Memory card ( 1 ) includes at least semiconductor chip ( 3 ), circuit board ( 2 ) with semiconductor chip ( 3 ) mounted on main surface ( 21 ), having at least rigidity reducing portion ( 23 ) formed in main surface ( 21 ) or in a linear region of surface ( 22 ) opposite to the main surface, and cover portion ( 71 ) for covering semiconductor chip ( 3 ) on main surface ( 21 ) of circuit board ( 2 ), wherein circuit board ( 2 ) has a plurality of convex regions ( 201 ) which flex in a convex shape toward main surface ( 21 ) due to rigidity reducing portion ( 23 ).
1. A memory card comprising:
a semiconductor chip;
a circuit board having a main surface on which the semiconductor chip and an electrode are mounted, the circuit board having at least one first groove formed inwardly from the main surface into a body of the circuit board and at least one second groove formed inwardly from a surface opposite to the main surface into a body of the circuit board; and
a cover portion for covering the semiconductor chip at a main surface side of the circuit board, wherein:
the number of said at least one first groove is greater than the number of said at least one second groove, and
said at least one first groove and said at least one second groove are provided on the circuit board itself, and do not penetrate through the circuit board, and
the circuit board is in a form of a plate having a constant thickness except for the first and second grooves.
2. The memory card of claim 1 , wherein said at least one first groove is at least opposed to the semiconductor chip.
3. The memory card of claim 1 , wherein said at least one first groove is perpendicular to said at least one second groove in the circuit board.
4. The memory card of claim 1 , further comprising another semiconductor chip mounted on the circuit board adjacent to the semiconductor chip,
wherein at least said at least one first groove is positioned between the semiconductor chip and the another semiconductor chip.
5. The memory card of claim 1 , wherein the cover portion is made of thermoplastic resin formed to cover the semiconductor chip on the circuit board.
6. The memory card of claim 1 , wherein the cover portion has a concave portion for accommodating the semiconductor chip, which is a molded part mounted on the circuit board with the concave opening toward the circuit board.
7. The memory card of claim 1 , wherein at least a part of said at least one first groove is disposed below the semiconductor chip.
8. The memory card of claim 1 , wherein the body of the circuit board is made of resin.