate was let to cool down to room temperature for the remaining deposition time. The thin-films were characterized by X-ray diffraction (XRD) and atomic force microscope (AFM) while the MIS Schottky diode characteristic investigated through current-voltage response by a two-point probe method.

The XRD pattern shows significant improvement of the strong peak of the c-axis (002) preferred orientation of the AlN thin-film. The peak was observed narrowed with temperature assisted where FWHM calculated at 0.35° compared to FWHM of AlN thin film deposited at room temperature at around 0.59°. The degree of crystallinity of bulk thin film was improved by 28% with temperature assisted. The AFM images show significant improvement as low surface roughness achieved at around 0.7 nm for temperature assisted sample compares to 3 nm with no heat applied.

The small amount of heat introduced to the substrate has significantly improved the growth of the c-axis AlN thin film, and this method is favorable in the deposition of the high-quality thin film at the low-temperature process.