Semiconductor device, dicing saw and method for manufacturing the semiconductor device

Abstract

A first interlayer insulating film and a second interlayer insulating film are formed on a semiconductor substrate and first Cu interconnections are formed in the first interlayer insulating film and second Cu interconnections are formed in the second interlayer insulating film. Pad electrodes are formed on the second Cu interconnections with a barrier metal interposed therebetween. The pad electrodes are made of AlCu containing Mg.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view for illustrating the principle of embodiments of the present invention.

FIG. 2 is a sectional view illustrating the structure of a semiconductor device according to a first embodiment of the present invention.

FIGS. 3A to 3D are sectional views illustrating the steps of a method for manufacturing the semiconductor device according to the first aspect of the present invention.

FIG. 4 is a schematic view illustrating a dicing step according to a second embodiment of the present invention.

FIG. 5 is a schematic view illustrating a dicing step according to a third embodiment of the present invention.

FIG. 6 is a schematic view illustrating a dicing step according to a fourth embodiment of the present invention.

FIG. 7 is a schematic view illustrating a dicing step according to a fifth embodiment of the present invention.

FIG. 8A is a view illustrating a conventional dicing technique and FIG. 8B is a sectional view illustrating a conventional interconnection structure.

Claims

1. A semiconductor device comprising: a semiconductor substrate;an insulating film formed on the semiconductor substrate;an interconnection formed on the insulating film and contains a first metal; andan electrode electrically connected to the interconnection and contains a second metal and an element having a higher ionization tendency than the second metal, whereinthe content of the element in the electrode is lower than the content of the second metal in the electrode.

2. The semiconductor device of claim 1, wherein the ionization tendency of the first metal is lower than that of the second metal.

3. The semiconductor device of claim 1, wherein the first metal is Cu, the second metal is Al and the element is Mg, Li, K or Ca.

4. A dicing saw for dicing a semiconductor substrate contains an element having a higher ionization tendency than Al.

5. The dicing saw of claim 4, wherein the element is Mg, Li, K or Ca.

6. A method for manufacturing a semiconductor device comprising the steps of: (a) forming an insulating film on a semiconductor substrate;(b) forming an interconnection containing a first metal on the insulating film; and(c) forming an electrode electrically connected to the interconnection and contains a second metal and an element having a higher ionization tendency than the second metal, whereinthe content of the element in the electrode is lower than the content of the second metal in the electrode.

7. The method of claim 6, wherein the ionization tendency of the first metal is higher than that of the second metal.

8. The method of claim 6, wherein the first metal is Cu, the second metal is Al and the element is Mg, Li, K or Ca.

9. A method for manufacturing a semiconductor device including the step of dicing a semiconductor substrate, wherein the semiconductor device includes an interconnection containing a first metal and an electrode electrically connected to the interconnection and contains a second metal having a higher ionization tendency than the first metal andthe dicing is carried out using a dicing saw containing an element having a higher ionization tendency than that of the second metal.

10. The method of claim 9, wherein the element is Mg, Li, K or Ca.

11. A method for manufacturing a semiconductor device including the step of dicing a semiconductor substrate, wherein the semiconductor device includes an interconnection containing a first metal and an electrode electrically connected to the interconnection and contains a second metal having a higher ionization tendency than the first metal andthe dicing is carried out while an ionization inhibitor for inhibiting the ionization of the second metal is supplied.

12. The method of claim 11, wherein the ionization inhibitor is an element having a higher ionization tendency than the second metal andthe dicing is carried out while liquid containing the element is supplied.

13. The method of claim 12, wherein the element is Mg, Li, K or Ca.

14. The method of claim 11, wherein the ionization inhibitor is a basic buffer solution andthe dicing is carried out while the basic buffer solution is supplied.

15. The method of claim 11, wherein the ionization inhibitor is hydrogen andthe dicing is carried out while liquid is supplied in an atmosphere where hydrogen partial pressure is higher than that in atmospheric air.