Mosaic Defect and AFM Study on GaN/AlInN/AlN/Sapphire HEMT Structures

Year 2022, Volume: 25 Issue: 4, 1613 - 1619, 16.12.2022

Ahmet Kursat Bılgılı Erkan Hekin Mustafa Ozturk Süleyman Özçelik Ekmel Özbay

https://doi.org/10.2339/politeknik.787700

Abstract

In this study, three samples of GaN/AlInN/AlN/Al2O3 high electron mobility (HEMT) structures are investigated with high resolution X-ray diffraction (HR-XRD) technique. Peak positions and peak broadenings are used in calculations, gained from rocking curves. Structural quality is determined from symmetric and asymmetric peak planes. Mosaic defects such as treadening dilocations (TDs), tilt and twist angles, lateral and vertical crystallite lengths are determined by using Williamson Hall (WH) method. In addition to these, surface morphology is also investigated by atomic force microscopy (AFM). It is noticed that crystal quality of epitaxial layers decrease in the order of samples C, B and A. Al compositions for samples A, B and C are found as %87.4, %86.6 and %86.4, respectively by using Vegard’s law.

Keywords

GaN, AlInN, AlN, sapphire, HEMT

Supporting Institution

Presidency Strategy and Budget Directorate

Project Number

2016K121220

Thanks

This work was supported by Presidency Strategy and Budget Directorate (Grant Number: 2016K121220).

GaN/AlInN/AlN/Safir HEMT Yapılar için Mozaik Kusur ve AFM Çalışması

Abstract

Bu çalışmada GaN/AlInN/AlN/Al2O3 yüksek elektron mobiliteli transistör (HEMT) yapıları üç numune olacak şekilde, yüksek çözünürlüklü X-ışınları kırınımı (HR-XRD) tekniği ile incelendi. Hesaplamalarda roking eğrilerinden elde edilen pik pozisyonları ve pik genişlemeleri kullanıldı. Yapısal kalite simetrik ve asimetrik pik düzlemlerinden faydalanılarak belirlendi. Tedirgin edici dislokasyonlar (TDs), eğim ve burkulma açıları, yanal ve düşey kristal uzunlukları gibi mozaik kusurlar Wiiliamson Hall (WH) metodu kullanılarak saptandı. Bunlara ilave olarak, yüzey morfolojisi atomik kuvvet mikroskopisi (AFM) yöntemiyle belirlendi. Epitaksiyel tabakaların kristal kalitesinin örnek C, B ve A sırasına göre düştüğü farkedildi. Örnekler A, B ve C için Al kompozisyonlarının sırasıyla %87.4, %86.6 ve %86.4 olduğu Vegard yasası kullanılarak belirlendi.

Keywords

GaN, AlInN, AlN, HEMT, safir

Project Number

2016K121220

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