In0.53Ga0.47As　epitaxial　films　are　grown　on　2-inch　diameter　Si　(111)　substrates　by　growing　a　low-temperature　In0.4Ga0(.6)As　buffer　layer　using　molecular　beam　epitaxy.　The　effect　of　the　buffer　layer　thickness　on　the　as-grown　In0.53Ga0.47As　films　is　characterized　by　X-ray　diffraction,　scanning　electron　microscopy,　atomic　force　microscopy　and　transmission　electron　microscopy　(TEM).　It　is　revealed　that　the　crystalline　quality　and　surface　morphology　of　as-grown　In0.53Ga0.47As　epilayer　are　strongly　affected　by　the　thickness　of　the　In0.4Ga0.6As　buffer　layer.　From　TEM　investigation,　we　understand　that　the　type　and　the　distribution　of　dislocations　of　the　buffer　layer　and　the　as-grown　In0.53Ga0.47As　film　are　different.　We　have　demonstrated　that　the　In0.4Ga0.6As　buffer　layer　with　a　thickness　of　12　nm　can　advantageously　release　the　lattice　mismatch　stress　between　the　In0.53Ga0.47As　and　Si　substrate,　ultimately　leading　to　a　high-quality　In0.53Ga0.47As　epitaxial　film　with　low　surface　roughness.　Crown　Copyright　(C)　2015　Published　by　Elsevier　B.　V.　All　rights　reserved.