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This paper investigates the pattern or trajectory of implementing ISO 9000 standards versus TQM in Western Europe from a longitudinal perspective, using empirical data. The research is based on three large‐scale surveys conducted in 1992‐1993, 1996‐1997 and 2001‐2002 respectively, in 13 Western European countries. The results of the surveys show that European companies have put considerable effort into ISO 9000 certification. However, the results also reveal that, around 1996‐1997, European companies had also planned to implement TQM. However, the result of the planned “go beyond ISO to TQM” fell short of the anticipated extent, indicating that the adoption of TQM in Europe was slower than expected. Early in the twenty‐first century, European companies are still very keen on implementing TQM, indicating an obvious intention to shift from ISO 9000 to TQM. To ensure that the shift will occur this time however, the two approaches must be integrated properly. Although both ISO 9000 standards and the TQM/EFQM model have been recently updated or modified, how to best incorporate the two systems remains one of the major tasks of quality management in the future.

The purpose of this paper was to obtain by means of selective laser melting and then characterize biocomposites of medical-grade Ti6Al7Nb with hydroxyapatite (2 and 5 vol.%) and without hydroxyapatite, as reference.

Rectangular samples were manufactured with the same scanning strategy; the laser power was between 50 W and 200 W. Processed samples were analysed by means of optical microscopy, scanning electron microscopy and microhardness.

The results showed that despite the very short processing times, hydroxyapatite decomposed and interacted with the base Ti6Al7Nb material. The decomposition degree was found to depend on the applied laser power. From the porosity and bulk microstructure point of view, the most appropriate materials for the purposed medical applications were Ti6Al7Nb with hydroxyapatite processed with a laser power of 50 W.

The originality of the present work consists in the study of the behaviour and interaction of hydroxyapatite additive with the Ti6Al7Nb base powder under selective laser melting conditions, as depending on the applied laser power.

Lapping is a vital flattening process to improve the quality of processed semiconductor wafers such as single-crystal sapphire wafers. This study aims to optimise the lapping process of the fixed-abrasive lapping plate of sapphire wafers with good overall performance [i.e. high material removal rate (MRR), small surface roughness (Ra) of the wafers after lapping and small lapping plate wear ratio (η)].

The influence of process parameters such as lapping time, abrasive size, abrasive concentration, lapping pressure and lapping speed on MRR, Ra and η of lapping-processed sapphire wafers was studied, and the results were combined with experimental data to establish a regression model. The multi-evaluation index optimisation problem was transformed into a single-index optimisation problem via an entropy method and the grey relational analysis (GRA) to comprehensively evaluate the performance of each parameter.

The results revealed that lapping time, abrasive size, abrasive concentration, lapping pressure and lapping speed had different influence degrees on MRR, Ra and η. Among these parameters, lapping time, lapping speed and abrasive size had the most significant effects on MRR, Ra and η, and the established regression equations predicted the response values of MRR, Ra and η to be 99.56%, 99.51% and 93.88% and the relative errors between the predicted and actual measured values were <12%, respectively. With increased lapping time, MRR, Ra and η gradually decreased. With increased abrasive size, MRR increased nearly linearly, whereas Ra and η initially decreased but subsequently increased. With an increase in abrasive concentration, MRR, Ra and η initially increased but subsequently decreased. With increased lapping pressure, MRR and η increased nearly linearly and continuously, whereas Ra decreased nearly linearly and continuously. With increased lapping speed, Ra initially decreased sharply but subsequently increased gradually, whereas η initially increased sharply but subsequently decreased gradually; however, the change in MRR was not significant. Comparing the optimised results obtained via the analysis of influence law, the parameters optimised via the entropy method and GRA were used to obtain sapphire wafers lapping with an MRR of 4.26 µm/min, Ra of 0.141 µm and η of 25.08, and the lapping effect was significantly improved.

Therefore, GRA can provide new ideas for ultra-precision processing and process optimisation of semiconductor materials such as sapphire wafers.

The Fabry-Perot sapphire optical fiber sensor is an excellent choice for high-temperature sensing in civil and military fields, such as oil exploitation, engine and turbine. The purpose of this paper is to study the high-reflective film system withstanding high temperature in Fabry-Perot sapphire optical fiber high-temperature sensor. To improve the performance of the sensor and reduce the difficulty of signal acquisition, one of the key ways is to enhance the normalized light intensity of F-P sensor, which can be achieved by coating the high-reflective film system on the fiber end.

The high-reflective film system can be achieved by a multilayer film with alternating ZrO₂ and Al₂O₃ film layers whose refractive indexes are different. In addition, the optimum film alternating sequences and the influence of the number of film layers, incident angle and temperature should be obtained by numerical analysis.

With the increase of the number of film layers, the reflectivity rises gradually and the change trend is more and more gentle. A minimum of the spectral reflectivity will occur at a certain incident angle depending on the design of the periodic multilayer system. Temperature affects the reflectivity of high-reflective film system. The normalized light intensity of the F-P sensor coated with high-reflective film system enhances greatly which is helpful to the signal demodulation. The temperature response of the F-P sensor is mainly determined by the characteristics of the F-P cavity.

Higher reflectivity, lower cost and easy signal acquisition are the most important features of the introduced high-reflective film system for the Fabry-Perot sapphire optical fiber high-temperature sensor.

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.

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 aims of this paper is to study the effects of the V/III ratio of indium gallium nitride (InGaN) quantum wells (QWs) on the structural, optical and electrical properties of near-ultraviolet light-emitting diode (NUV-LED).

InGaN-based NUV-LED is successfully grown on the c-plane patterned sapphire substrate at atmospheric pressure using metal organic chemical vapor deposition.

The indium composition and thickness of InGaN QWs increased as the V/III ratio increased from 20871 to 11824, according to high-resolution X-ray diffraction. The V/III ratio was also found to have an important effect on the surface morphology of the InGaN QWs and thus the surface morphology of the subsequent layers. Apart from that, the electroluminescence measurement revealed that the V/III ratio had a major impact on the light output power (LOP) and the emission peak wavelength of the NUV-LED. The LOP increased by up to 53% at 100 mA, and the emission peak wavelength of the NUV-LED changed to a longer wavelength as the V/III ratio decreased from 20871 to 11824.

This study discovered a relation between the V/III ratio and the properties of QWs, which resulted in the LOP enhancement of the NUV-LED. High TMIn flow rates, which produced a low V/III ratio, contribute to the increased LOP of NUV-LED.

The purpose of this paper is to study the structural and optical characterization of Al_x In_y Ga_1−x−y N quaternary epilayers, which were grown on c‐plane (0001) sapphire substrates with AlN as buffer layers using plasma assisted molecular beam epitaxy technique with indium (In) mole fraction y ranging from 0.0 to 0.1 and constant aluminum (Al) mole fraction x=0.06.

High‐resolution X‐ray diffraction rocking curve (HRXRD‐RC), scanning electron microscopy (SEM), energy dispersive X‐ray spectrometry (EDX), and photoluminescence (PL) spectroscopy have been measured on quaternary Al_x In_y Ga_1−x−y N thin films at room temperature.

HRXRD‐RC measurements confirmed that the Al_x In_y Ga_1−x−y N alloys had wurtzite structure. SEM images, element composition analysis by EDX, provided the evidence to show the existence of defects inside the samples contaminated by silicon from previous growth leading to nonuniformity of the epilayers, which caused decreased in the quality of the samples. PL spectra show reducing of the integrated intensity and an increasing red shift with increasing in content with reference to the ternary sample Al_0.06Ga_0.94N. The existence of a large amount of nonradiative recombination centers are responsible for the reduced the luminescence and the red shift provided evidence to an increase in composition inside the Al_x In_y Ga_1−x−y N quaternary alloys. Photoluminescence is used to determine the behavior of the near band edge emission represent the energy band gap of the quaternary films. The energy band gap decreases with increasing In composition from 0.01 to 0.1 mole fraction. This trend is expected since the incorporation of in reduced the energy band gap of ternary Al_0.06Ga_0.94N (3.529 eV). We have also investigated the bowing parameter of the variation of energy band gaps and found it to be very sensitive on in composition. A value of b=10.95 have been obtain for our quaternary Al_x In_y Ga_1−x−y N alloys.

This study on quaternary samples described in this paper, clearly indicates that the present of defects due to impurity contaminations has a dominant role in determining the structural and optical properties of Al_x In_y Ga_1−x−y N quaternary alloys.

The purpose of this paper is to report the structural properties of Al_xGa_1−xN (0≤x≤1) grown on sapphire substrate by means of X‐ray diffraction (XRD) technique. The main purpose of this work was to investigate the effects of Al(x) composition to the structural and microstructural properties of Al_xGa_1−xN ternary alloy such as the crystalline quality, crystalline structure and lattice constant c.

Al_xGa_1−xN thin films with wurtzite structure in the composition range of 0≤x≤1 are used in this study. The compositions of the samples are calculated using Vegard's law and verified by energy dispersive X‐ray analysis. The samples are then characterized by means of XRD rocking curve (RC) and phase analysis.

Investigation revealed that the full width half maximum (FWHM) of RC increase with the increase x value. This indicates that the crystalline quality of the samples deteriorate with the increase of Al compositions. The best fit of the non‐linear interpolation of the FWHM of the (002) diffraction RC data suggested that a maximum disorder should be expected in this mixed crystals system when the composition x≈45 percent.

This paper provides valuable information on the effect of Al compositions to the structural characteristics of Al_xGa_1−xN alloy system. The availability of information about maximum disorder of Al composition in Al_xGa_1−xN (0≤x≤1) alloy system provides useful reference in device fabrications where researchers are able to choose correct alloy composition in order to fabricate good quality devices.