Correlation of structural and optical properties of AlGaN films grown on SiN-treated sapphire by MOVPE
Name:
pagination_MSB_114866-final.pdf
Size:
1.979Mb
Format:
PDF
Description:
Accepted manuscript
Type
ArticleAuthors
Bouzidi, MohamedAlshammari, Abdullah S.
Soltani, Sonia
Halidou, Ibrahim
Chine, Zied
Raza Khan, Ziaul
Chaaben, Noureddine
Shakfa, Mohammad Khaled
KAUST Department
King Abdullah University of Science & Technology (KAUST), Physical Science and Engineering Division, Thuwal 23955-6900, Saudi ArabiaDate
2020-10-22Online Publication Date
2020-10-22Print Publication Date
2021-01Embargo End Date
2022-10-22Submitted Date
2020-04-13Permanent link to this record
http://hdl.handle.net/10754/665732
Metadata
Show full item recordAbstract
We investigated the structural and optical properties of AlGaN films grown on SiN-treated sapphire substrates, without and with GaN-template, by atmospheric pressure metal organic vapor phase epitaxy. The samples were characterized using high-resolution X-ray diffraction (HR-XRD), time-resolved photoluminescence (TR-PL), and photoreflectance (PR) spectroscopies. Furthermore, the carrier mobility was determined from Hall-effect measurements. When the AlGaN (GaN-template) layer thickness increases up to 0.6 µm (1.3 µm), an increase in the PL decay times is observed and correlated with the transition from 3D to 2D growth mode resulting in a decrease in the dislocations density as obtained from the HR-XRD measurements. Beyond the aforementioned layer thicknesses, we observed a deterioration in the PL transient corresponds to an increase in the density of VAl-related complexes during the relaxation process, which act as non-radiative recombination centers. Our observations strongly suggest that this type of defects influences the carrier transport and carrier recombination process in the AlGaN layers. Furthermore, our results reveal a phenomenological linear relationship between the internal electric field, obtained from the PR measurements, and the dislocations density. This finding predicts an increase in the GaN internal electric field by about 147 KV/cm when the Al content is increased to 7% in the AlGaN layers. We attribute this increase to a rise in the polarization-induced electric field due to Al incorporation in the AlGaN layer. Based on the obtained correlation between the internal electric field and the dislocation density, we propose an experimental approach that can be utilized to determine the internal electric field, at zero dislocation density, which is very important for designing high-efficient electronic and optoelectronic devices.Citation
Bouzidi, M., Alshammari, A. S., Soltani, S., Halidou, I., Chine, Z., Raza Khan, Z., … Shakfa, M. K. (2021). Correlation of structural and optical properties of AlGaN films grown on SiN-treated sapphire by MOVPE. Materials Science and Engineering: B, 263, 114866. doi:10.1016/j.mseb.2020.114866Sponsors
This research has been funded by Scientific Research Deanship at the University of Ha'il (Saudi Arabia), through project number RG-191242. The authors are very grateful to Prof. Dr. Martin Koch of the physics department of the Philipp University of Marburg for giving the opportunity to perform time-resolved photoluminescence measurements in his laboratory.Publisher
Elsevier BVAdditional Links
https://linkinghub.elsevier.com/retrieve/pii/S0921510720303731ae974a485f413a2113503eed53cd6c53
10.1016/j.mseb.2020.114866