Lead frame, semiconductor device, and method of manufacturing semiconductor device

1. A method of manufacturing a semiconductor device, comprising the steps of:

fixing an upper stage side semiconductor chip on a front surface of an inner lead part of a first lead frame and a lower stage side semiconductor chip on a rear surface of an inner lead part of a second lead frame;

overlapping at least a part of a frame body part of the first lead frame and a part of a frame body part of the second lead frame;

sealing with a mold resin the upper stage side semiconductor chip, the lower stage side semiconductor chip, the inner lead part of the first lead frame, and the inner lead part of the second lead frame; and

separating the semiconductor device by removing the frame body part of the first lead frame and the frame body part of the second lead frame, such that the first lead frame and the second lead frame are electrically isolated from each other.

2. The method of manufacturing a semiconductor device according to claim 1 , wherein the upper stage side semiconductor chip is flip-chip mounted on the first inner lead part and the lower stage side semiconductor chip is flip-chip mounted on the second inner lead part.

3. The method of manufacturing a semiconductor device according to claim 1 , wherein a distance from a top of the inner lead part to the frame body part of the first lead frame in a planar view and a distance from a top of the inner lead part to the frame body part of the second lead frame in the planar view are substantially the same.

4. The method of manufacturing a semiconductor device according to claim 1 , wherein a distance from a top of the inner lead part to the frame body part of the first lead frame in a planar view and a distance from a top of the inner lead part to the frame body part of the second lead frame in the planar view are different from each other.

5. The method of manufacturing a semiconductor device according to claim 1 , wherein the upper stage side semiconductor chip and the lower stage side semiconductor chip are different types of chips.

6. The method of manufacturing a semiconductor device according to claim 1 , wherein the upper stage side semiconductor chip and the lower stage side semiconductor chip are the same types of chips.

7. The method of manufacturing a semiconductor device according to claim 1 , wherein the upper stage side semiconductor chip and the lower stage side semiconductor chip have different sizes.

8. The method of manufacturing a semiconductor device according to claim 1 , wherein the step of overlapping at least parts of the frame body parts of the first and second lead frames includes interdigitating the inner lead parts of the first and second lead frames.

9. The method of manufacturing a semiconductor device according to claim 8 , wherein the inner lead parts of the first and second lead frames are provided in substantially the same plane.

10. The method of manufacturing a semiconductor device according to claim 1 , wherein the inner lead parts of the first and second lead frames are provided to overlap each other.

11. The method of manufacturing a semiconductor device according to claim 1 , wherein a geometry of the inner lead part of the first lead frame is different from a geometry of the inner lead part of the second lead frame.

12. The method of manufacturing a semiconductor device according to claim 1 , wherein the inner lead part of the first lead frame does not contact the inner lead part of the second lead frame.

13. A method of manufacturing a semiconductor device, comprising the steps of:

mounting an upper stage side semiconductor chip on a tip portion of an inner lead part of a first lead frame and a lower stage side semiconductor chip on a tip portion of an inner lead part of a second lead frame, respectively;

overlapping at least a part of a frame body part of the first lead frame and a part of a frame body part of the second lead frame so that the tip portion of the inner lead part of the first lead frame and the tip portion of the inner lead part of the second lead frame are sandwiched between the upper stage side semiconductor chip and the lower stage side semiconductor chip, a tip portion of the inner lead part of the first lead frame and a tip portion of the inner lead part of the second lead frame do not contact with each other, and the tip portion of the inner lead part of the first lead frame and the tip portion of the inner lead part of the second lead frame are provided in the same plane;

sealing with a mold resin the upper stage side semiconductor chip, the lower stage side semiconductor chip, the inner lead part of the first lead frame, and the inner lead part of the second lead frame; and

separating the semiconductor device by removing the frame body part of the first lead frame and the frame body part of the second lead frame.

14. The method of manufacturing a semiconductor device according to claim 13 , wherein the upper stage side semiconductor chip is flip-chip mounted on the tip portion of the inner lead part of the first lead frame and the lower stage side semiconductor chip is flip-chip mounted on the tip portion of the inner lead part of the second lead frame, respectively.

15. The method of manufacturing a semiconductor device according to claim 13 , wherein a distance from a top of the inner lead part to the frame body part of the first lead frame in a planar view and a distance from a top of the inner lead part to the frame body part of the second lead frame in the planar view are substantially the same.

16. The method of manufacturing a semiconductor device according to claim 13 , wherein a distance from a top of the inner lead part to the frame body part of the first lead frame in a planar view and a distance from a top of the inner lead part to the frame body part of the second lead frame in the planar view are different from each other.

17. The method of manufacturing a semiconductor device according to claim 13 , wherein the inner lead part of the first lead frame is pressed to form a rising part between the tip portion and an outer lead part thereof, the lower stage side semiconductor chip is mounted at a side that the rising part thereof is provided in a cross sectional view.

18. The method of manufacturing a semiconductor device according to claim 17 , wherein the first lead frame is set that the rising part is seemed to a depressed part when the lower stage side semiconductor chip is mounted on the tip portion of the inner lead part of the first lead frame.

19. The method of manufacturing a semiconductor device according to claim 18 , wherein the first lead frame that the lower stage side semiconductor chip is mounted is turned upside down before the overlapping at least a part of a frame body part of the first lead frame and a part of a frame body part of the second lead frame.

20. The method of manufacturing a semiconductor device according to claim 13 , wherein the inner lead part of the second lead frame is pressed to form a rising part between the tip portion and an outer lead part thereof, the upper stage side semiconductor chip is mounted at an opposite side from a side that the rising part thereof is provided in a cross sectional view.