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Researchers have been aggressively investigating group-IV (Ge, SiGeSn, GeSn) optoelectronic materials to realize tunable wavelength lasers, photodetectors, and transistors. By exploiting strain and bandgap engineering of these materials via choice of substrate orientation and intelligent buffer engineering as well as precise control of Sn alloy composition during material synthesis, it will offer widespread device applications. There is an opportunity to improve the device-level quality of GeSn material systems along with higher Sn incorporation that face growth challenges during epitaxy. The current research work presents the substrate orientation and misorientation (100)/2˚, (100)/6˚, (110), (111) mediated epitaxial GeSn and Ge optoelectronic materials synthesized via MBE and analyzed using several analytical tools. X-ray analysis demonstrated high quality GeSn materials with less broadening and good symmetricity on (100) compared to (110) GeSn materials. Minority carrier lifetimes of these GeSn epilayers were extracted as > 400 ns for the (100) substrate misoriented by 6˚ towards [110] direction. Raman spectroscopy measurements were performed to study the vibrational properties, where the LO phonon wavenumber shifts at ωLO = 301.11 ± 0.8 cm¬–1 from (100)/2˚, (100)/6˚ and (110) oriented GeSn epilayers that were synthesized in equivalent growth conditions. Cross-sectional TEM of (100)/2˚ GeSn sample was performed that revealed good quality GeSn material on GaAs. Elimination of the interfaced electronic dipole charge effects, that destabilize the group-IV/group III-V heterointerface and further layer growths, is attributed to aid in achieving superior quality GeSn epitaxial materials over a (100) substrate that is misoriented by 6˚ towards the [110] direction. This substrate offcut will enable to annihilate antiphase domains due to polar-on-non-polar epitaxial growth, which further reduce non-radiative recombination centers in GeSn material. Hence, growth of GeSn material on misoriented (100) substrate offers two-fold benefits: (i) reduced active defects at the GeSn/III-V heterointerface, and (ii) self-annihilation of the antiphase domain boundaries for enhancing the efficiency of optical devices.