Printed circuit board

A printed circuit board, comprising:

• a first insulating layer;
• a first conductor-pattern layer disposed on a first surface of the first insulating layer;
• a first recess disposed in a second surface of the first insulating layer opposing the first surface of the first insulating layer;
• a second conductor-pattern layer disposed in the first recess;
• a first metal post penetrating the first insulating layer, connecting the first and second conductor-pattern layers to each other, and having one end exposed to a bottom surface of the first recess;
• a second insulating layer having one surface in contact with the second surface of the first insulating layer;
• a second recess disposed in another surface of the second insulating layer opposing the one surface of the second insulating layer;
• a third conductor-pattern layer disposed in the second recess;
• a second metal post penetrating the second insulating layer and connecting the second and third conductor-pattern layers to each other;
• a solder resist disposed on the second insulating layer and having an opening to expose a portion of the third conductor-pattern layer;
• a third insulating layer disposed on an opposing side of the first insulating layer with respect to the second insulating layer such that the first insulating layer is disposed between the second insulating layer and the third insulating layer;
• a fourth conductor-pattern layer disposed on a first surface of the third insulating layer;
• a third recess disposed in a second surface of the third insulating layer opposing the first surface of the third insulating layer;
• a fifth conductor-pattern layer disposed in the third recess;
• and
• a third metal post penetrating the third insulating layer, connecting the fourth and fifth conductor-pattern layers to each other, and having one end protruding from a bottom surface of the third recess towards the second insulating layer,
• wherein the first and second insulating layer have the same material, and
• wherein an upper surface of the first metal post does not extend in an upward direction beyond a lower surface of the second conductor-pattern layer disposed in the first recess.