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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.

The purpose of this paper is to synthesize porous zinc oxide (ZnO) by means of strain etching/wet chemical etching method with the use of 0.5% of nitric acid (HNO₃) etchant. The structural and surface morphological properties of the samples are accessed by using X‐ray diffraction (XRD) and scanning electron microscopy (SEM) characterization techniques.

ZnO samples used in this work were deposited on the p‐Si (111) substrates by using radio frequency (RF) sputtering technique. Wet chemical etching processes with the use of 0.5% HNO₃ etchant was applied on these samples in order to obtain porous structure. The porous ZnO samples are characterized by means of XRD and SEM to access their structural and surface morphological properties.

The XRD and SEM cross‐sectional measurements revealed that the thickness of the etched ZnO thin films is proportional to the etching time. SEM micrographs show that the surface morphology of ZnO changes over etching time. On the other hand, XRD results indicate that the crystallite sizes of the ZnO(002) decreases when the etching time increases.

The paper shows how porous ZnO thin films have been successfully synthesized by using simple wet chemical etching. SEM images reveal that this method is reliable when producing porous structure ZnO surfaces.