Integrated circuit device having pads structure formed thereon and method for forming the same

Abstract

The invention is to provide a structure of IC pad and its forming method. The structure is arranged in an insulation layer and is comprised of a lower electric-conduction layer, a compound layer structure and a pad layer. The lower electric-conduction layer is arranged at an appropriate position in the insulation layer and is connected to an electric potential. The compound layer structure is arranged on the insulation layer and is composed of at least one electric-conduction layer and at least one electric-conduction connecting layer, both are inter-overlapped to each other. The pad layer is arranged on the compound layer structure.

What is claimed is: 
     
       1. An integrated circuit (IC) device having a pad structure formed thereon, the IC device comprising:
 a) a substrate;   b) an insulation layer formed on the substrate;   c) a lower electric-conduction layer formed in the insulation layer;   d) a compound layer structure formed in the insulation layer;   e) a first pad layer formed on the insulation layer and coupled to the compound layer structure, wherein the first pad layer and the compound layer structure are spaced apart from the lower electric-conduction layer; and   f) a second pad layer formed on the insulation layer and coupled to the lower electric-conduction layer.   
     
     
       2. The IC device according to  claim 1 , wherein the compound layer structure comprises a first electric-conduction layer and a first connecting layer to couple the first electric-conduction layer to the first pad layer. 
     
     
       3. The IC device according to  claim 2 , wherein the first connecting layer comprises a plurality of via plugs. 
     
     
       4. The IC device according to  claim 2 , wherein the first electric-conduction layer is shaped like a webbed railing. 
     
     
       5. The IC device according to  claim 2 , wherein the area of the first electric-conduction layer is smaller than that of the first pad layer. 
     
     
       6. The IC device according to  claim 1 , wherein the first pad layer is shaped like a polygon. 
     
     
       7. The IC device according to  claim 1 , further comprising a passivation layer formed on the insulation layer to cover a part of the outer rim of at least one of the first and second pad layers. 
     
     
       8. The IC device according to  claim 1 , further comprising at least one second connecting layer for coupling the second pad layer to the lower electric-conduction layer. 
     
     
       9. The IC device according to  claim 8 , further comprising at least one second electric-conduction layer coupled between the second pad layer and the lower electric-conduction layer with the second connecting layer. 
     
     
       10. The IC device according to  claim 1 , wherein a noise from the substrate is kept away from the first pad layer by the lower electric-conduction layer. 
     
     
       11. An integrated circuit (IC) device having a pad structure formed thereon, the IC device comprising:
 a) a substrate;   b) an insulation layer formed on the substrate;   c) a lower electric-conduction layer formed in the insulation layer;   d) a compound layer structure formed in the insulation layer; and   e) a first pad layer formed on the insulation layer and coupled to the compound layer structure, wherein the first pad layer and the compound layer structure are spaced apart from the lower electric-conduction layer.   
     
     
       12. The IC device according to  claim 11 , wherein the compound layer structure comprises a first electric-conduction layer and a first connecting layer to couple the first electric-conduction layer to the first pad layer. 
     
     
       13. The IC device according to  claim 11 , further comprising a second pad layer formed on the insulation layer and coupled to the lower electric-conduction layer. 
     
     
       14. The IC device according to  claim 13 , further comprising at least one second connecting layer for coupling the second pad layer to the lower electric-conduction layer; and at least one second electric-conduction layer coupled between the second pad layer and the lower electric-conduction layer with the second connecting layer. 
     
     
       15. The IC device according to  claim 14 , wherein, the area of the first electric-conduction layer is smaller than that of the first pad layer. 
     
     
       16. The IC device according to  claim 11 , wherein the first pad layer is shaped like a polygon. 
     
     
       17. The IC device according to  claim 11 , further comprising a passivation layer formed on the insulation layer to cover a part of the outer rim of at least one of the first and second pad layers. 
     
     
       18. The IC device according to  claim 11 , wherein a noise from the substrate is kept away from the first pad layer by the lower electric-conduction layer. 
     
     
       19. A method for fabricating an IC device having a pad structure formed thereon, the method comprising:
 a) providing a substrate;   b) forming an insulation layer formed on the substrate;   c) forming a lower electric-conduction layer formed in the insulation layer, at least a part of the lower electric-conduction layer being covered by the insulation layer;   d) forming a compound layer structure formed in the insulation layer, the compound layer structure being spaced apart from and not connected to the lower electric-conduction layer; and   e) forming a first pad layer formed on the insulation layer, the first pad layer being coupled to the compound layer,   wherein in the forming a first pad layer step e) the first pad layer and the compound layer are spaced apart from the lower electric-conduction layer.   
     
     
       20. The method according to  claim 19 , wherein a noise from the substrate is kept away form the first pad layer by the lower electric-conduction layer. 
     
     
       21. The method according to  claim 19 , wherein the forming a compound layer structure step d) further comprises the steps of:
 forming at least one first electric-conduction layer on the insulation layer; and   forming at least one first connecting layer on the insulation layer, wherein the first connecting layer is to couple the first electric-conduction layer to the first pad layer.   
     
     
       22. The method according to  claim 21 , wherein the area of the first electric-conduction layer is smaller than that of the first pad layer. 
     
     
       23. An integrated circuit (IC) device having a pad structure formed thereon, the IC device comprising:
 a) a substrate;   b) an insulation layer formed on the substrate;   c) a plurality of electric-conduction layers formed in the insulation layer, including a lower electric-conduction layer, each electric-conduction layer having a thickness;   d) a plurality of connecting layers, each connecting layer having a thickness, the connection layers interposed between the electric-conduction layers, the plurality of connecting layers selectively coupling one or more of the electric-conduction layers;   e) a compound layer structure formed in the insulation layer;   f) a first pad layer formed on the insulation layer and coupled to the compound layer structure, wherein the first pad layer and the compound layer structure are spaced apart and above from the lower electric-conduction layer, wherein the compound layer structure and the lower electric-conduction layer are spaced apart by the thickness of at least one electric-conduction layer and the thickness of at least one connecting layer; and   g) a second pad layer formed on the insulation layer and coupled to the lower electric-conduction layer.   
     
     
       24. The IC device according to claim 23, wherein the compound layer structure comprises a first electric-conduction layer and a first connecting layer to couple the first electric-conduction layer to the first pad layer. 
     
     
       25. The IC device according to claim 24, wherein the first connecting layer comprises a plurality of via plugs. 
     
     
       26. The IC device according to claim 24, wherein the first electric-conduction layer is shaped like a webbed railing. 
     
     
       27. The IC device according to claim 24, wherein the area of the first electric-conduction layer is smaller than that of the first pad layer. 
     
     
       28. The IC device according to claim 23, wherein the first pad layer is shaped like a polygon. 
     
     
       29. The IC device according to claim 23, further comprising a passivation layer formed on the insulation layer to cover a part of the outer rim of at least one of the first and second pad layers. 
     
     
       30. The IC device according to claim 23, further comprising at least one second connecting layer for coupling the second pad layer to the lower electric-conduction layer. 
     
     
       31. The IC device according to claim 30, further comprising at least one second electric-conduction layer coupled between the second pad layer and the lower electric-conduction layer with the second connecting layer. 
     
     
       32. An integrated circuit (IC) device having a pad structure formed thereon, the IC device comprising:
 a) a substrate;   b) an insulation layer formed on the substrate;   c) a lower electric-conduction layer formed in the insulation layer;   d) a compound layer structure formed in the insulation layer;   e) a first pad layer formed on the insulation layer and coupled to the compound layer structure, wherein the first pad layer and the compound layer structure are spaced apart from the lower electric-conduction layer; and   f) a second pad layer formed on the insulation layer and coupled to the lower electric-conduction layer, wherein a noise from the substrate is kept away from the first pad layer by the lower electric-conduction layer.   
     
     
       33. An integrated circuit (IC) device having a pad structure formed thereon, the IC device comprising:
 a) a substrate;   b) an insulation layer formed on the substrate;   c) a lower electric-conduction layer formed in the insulation layer;   d) a compound layer structure formed in the insulation layer;   e) a first pad layer formed on the insulation layer and coupled to the compound layer structure, wherein the first pad layer and the compound layer structure are spaced apart from the lower electric-conduction layer; and   f) a second pad layer formed on the insulation layer and coupled to the lower electric-conduction layer.   
     
     
       34. The IC device according to claim 33, wherein the compound layer structure comprises a first electric-conduction layer and a first connecting layer to couple the first electric-conduction layer to the first pad layer. 
     
     
       35. The IC device according to claim 33, further comprising at least one second connecting layer for coupling the second pad layer to the lower electric-conduction layer; and at least one second electric-conduction layer coupled between the second pad layer and the lower electric-conduction layer with the second connecting layer. 
     
     
       36. The IC device according to claim 35, wherein, the area of the first electric-conduction layer is smaller than that of the first pad layer. 
     
     
       37. The IC device according to claim 33, wherein the first pad layer is shaped like a polygon. 
     
     
       38. The IC device according to claim 33, further comprising a passivation layer formed on the insulation layer to cover a part of the outer rim of at least one of the first and second pad layers.