Crystal Size and Stress Account in Reciprocal Space Map

İlknur KARS DURUKAN; Mustafa Kemal ÖZTÜRK; Süleyman ÖZÇELİK; Ekmel ÖZBAY

doi:10.2339/politeknik.417752

Crystal Size and Stress Account in Reciprocal Space Map

Authors : İlknur KARS DURUKAN, Mustafa Kemal ÖZTÜRK, Süleyman ÖZÇELİK, Ekmel ÖZBAY

Pages : 1-9

Doi:10.2339/politeknik.417752

View : 23 | Download : 10

Publication Date : 2019-03-01

Article Type : Research Paper

Abstract :In this study, five periodic InGaN / GaN LED insert ignore into journalissuearticles values(light emitting diode); structures grown by the Metal Organic Vapor Deposition insert ignore into journalissuearticles values(MOCVD); at different active layer growth temperatures were studied. These structures were grown as InGaN / GaN multiple quantum wells insert ignore into journalissuearticles values(MQW); between c-oriented sapphire substrate and n-GaN and p-AlGaN + GaN contacts. These constructions were characterized by the high-resolution X-ray diffraction insert ignore into journalissuearticles values(HR-XRD); system. HRXRD patterns obtained by X-ray diffraction and Reciprocal space maps were performed from the same data. One of the most effective ways of studying the crystal lattice is reciprocal space mapping with HR-XRD technique. This technique does not damage the sample. Information can be obtained from the internal system of the sample or from the intermediate layer including substrate. Using the FWHM insert ignore into journalissuearticles values(β hkl ); values and the elastic coefficients of the structures obtained for each of the three samples separately with the inverse mesh technique, D insert ignore into journalissuearticles values(nm); particle size, σ insert ignore into journalissuearticles values(GPa); uniform stress, ε strain, u insert ignore into journalissuearticles values(kJm -3 ); anisotropic energy density parameters were calculated. These calculations were done in a Scherrer method and Uniform Deformation Model insert ignore into journalissuearticles values(UDM); which is the Williamson Hall method, modified uniform Williamson stresses model insert ignore into journalissuearticles values(USDM); and Uniform Deformation Energy Density Model insert ignore into journalissuearticles values(UDEDM);. The results show that the stretching in the crystal size is very little. Line expansion in HR-XRD is due to small crystal size and lattice strain. UDEDM, one of the W-H methods, has emerged as the most suitable model for stretching..
Keywords : Strain, particle size, Williamson Hall, reciprocal space mapping

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