Patent attributes
The present invention provides a method for manufacturing an SOI substrate by which an oxygen ion is implanted from at least one of main surfaces of a single-crystal silicon substrate to form an oxygen-ion-implanted layer and then an oxide film-forming heat treatment that changes the formed oxygen-ion-implanted layer into a buried oxide film layer is performed with respect to the single-crystal silicon substrate to manufacture the SOI substrate, the method comprising: implanting a neutral element ion having a dose amount of 1×1012 atoms/cm2 or above and less than 1×1015 atoms/cm2 into a back surface to form an ion-implanted damage layer after performing the oxide film-forming heat treatment; and gettering a metal impurity in the ion-implanted damage layer by a subsequent heat treatment to enable reducing a metal impurity concentration on a front surface side. Thereby, there is provided a method for manufacturing an SOI substrate having a gettering layer on a back surface thereof in a simple process at a low cost.
