Annealing method for improving bonding strength

Abstract

The present disclosure provides an annealing method for improving interface bonding strength of a wafer. The method includes: providing a substrate, the substrate having a bonding interface; performing a first annealing step, wherein the first annealing step is practiced in an oxygen-containing atmosphere, and an oxidation protection layer is formed on a surface of the substrate through the annealing step; and performing a second annealing step upon the first annealing step, wherein a temperature of the second annealing step is higher than that of the first annealing step, and the second annealing step is practiced in a nitrogen-free environment.

Dependencies are inferred from the claim text.