Ga2O3-based　solar-blind　photodetectors　(SBPDs)　with　typical　Schottky　structure　usually　exhibit　low　responsivity　and　rapid　saturation　as　reverse　bias　increase　in　the　lack　of　avalanche　gain.　In　this　study,　large-area　photosensitive　Ga2O3　single-crystalline　films　were　homoepitaxially　grown　by　MOCVD,　enabling　the　fabrication　of　high-performance　SBPDs.　At　a　low　bias　of　-5　V,　the　device　exhibits　an　ultrahigh　photoresponsivity　of　27.5　A/W　and　a　photo-to-dark　current　ratio　of　2.4　×　105　with　an　ultralow　dark　current　of　3.74　×　10-8A/cm2,　superior　to　most　similar　Ga2O3　SBPDs　reported　to　date.　Furthermore,　without　sacrificing　the　response　speed　(tr　=100　ns,　td　=　240.5μs),　the　device　attained　a　peak　external　quantum　efficiency　of　1.5　×　104%.　This　stems　from　the　ultrahigh　photoconductive-like　gain　caused　by　significant　mobility　differences　of　photogenerated　carriers　under　reverse　bias　in　high-quality　Ga2O3　homo-epilayer.　©　1980-2012　IEEE.