Semiconductor integrated circuit device

Abstract

In semiconductor integrated circuit devices for vehicle use, an aluminum pad on a semiconductor chip and an external device are coupled to each other by wire bonding using a gold wire for the convenience of mounting. Such a semiconductor integrated circuit device, however, causes a connection failure due to the interaction between aluminum and gold in use for a long time at a relatively high temperature (about 150 degrees C.). A semiconductor integrated circuit device can include a semiconductor chip as a part of the device, an electrolytic gold plated surface film (gold-based metal plated film) provided over an aluminum-based bonding pad on a semiconductor chip via a barrier metal film, and a gold bonding wire (gold-based bonding wire) for interconnection between the plated surface film and an external lead provided over a wiring board (wiring substrate).

1 - 20 . (canceled) 
     
     
         21 . A semiconductor device, comprising:
 (a) an aluminium-based or a copper-based pad electrode provided over a device surface of a semiconductor chip;   (b) an insulating film formed over the device surface of the semiconductor chip and in which an opening is formed such that a part of the pad electrode is exposed from the opening;   (c) a barrier metal film provided over the part of the pad electrode exposed from the opening of the insulating film and a part thereof being contacted with a top surface of the insulating film;   (d) a surface metal film provided over the barrier metal film and including gold as a principal component, a film thickness of the surface metal film being greater than a film thickness of the barrier metal film; and   (e) a bonding ball bonded to the surface metal film and including gold or copper as a principal component,   wherein, in one cross-sectional view perpendicular to the device surface, a width of the surface metal film is greater than a width of the opening of the insulating film.   
     
     
         22 . The semiconductor device according to  claim 21 ,
 wherein, in the one cross-section view, a width of the barrier metal film is greater than a width of the opening of the insulating film.   
     
     
         23 . The semiconductor device according to  claim 22 ,
 wherein, in the one cross-section view, the width of the surface metal film and the width of the barrier metal film are the same.   
     
     
         24 . The semiconductor device according to  claim 23 ,
 wherein the part of the barrier metal film is contacted with a portion of the top surface of the insulating film around the opening in the top surface of the insulating film.   
     
     
         25 . The semiconductor device according to  claim 21 ,
 wherein a seed metal film is formed between the barrier metal film and the surface metal film.   
     
     
         26 . The semiconductor device according to  claim 25 ,
 wherein, in the one cross-section view, widths of the barrier metal film, the seed metal film, and the surface metal film are the same.   
     
     
         27 . The semiconductor device according to  claim 25 ,
 wherein the seed metal film includes palladium as a principal component.   
     
     
         28 . The semiconductor device according to  claim 25 ,
 wherein the seed metal film includes one selected from the group consisting of copper, gold, nickel, platinum, rhodium, molybdenum, tungsten, chrome, and tantalum as a principal component.   
     
     
         29 . The semiconductor device according to  claim 21 ,
 wherein, in another cross-section view perpendicular to the device surface, a width of the surface metal film is greater than a width of the pad electrode.   
     
     
         30 . The semiconductor device according to  claim 21 ,
 wherein the opening of the insulating film over the pad electrode is located within the surface metal film in plan view.   
     
     
         31 . The semiconductor device according to  claim 21 ,
 wherein the surface metal film is formed by electrolytic plating or sputtering.   
     
     
         32 . The semiconductor device according to  claim 21 ,
 wherein the surface metal film is formed by nonelectrolytic plating.   
     
     
         33 . The semiconductor device according to  claim 21 ,
 wherein a center of the bonding ball is set over a top surface of the surface metal film.   
     
     
         34 . The semiconductor device according to  claim 21 ,
 wherein the bonding ball is a part of a bonding wire.   
     
     
         35 . The semiconductor device according to  claim 21 ,
 wherein the barrier metal film includes titanium as a principal component.   
     
     
         36 . The semiconductor device according to  claim 21 ,
 wherein the barrier metal film includes one selected from the group consisting of titanium, chrome, titanium nitride, and tungsten nitride as a principal component.   
     
     
         37 . The semiconductor device according to  claim 21 ,
 wherein the pad electrode has a square shape in a plan view.   
     
     
         38 . The semiconductor device according to  claim 21 ,
 wherein the pad electrode has a rectangular shape in a plan view.   
     
     
         39 . A semiconductor device, comprising:
 (a) a first-metal based pad electrode provided over a device surface of a semiconductor chip;   (b) an insulating film formed over the device surface of the semiconductor chip and in which an opening is formed such that a part of the pad electrode is exposed from the opening;   (c) a barrier metal film provided over the pad electrode exposed from the opening of the insulating film and a part thereof being contacted with a top surface of the insulating film;   (d) a surface metal film provided over the barrier metal film and including gold as a principal component, a film thickness of the surface metal film being greater than a film thickness of the barrier metal film; and   (e) a bonding ball bonded to the surface metal film, and including a second metal as a principal component,   wherein, in one cross-sectional view perpendicular to the device surface, a width of the surface metal film is greater than a width of the opening of the insulating film.   
     
     
         40 . The semiconductor device according to  claim 39 ,
 wherein the first metal is aluminium and the second metal is copper.