Connection structure and method of forming the same

1. A connection structure comprising:

a first passivation layer having an opening;

a first conductive pattern that penetrates the first passivation layer and protrudes upwardly from the first passivation layer;

a second passivation layer on the first passivation layer and covering the first conductive pattern;

a second conductive pattern on the second passivation layer and electrically connected to the first conductive pattern;

a third passivation layer on the second passivation layer and covering the second conductive pattern; and

an external terminal in the opening and electrically connected to the first conductive pattern,

wherein the first conductive pattern is thicker than the second conductive pattern,

wherein the second passivation layer is the thickest among the first to third passivation layers, and

wherein a head segment of the first conductive pattern which horizontally extends on the first passivation layer has a thickness larger than that of a redistribution layer segment, of the second conductive pattern, which horizontally extends on the second passivation layer.

2. The connection structure of claim 1 , wherein the first conductive pattern further comprises:

a tail segment that vertically penetrates the first passivation layer and has connection with the external terminal, wherein

the head segment of the first conductive pattern has connection with the second conductive pattern.

3. The connection structure of claim 1 , wherein the second conductive pattern includes:

the redistribution layer segment that horizontally extends on the second passivation layer; and

a via segment that vertically penetrates the second passivation layer and has connection with the first conductive pattern.

4. The connection structure of claim 3 , wherein

the redistribution layer segment of the second conductive pattern horizontally extends across the via segment of the second conductive pattern.

5. The connection structure of claim 1 , further comprising a third conductive pattern on the third passivation layer and electrically connected to the second conductive pattern.

6. The connection structure of claim 1 , further comprising an additional pattern on at least one of the first and second passivation layers.

7. The connection structure of claim 6 , wherein at least one of the first and second conductive patterns is provided in plural, and

wherein the additional pattern is formed between the plurality of first conductive patterns or between the plurality of second conductive patterns.

8. The connection structure of claim 6 , wherein the additional pattern is one of:

a dummy pattern electrically isolated on the at least one of the first and second passivation layers; and

a pattern either for electrical power delivery or for electrical ground.

9. The connection structure of claim 1 , further comprising a first seed pattern on a bottom surface of the first conductive pattern, the bottom surface of the first conductive pattern facing the external terminal.

10. The connection structure of claim 9 , wherein the first seed pattern is not provided at an interface between the first conductive pattern and the external terminal.

11. The connection structure of claim 1 , further comprising a second seed pattern on a bottom surface of the second conductive pattern, the bottom surface of the second conductive pattern facing the first conductive pattern.

12. A connection structure comprising:

a carrier substrate;

a first passivation layer, a second passivation layer, and a third passivation layer that are sequentially provided on the carrier substrate;

a first conductive pattern that penetrates the first passivation layer and protrudes upwardly from the first passivation layer; and

a second conductive pattern on the second passivation layer and electrically connected to the first conductive pattern,

wherein the first conductive pattern is thicker than the second conductive pattern,

wherein the second passivation layer is the thickest among the first to third passivation layers, and

wherein a head segment of the first conductive pattern which horizontally extends on the first passivation layer has a thickness larger than that of a redistribution layer segment, of the second conductive pattern, which horizontally extends on the second passivation layer.

13. The connection structure of claim 12 , wherein the first conductive pattern has a T shape comprising:

the head segment that horizontally extends on the first passivation layer; and

a tail segment that vertically penetrates the first passivation layer.

14. The connection structure of claim 12 , wherein the second conductive pattern is a redistribution layer which comprises:

the redistribution layer segment that horizontally extends on the second passivation layer; and

a via segment that vertically penetrates the second passivation layer.

15. The connection structure of claim 12 , further comprising a third conductive pattern on the third passivation layer and electrically connected to the second conductive pattern.

16. The connection structure of claim 15 , wherein the third conductive pattern is a connection pad which comprises:

a pad segment that horizontally extends on the second passivation layer; and

a via segment that vertically penetrates the second passivation layer.

17. The connection structure of claim 12 , further comprising an additional pattern on at least one of the first and second passivation layers,

wherein the additional pattern is one of:

a dummy pattern electrically isolated on the at least one of the first and second passivation layers; and

a conductive pattern either for electrical power delivery or for electrical ground.

18. The connection structure of claim 17 , wherein at least one of the first and second conductive patterns is provided in plural, and

wherein the additional pattern is formed between the plurality of first conductive patterns or between the plurality of second conductive patterns.

19. The connection structure of claim 12 , further comprising:

a first seed pattern on a bottom surface of the first conductive pattern, the bottom surface of the first conductive pattern facing the carrier substrate; and

a second seed pattern on a bottom surface of the second conductive pattern, the bottom surface of the second conductive pattern facing the first conductive pattern.

20. The connection structure of claim 12 , wherein

the carrier substrate has a lower passivation layer, and

the first passivation layer, the second passivation layer, and the third passivation layer are sequentially provided on the lower passivation layer.