Electronic substrate device

Abstract

An electronic substrate device capable of reliably and stably transferring heat generated by a heat generating component to a base member serving as a heat dissipator without intermediation of an electronic substrate. An electronic substrate device according to the present invention, in which a base member includes a central protruding portion which is accommodated in a penetrating portion while facing a die pad through an intermediary first gap, and first separated protruding portions provided around the central protruding portion have a height dimension smaller than that of the central protruding portion, the first separated protruding portions having a top surface which abuts a rear surface portion of the electronic substrate to form a second gap, and in which a first heat transfer bond which is a heat conductive adhesive is applied to the first gap and the second gap communicating with the first gap.

1 . An electronic substrate device, comprising:
 a heat conductive base member, which is fixed to an installation portion through an intermediation of attachment parts;   a cover member, which is fixed to an outline peripheral portion formed so as to surround an outer peripheral edge portion of the base member;   an electronic substrate, which is placed in an interior space between the base member and the cover member, and comprises a rear surface portion facing with the base member and a front surface portion facing with the cover member; and   a heat generating component, which is mounted on the electronic substrate, and comprises a plurality of connecting terminals, which are electrically connected, by soldering, to the electronic substrate, and a die pad serving as a heat transfer member, a heat generating element attached to the die pad, and the rear surface portion of the electronic substrate,   wherein the base member comprises an accommodation recess, which accommodates the heat generating component through an intermediation of a first gap, and a first separated protruding portion, which is provided around the accommodation recess, and has a top surface, which abuts the rear surface portion of the electronic substrate to form a second gap, and   wherein a first heat transfer bond, which is a heat conductive adhesive, is applied to the first gap and the second gap communicating with the first gap.   
     
     
         2 . An electronic substrate according to  claim 1 ,
 wherein the electronic substrate which is covered by the cover member, comprises a penetrating portion, which penetrates through the front surface portion into the rear surface portion,   wherein a heat sink, which comprises a central protruding portion which is accommodated in the penetrating portion while facing with the die pad through an intermediation of a third gap is placed on a front surface portion side, and wherein a second heat transfer bond, which is a heat conductive adhesive is applied to the third gap.   
     
     
         3 . An electronic substrate device according to  claim 2 ,
 wherein the heat sink comprises second separated protruding portions, which are provided around the central protruding portion, and have a height dimension smaller than that of the central protruding portion, the second separated protruding portions having a top surface which abuts the front surface portion of the electronic substrate to form a fourth gap,   wherein dimensions of the first separated protruding portion and the second separated protruding portions are determined such that, when the base member and the cover member are integrated with each other by a joint means, a relationship between a first force (F 1 ) and a second force (F 2 ) becomes F 2 ≦F 1 , the first force (F 1 ) pressing the heat generating component to a cover member side through an intermediation of the first heat transfer bond, the second force (F 2 ) pressing the heat generating component to a base member side through an intermediation of the second heat transfer bond, and   wherein watercourse resistance in which the first heat transfer bond flows outsides is higher than watercourse resistance in which the second heat transfer bond flows outsides.   
     
     
         4 . An electronic substrate device according to  claim 1 , wherein a waterproof sealing material, which is a liquid silicon resin material of cold setting type which is the same as or homogeneous to the first heat transfer bond and the second heat transfer bond, is applied between an opening end surface of the cover member and the outline peripheral portion of the base member. 
     
     
         5 . An electronic substrate device according to  claim 2 , wherein the cover member is made of a heat conductive material, and integrally formed with the heat sink. 
     
     
         6 . An electronic substrate device according to  claim 1 , wherein a surface of the base member side of the first gap, to which the first heat transfer bond is applied, is subjected to an alumite treatment which provides electrical insulation resistance. 
     
     
         7 . An electronic substrate device according to  claim 2 , wherein a surface of the heat sink side of the third gap, to which the second heat transfer bond is applied, is subjected to an alumite treatment which provides electrical insulation resistance.