Semiconductor device having grooves to relieve stress between external electrodes and conductive patterns
A semiconductor device including a semiconductor chip having an electric circuit on a surface thereof, and an electrode pad formed on the surface of the semiconductor chip and which is electrically connected to the electric circuit. A conductive pattern is electrically connected to the pad, and a sealing resin covers the electric circuit and the conductive pattern. A part of the conductive pattern is exposed from the sealing resin, and a plurality of grooves are formed on the part of the conductive pattern. The plurality of grooves are disposed apart from each other and along a direction of stress of the expanding semiconductor chip. An external electrode is electrically connected to the conductive pattern. Stress of the external electrodes is thus relieved and as a result, reliability of the semiconductor device can be improved, because deterioration of the connecting quality can be prevented.
1. A semiconductor device, comprising:
a semiconductor chip having a surface, and expanding in a first direction when thermal stress is applied to said semiconductor chip;
an electric circuit formed on the surface of said semiconductor chip;
an electrode pad formed on the surface of said semiconductor chip and connected to said electric circuit;
a conductive pattern electrically connected to said pad;
a sealing resin covering said electric circuit and said conductive pattern so as to expose a part of said conductive pattern;
a plurality of grooves formed on the part of said conductive pattern and spaced apart from each other along a direction parallel to the first direction; and
an external electrode formed on the part of said conductive pattern.
2. The semiconductor device according to claim 1 , wherein each of said grooves is a line-shaped groove extending in a direction perpendicular to the first direction.
3. The semiconductor device according to claim 1 , wherein each of said grooves is a ring-shaped groove.
4. The semiconductor device according to claim 3 , wherein said grooves are concentric circles.
5. The semiconductor device according to claim 1 , wherein said external electrode is a solder ball.
6. The semiconductor device according to claim 5 , wherein said solder ball is made of a lead-free material.
7. A semiconductor device, comprising:
a semiconductor chip having a surface, and expanding in a first direction when thermal stress is applied to said semiconductor chip;
an electric circuit formed on the surface of said semiconductor chip;
an electrode pad formed on the surface of said semiconductor chip and electrically connected to said electric circuit;
an insulated resin post provided on the surface of said semiconductor chip and disposed adjacent to said electrode pad;
a conductive pattern extending on top of said insulated resin post from said electrode pad and electrically connected said electrode pad;
a sealing resin covering said electric circuit and said conductive pattern so as to expose a part of said conductive pattern on the top of said insulated resin post;
a plurality of grooves formed on the top of said insulated resin post and spaced apart from each other along a direction parallel to the first direction; and
an external electrode electrically connected to said conductive pattern.
8. The semiconductor device according to claim 7 , wherein each of said grooves is a line-shaped groove extending in a direction perpendicular to the first direction.
9. The semiconductor device according to claim 7 , wherein each of said grooves is a ring-shaped groove.
10. The semiconductor device according to claim 9 , wherein said grooves are concentric circles.
11. The semiconductor device according to claim 7 , wherein said external electrode is a solder ball.
12. The semiconductor device according to claim 11 , wherein said solder ball is made of a lead-free material.
13. The semiconductor device according to claim 7 , wherein a depth of said grooves is substantially equal to a half of a thickness of said conductive pattern.
14. The semiconductor device according to claim 7 , wherein said insulated resin post is made of heat-resistant resin.
15. The semiconductor device according to claim 14 , further comprising:
a water-resistant layer formed between the surface of said semiconductor chip and a bottom of said insulated resin post.
16. The semiconductor device according to claim 7 , wherein said insulated resin post is mesa-shaped.
17. A semiconductor device, comprising:
a semiconductor chip having a surface, and expanding in a first direction when thermal stress is applied to said semiconductor chip;
an electric circuit formed on the surface of said semiconductor chip;
an electrode pad formed on the surface of said semiconductor chip and electrically connected to said electric circuit;
an insulating layer covering said electric circuit and a part of said electrode pad;
a conductive pattern extending on said insulating layer from said electrode pad and electrically connected to said electrode pad;
a conductive post provided on a surface of said conductive pattern and electrically connected to said conductive pattern;
a sealing resin covering said electric circuit and said conductive pattern so as to expose a top of said conductive post;
a plurality of grooves formed on the top of said conductive post and spaced apart from each other along a direction parallel to the first direction; and
an external electrode formed on the top of said conductive post and electrically connected to said conductive post.
18. The semiconductor device according to claim 17 , wherein each of said grooves is a groove extending in a direction perpendicular to the first direction.
19. The semiconductor device according to claim 17 , wherein each of said grooves is a ring-shaped groove.
20. The semiconductor device according to claim 19 , wherein said grooves are concentric circles.
21. The semiconductor device according to claim 17 , wherein said external electrode is a solder ball.
22. The semiconductor device according to claim 21 , wherein said solder ball is made of a lead-free material.
23. The semiconductor device according to claim 17 , wherein said conductive pattern and said conductive post are made of copper.
24. The semiconductor device according to claim 1 , wherein each of said grooves is an oval-shaped groove.
25. The semiconductor device according to claim 24 , wherein said grooves are concentric ovals.
26. The semiconductor device according to claim 7 , wherein each of said grooves is an oval-shaped groove.
27. The semiconductor device according to claim 26 , wherein said grooves are concentric ovals.
28. The semiconductor device according to claim 17 , wherein each of said grooves is an oval-shaped groove.
29. The semiconductor device according to claim 28 , wherein said grooves are concentric ovals.