Patent ID: 7736998
Filing Date: 2010-06-15
Classification: H01L,Y10T

Abstract:
1. A method for manufacturing a silicon-on-insulator (SOI) substrate, comprising: forming an oxide film in at least a surface of an active layer-forming substrate including a single-crystal semiconductor; implanting hydrogen ions from the surface of the active layer-forming substrate so as to form an ion-implanted region within the active layer-forming substrate; subjecting the active layer-forming substrate to a first heat treatment in a state in which the active layer-forming substrate contacts, through the oxide film, with a base substrate including a single-crystal semiconductor so as to separate the active layer-forming substrate from the base substrate at the ion-implanted region and form an active layer on a surface of the base substrate, thereby, forming a bonded substrate; measuring film thickness throughout the active layer; selectively using only reactive radicals generated by a plasma etching process to etch more material at the surface of the active layer in areas where the active layer has a large thickness and etch less material at the surface of the active layer in areas where the active layer has a small thickness based on the film thickness data obtained by the above measurement, in such a way as to etch off at least 100 nm of the active layer and thin the active layer to a predetermined thickness; additionally plasma-etching a boundary area between an inactive region and an active region at the periphery of the bonded substrate by a thickness equal to that of the active layer prior to plasma etching, based on the film thickness data; and subjecting the plasma-etched bonded substrate to a second heat treatment so as to enhance the bond strength.