Patent ID: 8230596

Claim:
A method of manufacturing a liquid ejection head, comprising the steps of: bonding together a diaphragm made of a stainless steel substrate containing iron, chromium and aluminum, and a pressure chamber formation substrate which has a space for a pressure chamber and is made of stainless steel containing chromium and aluminum, by diffusion bonding, in such a manner that a structural body including the diaphragm and the pressure chamber formation substrate is formed; carrying out a first heat treatment of the structural body so as to form an aluminum oxide film on a surface of the structural body and form a chromium oxide film between the aluminum oxide film and the structural body; forming a lower electrode on the aluminum oxide film; forming a piezoelectric body on a surface of the lower electrode reverse to a surface of the lower electrode on which the chromium oxide film and the aluminum oxide film are formed; forming an upper electrode on a surface of the piezoelectric body reverse to a surface of the piezoelectric body on which the lower electrode is formed; and calcining the piezoelectric body by carrying out a second heat treatment of the structural body in which the piezoelectric body is formed on the diaphragm.