MANUFACTURE OF SEMICONDUCTOR DEVICE

PURPOSE:To simplify the processes by a method wherein an oxide film layer is buried in an isolated region by ion implantation to bury a groove cut in a semiconductor substrate by etching process in an epitaxial layer to be used as an active region. CONSTITUTION:A resist 12 patterned on a silicon substrate 1 is etched to cut a groove. Then, after etching process, the surface is implanted with ion and annealed after removing the resist 12 to form an n type high concentration diffused layer 4. First, the diffused layer 4 after ion-implanted with oxygen is annealed to form an oxide film 5. Second, an n type epitaxial layer 13 is grown in the groove to form the resist 12 thereon and then etched to finish the etching process when the topmost part is exposed. Finally, a collector wall is formed around the peripheral part of groove by diffusion further to form a base layer 7, an emitter layer 8 and respective electrodes 10a-11c.