What is claimed is:
1. A semiconductor device comprising:
electrode pads provided on a base; and
solder bumps formed on said electrode pads via a barrier metal film;
wherein an adhesion layer is formed between said electrode pads and said barrier metal film for increasing the adhesion therebetween.
2. A semiconductor device according to claim 1, wherein said electrode pads are made from Cu or an alloy containing Cu.
3. A semiconductor device according to claim 2, wherein said adhesion layer is made from at least one kind of metal selected from a group consisting of Al, Ti, Cr, Co, Ni, Mo, Ag, Ta, W and Au, or an alloy containing said at least one kind of metal.
4. A method of fabricating a semiconductor device in which solder bumps are formed on electrode pads provided on a base via a barrier metal film, said method comprising:
a first step of forming a passivation film in such a manner as to cover electrode pads; forming a resist film on the passivation film and patterning the resist film into a specific shape; and selectively etching the passivation film using the resist film as a mask to expose the electrode pads;
a second step of forming an adhesion layer over the entire surface of the base; and removing a first portion, located on the resist film, of the adhesion layer together with the resist film by a lift-off method, to allow only a second portion, located on the electrode pads, of the adhesion layer to remain; and
a third step of forming solder bumps on the second portion of the adhesion layer located on the electrode pads via a barrier metal film.
5. A method of fabricating a semiconductor device according to claim 4, wherein said second step comprises a step of forming the adhesion layer over the entire surface of the base by a sputtering method, a chemical vapor deposition method, or an electrolytic plating method.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A flexible printed circuit for electrically connecting a disk tray to a chassis of an optical disk drive, comprising:
a base layer;
a copper layer attached to the base layer by a first adhesive layer, having a plurality of separate electrical wires and a ground area;
a cover layer having a cutout area, wherein the copper layer is attached to the cover layer by a second adhesive layer and the ground area is corresponded to the cutout area; and
a third adhesive layer for attaching the cover layer to the chassis of the optical disk drive, wherein the third adhesive layer is electrically conductive and electrically connected to the ground area of the copper layer through the cutout area.
2. The flexible printed circuit of claim 1 is U-shaped including a first connecting portion, a second connecting portion, and a central portion.
3. The flexible printed circuit of claim 2, wherein a first connecting end is integrally formed with the first connecting portion for electrically connecting to the disk tray, and a second connecting end is integrally formed with the second connecting portion for electrically connecting to the chassis.
4. The flexible printed circuit of claim 1, wherein the cover layer and the base layer are made of dielectric material and are nor electrically conductive.
5. The flexible printed circuit of claim 1, wherein the optical disk drive is slim-type DVD-ROM.
6. The flexible printed circuit of claim 1, wherein the separate electrical wires are formed on a copper foil by etching, the ground area is protect from being etched.