Patent ID: 6616269
Filing Date: 2003-09-09
Classification: B41J

Abstract:
A substrate for an ink jet print head that uses thermal energy to eject ink, said substrate comprising:a film structure having a plurality of films laminated on said substrate, the plurality of films including a first electric wire film, a heater film and a second electric wire film formed one upon the other in that order on said substrate, a combination of the heater film and the second electric wire film allowing the thermal energy to be generated on a portion where the second electric wire film is not laminated on the heater film; wherein an electrode pad portion, which is formed at a part of said film structure to make an electrical connection to a power source through a ball bump, is formed by an exposed part of the first electric wire film, the ball bump being formed on the exposed part of the first electric wire film, and a thickness of the first electric wire film is larger than that of the second electric wire film.