Method for manufacturing bonded wafer

Abstract

The present invention is a method for manufacturing a bonded wafer including at least the steps of: forming an ion-implanted layer inside a bond wafer; bringing the ion-implanted surface of the bond wafer into close contact with a surface of a base wafer directly or through a silicon oxide film; and performing heat treatment for delaminating the bond wafer at the ion-implanted layer, wherein the heat treatment step for delaminating includes performing a pre-annealing at a temperature of less than 500° C. and thereafter performing a delamination heat treatment at a temperature of 500° C. or more, and the pre-annealing is performed at least by a heat treatment at a first temperature and a subsequent heat treatment at a second temperature higher than the first temperature. As a result, there is provided a method for manufacturing a bonded wafer having high quality, for example, mainly the reduction of defects, by forming a high bonding strength state at a lower temperature than the temperature at which the delamination is caused, in the manufacture of the bonded wafer by the Smart Cut method (registered trademark).

Dependencies are inferred from the claim text.