| 摘要 |
In the electrode pads in the ink jet print head substrate that uses ball bumps, bonding of the ball bumps is carried out in satisfactory condition despite reduced thickness of films in the substrate. In an ink jet print head substrate, which has a heater film constituting the heater portions, a second electric wire in electrical contact with the heater film to supply it with electric power, and a first electric wire constituting a common electrode of a matrix wire for selectively driving the heater portions, the first electric wire is used as the electrode pads to which the ball bump is joined. The first electric wire does not need to be reduced in thickness even when the thickness of the protective film is reduced. Thus, an ultrasonic wave can be transferred well to the electrode pad during ultrasonic bonding.
|
