Patent ID: 6951384
Filing Date: 2005-10-04
Classification: B41J

Abstract:
1. A method for improving thermal efficiency of ink jet heater chips of the type having a semiconductor substrate layer, a first metal resistive layer on the substrate layer, a second metal conductive layer on a first portion of the resistive layer, and the second metal conductive layer on a second portion of the resistive layer thereby defining a heater resistor element between the first and second portions of the resistive layer, the method comprising the steps of: depositing a passivation layer on the heater resistor element and second metal conductive layer; depositing a cavitation layer on the passivation layer; etching the cavitation layer to expose a portion of the passivation layer overlying the first portion of the resistive layer; depositing an inter metal dielectric layer on the cavitation layer and exposed portion of the passivation layer; removing the dielectric layer over the heater resistor element and overlying the second portion of the resistive layer; etching a via in the dielectric layer and underlying passivation layer to provide an electrical connection conduit to the second metal conductive layer overlying the first portion of the resistive layer; depositing a third metal conductive layer in the via, adjacent the dielectric layer and adjacent the cavitation layer; and removing a portion of the third metal conductive layer overlying the heater resistor element and second portion of the resistive layer to provide a metal contact for the heater chip.