摘要： Realizing manipulation of the photoelectric properties of wide bandgap semiconductors is a main challenge for succeeding next-generation functional optoelectronics. As an intriguing wide bandgap semiconductor, β-Ga2O3 (Eg ~ 4.9 eV) is emerging as a promising candidate for photodetectors operating in solar-blind region. Here, we show that by selecting substrates with different symmetries and lattice parameters [i.e. (100) MgO, (100) MgAl2O4 and (0001) α-Al2O3], epitaxial β-Ga2O3 films with (100)- or (2?01)-oriented could be fabricated. We found that the photoresponse characteristics are strongly correlated with the lattice mismatch and film orientation. In particular, (100)-oriented β-Ga2O3 film grown on MgO substrate with smaller lattice mismatch exhibited a 254 nm responsivity of 0.1 A·W-1 and detectivity of 4.3×1012 Jones, which are approximately an order of magnitude higher than that of the (2?01)-oriented β-Ga2O3 film. Our work may provide a strategy to develop further high performance solar-blind photodetectors.