Package structures
A package structure is provided. The package structure includes a leadframe including a first portion and a second portion. The first portion includes a first base part and a plurality of first extended parts connected to the first base part. The second portion includes a second base part and a plurality of second extended parts connected to the second base part. The first extended parts and the second extended parts are arranged in such a way that they alternate with each other. In the package structure, a chip is disposed on a part of the first extended parts of the first portion and the second extended parts of the second portion of the leadframe. The package structure further includes a plurality of protrusions, opposite to the chip, disposed on the first extended parts and the second extended parts.
1. A package structure, comprising:
a leadframe comprising a first portion and a second portion opposite to the first portion, wherein the first portion comprises a first base part and a plurality of first extended parts connected to the first base part, the second portion comprises a second base part and a plurality of second extended parts connected to the second base part, and the first extended parts and the second extended parts are arranged in such a way that they alternate with each other as seen in a plan view;
a chip disposed on a part of the first extended parts of the first portion and the second extended parts of the second portion of the leadframe; and
a plurality of protrusions, opposite to the chip, disposed on the first extended parts and the second extended parts, wherein each of the first extended parts and the second extended parts has at least one protrusion disposed thereon.
2. The package structure as claimed in claim 1 , wherein there is a first distance between the first extended part of the first portion and the second base part of the second portion.
3. The package structure as claimed in claim 2 , wherein there is a second distance between the first base part of the first portion and the second base part of the second portion.
4. The package structure as claimed in claim 3 , wherein the second distance is greater than or equal to three times the first distance.
5. The package structure as claimed in claim 1 , wherein the first extended part of the first portion and the second extended part of the second portion have a first thickness.
6. The package structure as claimed in claim 5 , wherein the first base part of the first portion and the second base part of the second portion have a second thickness.
7. The package structure as claimed in claim 6 , wherein the second thickness is greater than or equal to two times the first thickness.
8. The package structure as claimed in claim 7 , wherein a difference between the second thickness and the first thickness is greater than or equal to 100 μm.
9. The package structure as claimed in claim 6 , wherein the second thickness is in a range from 200 μm to 400 μm.
10. The package structure as claimed in claim 1 , wherein the first extended part of the first portion has a bottom portion connected to the first base part and a top portion towards the second base part of the second portion, and the first extended part has a width which decreases gradually from the bottom portion to the top portion of the first extended part.
11. The package structure as claimed in claim 1 , wherein the chip is disposed on a part of the first extended parts of the first portion and the second extended parts of the second portion via solder balls.
12. The package structure as claimed in claim 1 , wherein the chip is disposed on a part of the first extended parts of the first portion and the second extended parts of the second portion via copper pillars.
13. The package structure as claimed in claim 1 , wherein the chip is disposed on a part of the first extended parts of the first portion and the second extended parts of the second portion via solder paste, silver paste or a solder bar.
14. The package structure as claimed in claim 1 , further comprising an encapsulation material covering the chip and a part of the leadframe, exposing sidewalls and bottoms of the first base part of the first portion and the second base part of the second portion of the leadframe.
15. The package structure as claimed in claim 14 , wherein the protrusions are made of metal or an insulating material.
16. The package structure as claimed in claim 15 , wherein the protrusions, the first base part and the second base part are coplanar and exposed from the encapsulation material.
17. The package structure as claimed in claim 16 , further comprising an insulating material layer covering the protrusions, when the protrusions are made of metal.
18. The package structure as claimed in claim 15 , further comprising an insulating material layer covering the protrusions, when the protrusions are made of metal, wherein the protrusions and the insulating material layer are buried in the encapsulation material.
19. The package structure as claimed in claim 1 , wherein the first extended parts and the second extended parts have a first thickness, the first base part and the second base part have a second thickness, and the second thickness is the same as the first thickness.
20. The package structure as claimed in claim 1 , wherein one of the first extended parts and one of the protrusions are formed as one single piece, and one of the second extended parts and one of the protrusions are formed as one single piece.