Semiconductor device and method of manufacturing the same

1. A method for manufacturing a semiconductor device comprising:

forming a columnar electrode comprising a barrier electrode portion on a semiconductor wafer wherein the base of the columnar electrode is parallel with the top surface of the columnar electrode over a span that extends from a first to a second sidewall of the columnar electrode;

flip-chip bonding a second semiconductor chip onto the semiconductor wafer;

forming a molding portion on the semiconductor wafer, the molding portion covering and molding the columnar electrode and the second semiconductor chip;

grinding or polishing the molding portion and the second semiconductor chip so that an upper face of the barrier electrode and an upper face of the semiconductor chip are exposed wherein the upper face of the barrier electrode and the upper face of the second semiconductor chip are coplanar; and

cutting the molding portion and the semiconductor wafer so that a first semiconductor chip is formed where the second semiconductor chip is flip-chip bonded and the columnar electrode is formed.

2. The method as claimed in claim 1 , further comprising grinding or polishing a lower face of the semiconductor wafer.

3. The method as claimed in claim 1 , wherein the columnar electrode is electrically coupled to the first semiconductor chip and the second semiconductor chip.

4. The method as claimed in claim 1 , wherein the step of forming the columnar electrode comprises the step of forming the columnar electrode with an electrolytic plating method.

5. The method as claimed in claim 4 , wherein:

the step of forming the columnar electrode includes the step of forming a lower electrode and a barrier electrode on the semiconductor wafer with the electrolytic plating method; and

the step of grinding or polishing the molding portion includes the step of grinding or polishing the molding portion together with an upper portion of the barrier electrode.

6. The method as claimed in claim 5 , further comprising the step of forming a solder terminal on the barrier electrode.

7. The method as claimed in claim 4 , wherein the step of flip-chip bonding the second semiconductor chip is performed after the step of forming the columnar electrode.

8. The method as claimed in claim 1 , wherein the step of forming the columnar electrode comprises the step of forming the columnar electrode so as to be lower than the second semiconductor chip that is to be flip-chip bonded onto the semiconductor wafer.

9. The method as claimed in claim 1 , wherein the step of forming the molding portion includes the steps of:

forming a first resin portion so as to cover an area between an upper face of the semiconductor wafer and a lower face of the second semiconductor chip;

and forming a second resin portion on the first resin portion.

10. The method as claimed in claim 9 , wherein the step of forming the first resin portion includes the step of coating a liquid resin on the semiconductor wafer to form the first resin portion.

11. The method as claimed in claim 1 , further comprising the step of mounting the first semiconductor chip onto a mount portion.