MULTI-LAYER WIRING BOARD AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a multi-layer wiring board and a semiconductor device which can be manufactured inexpensively and whose thickness can be thinned in the multi-layer wiring board wherein a wiring layer (12) and an insulation layer (10) are alternately laminated and at least a pair of the wiring layers arranged on the surface and the rear face of the insulation layer are electrically connected through a connection part (28) formed by penetrating the insulation layer. SOLUTION: III the multi-layer wiring board, a plurality of the wiring layers and the insulation layer laminate and form the wiring board forming the wiring layer on only one surface of plate-like or sheet-like insulation layers so that the wiring layer and the insulation layer are mutually positioned, the connection part extends a part of the wiring layer of the wiring board on the area of an opening part (16) formed by penetrating the insulation layer of the wiring board to forms an extension part (30), and the extension part and the wiring layer of the other wiring board adjoined and laminated are electrically connected through a low melting point metal part (32).