PURPOSE: To prevent withstand voltage deterioration by forming a conductive layer through an organic insulating layer, inorganic insulating layer, and an organic adhesive layer on the surface of a metal plate.
CONSTITUTION: An organic insulating layer 21 is formed on the surface of a metal plate 1, an inorganic insulating layer 22 is formed on top of that, and a conductive layer 5 is formed on top of that via an organic adhesive layer 23. A metallic nitride such as aluminum oxide is used as a material for the inorganic insulating layer 22. Although there are no specific restrictions on the thickness of the organic insulating layer 23, a proper thickness is selected depending on the thickness of the insulating layer 2. Since the base of the inorganic insulating layer 22 is an organic high molecule material, it needs to be formed at low temperature under the transition point of glass which is an insulating layer material. The organic adhesive layer 24 is for bonding the conductive layer 5 to the inorganic insulating layer 23 and its material is normally the same as the one for the organic insulating layer 21. Also, in view of the bonding strength of the conductive layer 5, when the insulating layer thickness is 150μm its thickness is preferably 5 to 20% of it or 1.5 to 30μm.
KATO JUNICHI
MIMORI SEIJI
OBATA KAZUHITO
NAGAO KENICHI
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