Circuit board and manufacturing method thereof
A circuit board includes: an insulating layer, a solder resist layer disposed on the insulating layer and having first and second openings; first and second connection pads respectively disposed within the first and second openings on the insulating layer; and first and second conductive layers respectively disposed on the first and second connection pads, and configured to protrude more than an upper surface of the solder resist layer and to have different thicknesses. Each of the first and second conductive layers includes a lower conductive layer disposed on a corresponding one of the first and second connection pads and an upper conductive layer disposed on an upper surface of the lower conductive layer.
1 . A circuit board comprising:
an insulating layer;
a solder resist layer disposed on the insulating layer and having first and second openings;
first and second connection pads respectively disposed within the first and second openings on the insulating layer;
a first conductive layer disposed on the first connection pad and protruding more than an upper surface of the solder resist layer; and
a second conductive layer disposed on the second connection pad and protruding more than the upper surface of the solder resist layer,
wherein the first conductive layer and the second conductive layer have different thicknesses, and
each of the first and second conductive layers includes a lower conductive layer disposed on a corresponding one of the first and second connection pads and an upper conductive layer disposed on an upper surface of the lower conductive layer.
2 . The circuit board of claim 1 , wherein
the first and second conductive layers are respectively disposed in the first and second openings.
3 . The circuit board of claim 1 , wherein
a portion of a side surface of the lower conductive layer is in contact with the solder resist layer, and
a side surface of the upper conductive layer is spaced apart from the solder resist layer.
4 . The circuit board of claim 1 , wherein
the upper conductive layer covers only the upper surface of the lower conductive layer among a side surface and the upper surface of the lower conductive layer.
5 . The circuit board of claim 1 , wherein
thicknesses of the lower conductive layers of the first and second conductive layers with respect to upper surfaces of the first and second connection pads are different from each other.
6 . The circuit board of claim 1 , wherein
an upper surface of the upper conductive layer is flat and parallel to a first surface of the insulating layer on which the first and second connection pads are disposed.
7 . The circuit board of claim 6 , wherein
the upper conductive layer is disposed at a higher position than the upper surface of the solder resist layer along a direction perpendicular to the first surface of the insulating layer.
8 . The circuit board of claim 1 , wherein
a width of the upper conductive layer of the first conductive layer is wider than a maximum width of the first connection pad.
9 . The circuit board of claim 8 , wherein
a width of the lower conductive layer of the first conductive layer at an interface between the lower conductive layer and the upper conductive layer of the first conductive layer is wider than the maximum width of the first connection pad.
10 . The circuit board of claim 1 , wherein
the first connection pad, the lower conductive layer of the first conductive layer, and the upper conductive layer of the first conductive layer include different materials.
11 . The circuit board of claim 10 , wherein
the first connection pad includes copper, the lower conductive layer of the first conductive layer includes nickel, and the upper conductive layer of the first conductive layer includes gold.
12 . The circuit board of claim 1 , wherein
the first connection pad and the second connection pad have substantially the same thickness.
13 . A circuit board comprising:
an insulating layer;
a solder resist layer disposed on the insulating layer and having first and second openings;
first and second connection pads respectively disposed within the first and second openings on the insulating layer;
a first conductive layer disposed on the first connection pad and protruding more than an upper surface of the solder resist layer; and
a second conductive layer disposed on the second connection pad and protruding more than the upper surface of the solder resist layer,
wherein the first conductive layer and the second conductive layer have different thicknesses,
each of the first and second conductive layers includes a lower conductive layer disposed on a corresponding one of the first and second connection pads and an upper conductive layer disposed on an upper surface of the lower conductive layer, and
the lower conductive layer is in physical contact with the solder resist layer.
14 . The circuit board of claim 13 , wherein
the first and second conductive layers are respectively disposed in the first and second openings.
15 . The circuit board of claim 13 , wherein
a portion of a side surface of the lower conductive layer is in physical contact with the solder resist layer, and
a side surface of the upper conductive layer is spaced apart from the solder resist layer.
16 . The circuit board of claim 13 , wherein
the upper conductive layer covers only the upper surface of the lower conductive layer among a side surface and the upper surface of the lower conductive layer.
17 . The circuit board of claim 13 , wherein
thicknesses of the lower conductive layers of the first and second conductive layers with respect to upper surfaces of the first and second connection pads are different from each other.
18 . The circuit board of claim 13 , wherein
an upper surface of the upper conductive layer is flat and parallel to a first surface of the insulating layer on which the first and second connection pads are disposed.
19 . The circuit board of claim 13 , wherein
the first connection pad, the lower conductive layer of the first conductive layer, and the upper conductive layer of the first conductive layer include different materials.
20 . The circuit board of claim 19 , wherein
the first connection pad includes copper, the lower conductive layer of the first conductive layer includes nickel, and the upper conductive layer of the first conductive layer includes gold.