Semiconductor package and method of forming the same, printed circuit board, and electronic device

A semiconductor package comprising:

• a first PCB including a first slit at a substantially central portion thereof;
• a first semiconductor chip mounted on the first PCB;
• a first upper molding layer covering the first semiconductor chip;
• a first lower molding layer filling the first slit and covering a portion of an undersurface of the first PCB;
• a second PCB disposed on the first semiconductor chip;
• and
• a second semiconductor chip mounted on the second PCB,
• wherein the first PCB further includes a first connecting recess at a side surface thereof, and the first upper molding layer and the first lower molding layer are in contact with each other at the first connecting recess.

A PCB (printed circuit board) comprising:

• a chip region including a mounting region having a slit extending through at least a portion of the PCB;
• and
• a scribe region located around the chip region,
• wherein the chip region includes a molding hole disposed between the scribe region and the slit.