【Member Papers】Growth and Properties of 4-Inch Fe Doped (010) β-Gallium Oxide Using Vertical Bridgman Method

      Researchers from the Zhejiang University have published a dissertation titled "Growth and Properties of 4-Inch Fe Doped (010) β-Gallium Oxide Using Vertical Bridgman Method" in Journal of Synthetic Crystals.

Abstract

      In this study， a self-built vertical Bridgman （VB） system was utilized to grow large-size， high-quality Fe-doped β-Ga₂O₃ single crystals. Through iterative thermal field optimization via simulation， slightly convex solid-liquid interface and appropriate temperature gradient were achieved. The as-grown crystal was further processed into a high-quality 4-inch （010） oriented semi-insulating substrate. Comprehensive evaluations of crystallinity， surface morphology， and electrical properties were carried out. The substrate exhibits no macroscopic defects such as cracks. Multi-point X-ray rocking curve measurements show full width at half maximum （FWHM） values all below 50″， indicating superior crystalline quality. Surface topography tests reveal a maximum roughness of 0.074 nm， local thickness variation （LTV） below 3.4 μm， total thickness variation （TTV） of 4.157 μm， warp of 5.886 μm， and bow of 1.103 μm， demonstrating excellent processing quality. Moreover， the substrate displays high average resistivity of approximately 7.9×10¹⁰ Ω·cm with an in-plane inhomogeneity of about 7.77%， underscoring the effectiveness of VB method in achieving uniform doping distribution and its potential for radio frequency （RF） and microwave device applications.

DOI: 

10.16553/j.cnki.issn1000-985x.2025.0159