Wiring substrate and manufacturing method thereof

A wiring substrate, comprising:

• a substrate comprising;
• at least one of a front surface and a rear surface configured as a mounting surface for components, the front and rear surfaces being planar surfaces that are parallel to each other;
• a circuit pattern, and
• a high thermal conductive layer formed by a plate-shaped metal core at a center position of the substrate in a thickness direction of the substrate, the thickness direction being perpendicular to the front and rear surfaces;
• a concave section formed in a side edge part of the substrate and exposed to both the front surface and the rear surface of the substrate;
• and
• a plurality of connection terminals extended from a side surface portion of the concave section and bent in a direction perpendicular to a surface of the substrate, the side surface portion being substantially perpendicular to the front and rear surfaces of the substrate,
• wherein a portion of the connection terminals is disposed to penetrate inside the side surface portion to thereby fix the connection terminals to the substrate,
• wherein a section of the connection terminals only contacts the substrate at the side surface portion,
• wherein the connection terminals are installed in the side surface portion of the concave section in a longitudinal direction,
• wherein the substrate includes a first wide portion at one side of the substrate and a second wide portion at the other side of the substrate in an arranging direction of the connection terminals,
• wherein a width of the first wide portion is larger than a width of the second wide portion in the arranging direction of the connection terminals,
• wherein the first wide portion comprises:
• first and second outer side surfaces that are parallel to the arranging direction of the connection terminals and opposite to each other, and
• a third outer side surface that is perpendicular to the first and second outer side surfaces and continuously extends from the first outer side surface to the second outer side surface, and
• wherein the wiring substrate further comprises insulation layers contacting and covering opposite sides of the high thermal conductive layer, the opposite sides being parallel to the front and rear surfaces of the substrate, and at least one of the insulation layers being formed in between the circuit pattern and the high thermal conductive layer in the thickness direction of the substrate.