Printed circuit board and manufacturing method thereof
A printed circuit board according to an embodiment includes: an insulation layer including a recess portion; and a connection pad disposed on the recess portion of the insulation layer and protruded from the recess portion, wherein the connection pad may include a protrusion and a concave portion that is lower than the protrusion, and a surface height of the protrusion of the connection pad may be substantially the same as or less than a surface height of the insulation layer.
1 . A printed circuit board comprising: an insulation layer including a recess portion; and a connection pad disposed in the recess portion of the insulation layer and protruded from a bottom side of the recess portion, wherein the connection pad includes a protrusion and a concave portion that is lower than the protrusion, a surface height of the protrusion of the connection pad is less than a surface height of the insulation layer; wherein the connection pad is exposed in the cavity; wherein the protrusion of the connection pad is disposed in a center portion of the connection pad, and the concave portion surrounds the protrusion; and wherein a cross-section of the protrusion has a trapezoidal shape of which a width is narrowed as it goes upward.
2 . The printed circuit of claim 1 , wherein
a surface of the concave portion is substantially planar.
3 . The printed circuit of claim 2 , wherein
a surface height of the concave portion of the connection pad is higher than a height of the bottom side of the recess portion and is lower than a surface height of the insulation layer.
4 . The printed circuit of claim 3 , wherein
a difference between the surface height of the insulation layer and the surface height of the concave portion is about 1 μm to about 6 μm.
5 . The printed circuit of claim 1 , wherein
a cross-section of the protrusion has a trapezoidal shape of which a width is narrowed as it goes upward.
6 . The printed circuit of claim 5 , wherein
a surface of the concave portion is substantially planar.
7 . The printed circuit of claim 6 , wherein
a surface height of the concave portion of the connection pad is higher than a height of the bottom side of the recess portion and is lower than a surface height of the insulation layer.
8 . The printed circuit of claim 1 , further comprising:
a first protection layer covering a portion of one surface of the insulating layer, the recess portion being recessed from the one surface of the insulating layer.
9 . The printed circuit of claim 8 , further comprising:
a second protection layer covering another surface of the insulating layer opposing the one surface of the insulating layer.