The effect of passivation layer, doping and spacer layer on electron-longitudinal optical phonon momentum relaxation time in Al0.3Ga0.7N/AlN/GaN heterostructures

Sonmez F., Ardali S., Atmaca G., Lisesivdin S. B. , Malin T., Mansurov V., ...More

MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING, vol.122, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 122
  • Publication Date: 2021
  • Doi Number: 10.1016/j.mssp.2020.105449
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Applied Science & Technology Source, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex
  • Keywords: Longitudinal optical phonon energy, Longitudinal optical phonon relaxation time, Hall mobility, AlGaN/GaN, Raman spectroscopy, Electron effective mass, HALL-EFFECT MEASUREMENTS, RAMAN-SCATTERING, EFFECTIVE-MASS, ALN SPACER, GAN, TRANSPORT, ACCUMULATION, SPECTROSCOPY, DISPERSION, ENERGY
  • Gazi University Affiliated: Yes


The Raman and classical Hall effect measurements have been used to determine the longitudinal optical phonon energy, effective mass, and optical phonon relaxation times in Al0.3Ga0.7N/AlN/GaN heterostructures grown by the Molecular Beam Epitaxy (MBE) technique. The classical Hall effect measurements were performed at temperatures between 1.8 and 262 K at a fixed magnetic field, while Raman measurements were performed at room temperature. The longitudinal optical (LO) phonon energy has been found at higher temperatures where Hall mobility data is rapidly decreasing. The effective mass is obtained by comparing the A(1)(LO) peak obtained from Raman measurements to theoretical calculations. The effect of passivation, spacer layer, and doping on the LO phonon relaxation times were determined. The LO phonon relaxation times, which are important for the device's performance, were found between 8.97 and 9.20 fs.