Printed circuit board

A printed circuit board, comprising:

• a first substrate including a first wiring layer;
• a second substrate disposed on the first substrate and including a second wiring layer;
• a metal layer disposed between the first and second substrates;
• and
• a bonding layer disposed between the first and second substrates,
• wherein a wiring line having a minimum line width among wiring lines of the second wiring layer has a line width smaller than a line width of a wiring line having a minimum line width among wiring lines of the first wiring layer.

A method of manufacturing a printed circuit board, the method comprising:

• preparing a first substrate including a plurality of first wiring layers and having a first metal layer formed on an outermost side;
• forming a first inorganic insulating film covering at least a portion of the first metal layer on the outermost side of the first substrate;
• preparing a second substrate including a plurality of second wiring layers and having a second metal layer formed on an outermost side;
• forming a second inorganic insulating film covering at least a portion of the second metal layer on the outermost side of the second substrate;
• and
• bonding the first and second substrates to each other such that the first and second inorganic insulating films are bonded to each other and the first and second metal layers are bonded to each other,
• wherein each of the first and second substrates includes an organic material.

A printed circuit board, comprising:

• a first substrate including a plurality of first insulating layers, a plurality of first wiring layers disposed on or in the plurality of first insulating layers, and a plurality of first via layers penetrating at least one of the plurality of first insulating layers, respectively;
• a second substrate disposed on the first substrate and including a plurality of second insulating layers, a plurality of second wiring layers disposed on or in the plurality of second insulating layers, respectively, and a plurality of second via layers penetrating at least one of the plurality of second insulating layers, respectively;
• a metal layer disposed between the first and second substrates to connect a via layer among the plurality of first via layers which is closest to the second substrate and a via layer among the plurality of second via layers which is closed to the first substrate to each other;
• and
• an insulating bonding layer disposed between the first and second substrates to connect to the first and second substrates to each other,
• wherein the via layer among the plurality of first via layers which is closest to the second substrate and the plurality of second via layers are tapered in opposite directions.

A printed circuit board, comprising:

• a first substrate including a plurality of first insulating layers, a plurality of first wiring layers disposed on or in the plurality of first insulating layers, and a plurality of first via layers penetrating at least one of the plurality of first insulating layers, respectively;
• a second substrate disposed on the first substrate and including a plurality of second insulating layers, a plurality of second wiring layers disposed on or in the plurality of second insulating layers, respectively, and a plurality of second via layers penetrating at least one of the plurality of second insulating layers, respectively;
• a metal layer disposed between the first and second substrates to connect a via layer among the plurality of first via layers which is closest to the second substrate and a via layer among the plurality of second via layers which is closed to the first substrate to each other;
• and
• an insulating bonding layer disposed between the first and second substrates to connect to the first and second substrates to each other,
• wherein an outermost via layer of the plurality of second via layers, connected to an outermost wiring layer of the plurality of second wiring layers, has a tapered shape such that a width thereof increases in a direction towards the metal layer.