Suspension board with circuit and producing method thereof

Abstract

A suspension board with circuit includes a metal supporting board, an insulating base layer formed on one side of the metal supporting board in a thickness direction thereof, a conductive layer, and an insulating cover layer formed on the one side of the insulating base layer to cover the conductive layer. Either one of the insulating base layer and the insulating cover layer includes an opening extending therethrough in the thickness direction. The conductive layer includes a wire formed on the one side of the insulating base layer, and a connection terminal electrically connected to the wire and exposed from the opening to be capable of electrical connection to an electronic element. The suspension board with circuit further includes a protective layer for protecting the connection terminal exposed from the opening.

1 .- 9 . (canceled) 
     
     
         10 . A method of producing a suspension board with circuit, comprising the steps of:
 preparing a metal supporting board;   laminating, on one side of the metal supporting board in a thickness direction thereof, an insulating layer including a depressed portion which is recessed from the one side of the insulating layer in the thickness direction toward the other side thereof in the thickness direction;   laminating a conductive layer including a wire formed on the one side of the insulating layer in the thickness direction, and a connection terminal electrically connected to the wire and filling the depressed portion to be capable of electrical connection to an electronic element;   partially removing the metal supporting board to expose a surface of the insulating layer which is located on the other side thereof in the thickness direction in a region which overlaps at least the depressed portion when projected in the thickness direction;   partially removing the insulating layer to allow the depressed portion to extend through the insulating layer in the thickness direction and form an opening so as to expose a surface of the connection terminal which is located on the other side thereof in the thickness direction, while forming a recessed portion which is recessed in a peripheral edge portion of the opening from the surface of the insulating layer which is located on the other side thereof in the thickness direction toward the one side thereof in the thickness direction; and   forming a protective layer made of a conductive material on the surface of the connection terminal which is located on the other side thereof in the thickness direction and exposed from the opening.   
     
     
         11 . A method of producing a suspension board with circuit, comprising the steps of:
 preparing a metal supporting board;   laminating, on one side of the metal supporting board in a thickness direction thereof, an insulating base layer including a depressed portion which is recessed from the one side of the insulating base layer in the thickness direction toward the other side thereof in the thickness direction;   laminating a conductive layer including a wire formed on the one side of the insulating base layer in the thickness direction, and a connection terminal electrically connected to the wire and filling the depressed portion to be capable of electrical connection to an electronic element;   forming an insulating cover layer covering the wire and including an opening which exposes the connection terminal on the one side of the insulating base layer in the thickness direction; and   forming a protective layer made of a conductive material on a surface of the connection terminal exposed from the opening which is located the one side thereof in the thickness direction.   
     
     
         12 . The method of producing a suspension board with circuit according to  claim 10 , wherein at the step of forming the opening and the recessed portion, the recessed portion is formed to be located, in the thickness direction, at the one side of a surface of the metal supporting board which is located on the one side thereof in the thickness direction. 
     
     
         13 . The method of producing a suspension board with circuit according to  claim 10 , wherein at the step of laminating the insulating base layer, the insulating layer including the depressed portion is formed by gradation exposure. 
     
     
         14 . The method of producing a suspension board with circuit according to  claim 11 , wherein at the step of laminating the insulating layer, the insulating base layer including the depressed portion is formed by gradation exposure.