A Different Approach to Absorption Coefficient and Thickness

Öz

In this study structural and morphological properties of InGaN/GaN/Al2O3 structure, grown by Metal Organic Chemical Vapor Deposition (MOCVD) technique, is investigated. Crystal size of GaN in the structure is determined by using X-Ray Diffraction (XRD) techique. By the help of Raman spectra calibration coefficient is gained. This calibration coefficient and Termoelectric figure (ZT) of GaN is used to estimate number of stacks of GaN in the structure. Number of stacks (N) is a structural property and by using it an optical property, absorption coefficient, is determined. Using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) images total thickness of the sample is determined accurately and they are compared with each other. The sample used in this study is only for an example. The methods used in this study can be applied to different structures if right coefficients can be found. The importance of this study is that it plays a key role for determining structural, optical and morphological features of different samples.

Anahtar Kelimeler

• InGaN
• XRD
• SEM
• AFM
• Raman

Proje Numarası

2016K121220

Soğurma Katsayısı ve Kalınlığa Farklı Bir Yaklaşım

Öz

Bu çalışmada, metal organic kimyasal buhar biriktirme(MOCVD) yöntemiyle büyütülen InGaN/GaN/Al2O3 yapısının yapısal ve morfolojik özellikleri incelendi. GaN’ın kristal boyutu X-ışını kırınımı (XRD) tekniği ile belirlendi. Raman spektrumu kullanılarak kalibrasyon katsayısı belirlendi. Kalibrasyon katsayısı ve termoelektrik figure (ZT) yapıdaki GaN’a ait yığın sayısını tahmin etmek için kullanıldı. Yığın sayısı (N) yapısal bir özelliktir ve onu kullanarak optik bir özellik olan soğurma katsayısı belirlendi. Atomik kuvvet mikroskobisi (AFM) ve tarama elektron mikroskobisi (SEM) kullanılarak numunenin toplam kalınlığı tam olarak belirlendi ve birbiri ile kıyaslandı. Bu çalışmada kullanılan numune sadece bir örnek teşkil eder. Eğer doğru katsayılar bulunabilirse farklı yapılara da uyarlanabilir. Bu çalışmanın önemi, farklı numunelerin optik, yapısal ve morfolojik özelliklerini belirleyebilmek için anahtar rolü oynamasıdır.

Anahtar Kelimeler

• InGaN
• GaN
• XRD
• SEM
• AFM
• Raman

Destekleyen Kurum

Presidency Strategy and Budget Directorate

Proje Numarası

2016K121220

Teşekkür

Makalemizi derginize gönderme fırsatı sunduğunuz için teşekkür ederiz.

Kaynakça

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