Semiconductor device and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-2016379946-A1
Application number	US-201414891319-A
Country	US
Kind code	A1
Filing date	Nov 13, 2014
Priority date	Nov 13, 2014
Publication date	Dec 29, 2016
Grant date	—

Abstract

A semiconductor device includes: a pad electrode 9 a formed in an uppermost layer of a plurality of wiring layers; a base insulating film 11 having an opening 11 a on the pad electrode 9 a ; a base metal film UM formed on the base insulating film 11 ; a redistribution line RM formed on the base metal film UM; and a cap metal film CM formed so as to cover an upper surface and a side surface of the redistribution line RM. In addition, in a region outside the redistribution line RM, the base metal film UM made of a material different from that of the redistribution line RM and the cap metal film CM made of a material different from the redistribution line RM are formed between the cap metal film CM formed on the side surface of the redistribution line RM and the base insulating film 11 , and the base metal film UM and the cap metal film CM are in direct contact with each other in the region outside the redistribution line RM.

First claim

What is claimed is:

1 . A semiconductor device comprising:
a semiconductor substrate: a plurality of wiring layers formed over the semiconductor substrate; a pad electrode formed in an uppermost layer of the plurality of wiring layers; an insulating film having an opening on the pad electrode; a base metal film formed on the insulating film; a redistribution line formed on the base metal film; and a cap metal film formed so as to cover an upper surface and a side surface of the redistribution line, wherein the base metal film is formed between the cap metal film formed on the side surface of the redistribution line and the insulating film in a region outside the redistribution line, the redistribution line and the base metal film are made of different materials, the redistribution line and the cap metal film are made of different materials, and the base metal film and the cap metal film are in direct contact with each other in the region outside the redistribution line.

2 . The semiconductor device according to claim 1 ,
wherein a sum of a thickness of the base metal film and a thickness of the cap metal film present in the region outside the redistribution line is larger than a thickness of the base metal film below the redistribution line.

3 . The semiconductor device according to claim 1 ,
wherein the cap metal film is made up of a laminated film including a first cap barrier film and a second cap barrier film, the first cap barrier film is a Ti film, the second cap barrier film is a Pd film, and the base metal film is a laminated film including a Ti film and a TiN film.

4 . The semiconductor device according to claim 1 ,
wherein the redistribution line contains Cu as a main component, the pad electrode contains Al as a main component, and a thickness of the redistribution line is larger than a thickness of the pad electrode.

5 . The semiconductor device according to claim 3 ,
wherein a copper wire is provided on the second cap metal film formed on the redistribution line.

6 . A manufacturing method of a semiconductor device comprising the steps of:
(a) preparing a semiconductor substrate having a plurality of wiring layers and a pad electrode formed in an uppermost layer of the plurality of wiring layers; (b) forming a first insulating film having a first opening on the pad electrode; (c) forming a base metal film electrically connected to the pad electrode through the first opening on the first insulating film; (d) forming a redistribution line electrically connected to the pad electrode through the base metal film on the base metal film; and (e) forming a cap metal film covering an upper surface and a side surface of the redistribution line, wherein the step (e) includes the steps of: (e-1) forming a cap metal material film on a main surface of the semiconductor substrate; and (e-2) etching the cap metal material film on the first insulating film, thereby forming the cap metal film, the etching in the step (e-2) is performed in a state where a part of the base metal film is present in a region outside the redistribution line, and after the step (e-2), the base metal film and the cap metal film are in direct contact with each other in the region outside the redistribution line.

7 . The manufacturing method of a semiconductor device according to claim 6 ,
wherein the redistribution line and the base metal film are made of different materials, and the redistribution line and the cap metal film are made of different materials.

8 . The manufacturing method of a semiconductor device according to claim 6 ,
wherein the cap metal material film is made up of a laminated film including a first cap barrier film, a second cap barrier film and a third cap barrier film, and the base metal film and the third cap barrier film contain the same material.

9 . The manufacturing method of a semiconductor device according to claim 6 ,
wherein the step (d) includes the steps of: (d-1) forming a seed film on the base metal film; (d-2) forming a resist pattern exposing apart of the seed film on the seed film; (d-3) forming the redistribution line by electroplating on the seed film exposed from the resist pattern; (d-4) removing the resist pattern; and (d-5) removing the seed film in the region outside the redistribution line, and in the step (e), the cap metal film is formed so as to cover a side surface of the seed film.

10 . The manufacturing method of a semiconductor device according to claim 6 ,
wherein the step (e-2) includes a step of performing wet etching of the base metal film.

11 . The manufacturing method of a semiconductor device according to claim 6 ,
wherein the redistribution line contains Cu as a main component, the pad electrode contains Al as a main component, and a thickness of the redistribution line is larger than a thickness of the pad electrode.

12 . The manufacturing method of a semiconductor device according to claim 6 ,
wherein a second insulating film is formed between the first insulating film and the pad electrode, and the second insulating film has a second opening smaller than the first opening in the first opening of the first insulating film.

13 . The manufacturing method of a semiconductor device according to claim 6 , further comprising the step of:
after the step (e), forming a third insulating film having a third opening on the cap metal film, wherein each of the first insulating film and the third insulating film includes a polyimide film.

14 . The manufacturing method of a semiconductor device according to claim 6 ,
wherein a copper wire is connected to the cap metal film on the redistribution line.

15 . The manufacturing method of a semiconductor device according to claim 6 , further comprising the step of:
after the step (d) and before the step (e), etching a part of the base metal film.

16 . A manufacturing method of a semiconductor device comprising the steps of:
(a) preparing a semiconductor substrate; (b) forming an insulating film on the semiconductor substrate; (c) forming a base metal film on the insulating film; (d) forming a redistribution line on the base metal film; (e) sequentially forming a first cap barrier film, a second cap barrier film and a third cap barrier film so as to cover an upper surface and a side surface of the redistribution line; (f) patterning the third cap barrier film formed on the insulating film with using a resist mask, while leaving the third cap barrier film on the upper surface and the side surface of the redistribution line; (g) removing the resist mask; (h) etching the second cap barrier film formed on the insulating film with using the patterned third cap barrier film as a mask; and (i) etching the third cap barrier film on the upper surface and the side surface of the redistribution line and etching the first cap barrier film and the base metal film on the insulating film.

17 . The manufacturing method of a semiconductor device according to claim 16 ,
wherein, after the step (i), the base metal film and the first cap barrier film are present in a region outside the redistribution line and on the insulating film, and a sum of a thickness of the base metal film and a thickness of the first cap barrier film present in the region outside the redistribution line is larger than a thickness of the base metal film below the redistribution line.

18 . The manufacturing method of a semiconductor device according to claim 16 ,
wherein the first, second and third

Assignees

• Renesas Electronics Corp

Inventors

• Maekawa Kazuyoshi
• Kawano Yuichi

Classifications

• H10W72/522

  Multilayered bond wires, e.g. having a coating concentric around a core · CPC title

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title

• H10W70/656

  Fan-in layouts · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title