Atomic Force Microscopy Studies of Homoepitaxial GaN Layers Grown on GaN Template by Laser MBE.
- Resource Type
- Article
- Authors
- Choudhary, B. S.; Singh, A.; Tanwar, S.; Tyagi, P. K.; Kumar, M. Senthil; Kushvaha, S. S.
- Source
- AIP Conference Proceedings. 2016, Vol. 1724 Issue 1, p1-5. 5p. 1 Color Photograph, 1 Diagram, 1 Chart, 2 Graphs.
- Subject
- *ATOMIC force microscopy
*HOMOEPITAXY
*GALLIUM nitride
*MOLECULAR beam epitaxy
*SURFACE morphology
- Language
- ISSN
- 0094-243X
We have grown homoepitaxial GaN films on metal organic chemical vapor deposition (MOCVD) grown 3.5 µm thick GaN on sapphire (0001) substrate (GaN template) using an ultra-high vacuum (UHV) laser assisted molecular beam epitaxy (LMBE) system. The GaN films were grown by laser ablating a polycrystalline solid GaN target in the presence of active r.f. nitrogen plasma. The influence of laser repetition rates (10-30 Hz) on the surface morphology of homoepitaxial GaN layers have been studied using atomic force microscopy. It was found that GaN layer grown at 10 Hz shows a smooth surface with uniform grain size compared to the rough surface with irregular shape grains obtained at 30 Hz. The variation of surface roughness of the homoepitaxial GaN layer with and without wet chemical etching has been also studied and it was observed that the roughness of the film decreased after wet etching due to the curved structure/rough surface. [ABSTRACT FROM AUTHOR]