| Title: |
Revealing threading dislocations in epitaxial GaN: a comparative study of electron channeling contrast imaging, KOH etch, and TEM characterization |
| Authors: |
Frascaroli, Jacopo; Serafini, Andrea; Vento, Fabiana; Somaini, Francesco; Piluso, Nicolò; Severino, Andrea; Calabretta, Cristiano; Mica, Isabella; Codegoni, Davide |
| Source: |
Semiconductor Science and Technology ; volume 41, issue 2, page 025009 ; ISSN 0268-1242 1361-6641 |
| Publisher Information: |
IOP Publishing |
| Publication Year: |
2026 |
| Description: |
In the development of compound semiconductors, gallium nitride (GaN) has garnered significant attention due to its excellent properties. However, the quality of the starting material plays a crucial role in device performance. An in-depth analysis is needed to identify, understand, and control typical material defects such as dislocations. The dislocations commonly found in GaN can be classified into Threading Screw Dislocations (TSDs), threading edge dislocations, and threading mixed dislocations. This study presents a comparison of three distinct techniques for characterizing these defects in GaN heteroepitaxial layers on silicon substrate, with each method offering unique strengths and limitations. Specifically, electron channeling contrast imaging in scanning electron microscopy was used for large-area non-destructive inspection of surface dislocations, providing a fast estimation of the dislocation density. Etching in molten potassium hydroxide (KOH), which is a destructive technique, revealed dislocations as etch pits corresponding to different GaN crystal faces. Finally, transmission electron microscopy characterization was applied in combination with both techniques to provide a detailed analysis of the dislocations, distinguishing between types of dislocations, while energy-dispersive x-ray spectroscopy allowed to identify etched layers and planes. Comparing the capabilities of these techniques, this study aims to enhance the understanding of dislocation detection and characterization in GaN, facilitating improved material design for radiofrequency and power electronic devices. |
| Document Type: |
article in journal/newspaper |
| Language: |
unknown |
| DOI: |
10.1088/1361-6641/ae3edf |
| DOI: |
10.1088/1361-6641/ae3edf/pdf |
| Availability: |
https://doi.org/10.1088/1361-6641/ae3edf; https://iopscience.iop.org/article/10.1088/1361-6641/ae3edf; https://iopscience.iop.org/article/10.1088/1361-6641/ae3edf/pdf |
| Rights: |
https://publishingsupport.iopscience.iop.org/iop-standard/v1 ; https://iopscience.iop.org/info/page/text-and-data-mining ; https://publishingsupport.iopscience.iop.org/questions/alternative-author-rights-policies/ ; https://publishingsupport.iopscience.iop.org/questions/alternative-author-rights-policies/ |
| Accession Number: |
edsbas.4472DC68 |
| Database: |
BASE |