Wiring structure, forming method of the same and printed wiring board
There is disclosed a wiring structure or the like capable of sufficiently improving a connection property between a body to be wired and a wiring pattern (layer) connected to the body to be wired. In a semiconductor-embedded substrate 1 , conductive patterns 13 are formed on opposite surfaces of a core substrate 11 , and a semiconductor device 14 is arranged in a resin layer 16 laminated on the core substrate 11 . The resin layer 16 is provided with the conductive pattern 13 and bumps 14 p of the semiconductor device 14 , and via-holes 19 a, 19 b are formed through upper portions of the resin layer. In the via-holes 19 a, 19 b , via-hole electrode portions 23 a, 23 b are connected to the conductive pattern 13 and the bumps 14 p of the semiconductor device 14 . The via-hole electrode portions 23 a, 23 b are provided so that each via-hole electrode portion has a concave portion at an upper surface thereof and so that a side wall thereof including an edge portion of the concave portion does not come in contact with an inner wall of the via-hole 19 a or 19 b.
1 . A wiring structure comprising:
an insulating layer provided with a connection hole;
a body to be wired which is arranged so that at least a part of the body to be wired is exposed to a bottom portion of the connection hole; and
a wiring layer connected to the body to be wired in the connection hole, having a concave portion in at least a part of an upper surface thereof, and provided so that a side wall thereof including an edge portion of the concave portion does not come in contact with an inner wall of the connection hole.
2 . The wiring structure according to claim 1 , wherein the wiring layer includes a portion in which a sectional area increases from the edge portion of the concave portion toward the body to be wired.
3 . The wiring structure according to claim 1 , wherein the wiring layer includes a portion in which a sectional area increases from a portion connected to the body to be wired toward an opening of the connection hole.
4 . The wiring structure according to claim 1 , wherein the wiring layer is provided so as to define a spatial area where at least a part of the inner wall of the connection hole does not come in contact with the wiring layer.
5 . The wiring structure according to claim 1 , wherein a width of an upper end of the wiring layer is set to be smaller than an opening width diameter of the connection hole.
6 . The wiring structure according to claim 1 , wherein the wiring layer is provided so as to cover the whole exposed surface of the body to be wired which is exposed to the bottom portion of the connection hole.
7 . A printed wiring board in which wiring structures are arranged, each wiring structure comprising: an insulating layer provided with a connection hole; a body to be wired which is arranged in a lower portion or an inner portion of the insulating layer so that at least a part of the body to be wired is exposed to a bottom portion of the connection hole; and a wiring layer connected to the body to be wired in the connection hole, having a concave portion in at least a part of an upper surface thereof, and provided so that a side wall thereof including an edge portion of the concave portion does not come in contact with an inner wall of the connection hole.
8 . A method for forming a wiring structure, comprising:
an insulating layer forming step of forming an insulating layer on a body to be wired;
a connection hole forming step of forming at least one connection hole in the insulating layer so that at least a part of the body to be wired is exposed; and
a wiring layer connection step of connecting the body to be wired to a wiring layer in the connection hole,
the wiring layer connection step being configured to form the wiring layer so that a concave portion is formed in at least a part of an upper surface of the wiring layer and so that a side wall thereof including an edge portion of the concave portion of the wiring layer does not come in contact with an inner wall of the connection hole.