Gunasekar, Nareshalazmi, anwar2024-11-252024https://hdl.handle.net/20.500.14154/73745This study investigates the impact of different growth methods and doping with iron (Fe) and tin (Sn) on the structural properties of bulk β-Ga2O3 by means of Raman spectroscopy. The β-Ga2O3 samples were synthesized using various methods: vertical Bridgman (VB), edge-defined film-fed growth (EFG), floating zone (FZ), halide vapor phase epitaxy (HVPE), and molecular beam epitaxy (MBE). Raman spectroscopy analysis of undoped β-Ga2O3 samples identified twelve Raman peaks corresponding to active phonon modes A_g^1-A_g^10, B_g^1, and B_g^2. Notably, the B_g^1 peak did not appear in samples synthesized by the VB and EFG methods, whereas A_g^7 was absent in the sample prepared using VB method. MBE-grown bulk β-Ga2O3 exhibited a blue shift in the A_g^3 mode which is a sign of increased vibrational frequencies due to increse lattice stress. In contrast, the samples syhntesised using HVPE and EFG methods displayed a red shift in the A_g^3 mode, suggesting lattice expansion. Full width at half maximum (FWHM) analysis revealed that EFG and HVPE methods resulted in narrower peaks, indicating improved crystallinity. Doping with Fe resulted in minimal changes to the Raman spectra, whereas Sn doping significantly increased the intensity of the A_g^3 peak and decreased the A_g^10 peak, reflecting notable enhancements in vibrational modes and structural properties. Moreover, the A_g^10 peak of the Sn doped Ga2O3 sample appeared narrower compared to pure and Fe-doped Ga2O3, indicating higher crystallinity in the Sn-doped sample. Overall, the study highlights the substantial effects of growth methods and doping on the structural and vibrational characteristics of β-Ga2O3, providing valuable insights for optimizing Ga2O3-based electronic and optoelectronic devices.7enβ-Ga₂O₃ Growth methodsFe- dopedSn-dopedstructural propertiesRaman spectroscopyThesis