| 摘要 |
PURPOSE:To improve the irregularity of printing density by sufficiently reducing the difference in applying voltage to a heat generating resistor according to a printing position, by successively forming an Ni-plating layer, a Cu-plating layer and an Ni-plating layer to the upper part of the conductor wiring layers interposed between a substrate and the under sides of a common electrode body, an external connection terminal and a driving IC ground terminal. CONSTITUTION:A common electrode body 7 and a ground terminal and external connection terminal part 8 are formed by successively forming the first Ni- plating layer 9, a Cu-plating layer 10 and the second Ni-plating layer 11 to the insulating thin film layer formed on an alumina ceramic substrate 1 and a glaze layer 2, that is, a base layer having multilayer constitution consisting of a Ta2O5 layer 3, a heat generating resistor layer 4 and an Al conductor wiring layer 5. When an external connection terminal 12 is formed into a press bonded terminal, gold plating is further applied. The heat generating resistor layer is protected by an abrasion resistant layer 3, and a bonding part for mounting driving IC and the part except the external connection terminal 12 are respectively protected by an insulating resin 14. Therefore, voltage drop difference based on circuit resistance difference is low.
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