Semiconductor device and manufacturing method thereof

Abstract

A semiconductor device is arranged such that a semiconductor chip having electrodes is flip chip mounted on printed substrate pads on a printed wiring substrate by a bump formed on each electrode. The semiconductor chip and the printed wiring substrate are fixed with a thermo-setting resin. A penetration hole is formed within an area where the printed substrate pad contacts each gold bump, and the gold bump has a joint section also on a side face of the penetration hole of the printed substrate pad. With this structure, the semiconductor device has a secure electrical connection between the bump and the metal pattern.

What is claimed is:  
     
         1 . A flip chip mounted semiconductor device comprising: 
 a semiconductor chip having a bump;    a substrate having a wiring pattern joined to said bump; and    said wiring pattern having a stepped section formed within an area joined to said bump,    wherein said bump also joins a side face of said stepped section of said wiring pattern.    
     
     
         2 . The semiconductor device of  claim 1 , wherein: 
 said side face of said stepped section is formed virtually parallel to a facing direction of said semiconductor chip and said substrate.    
     
     
         3 . The semiconductor device of  claim 1 , further comprising: 
 a resin for use in fixing said semiconductor chip and said substrate.    
     
     
         4 . The semiconductor device of  claim 1 , wherein: 
 said wiring pattern has an inner surface formed by a hole within said area joined to said bump; and    said stepped section is formed by said inner surface.    
     
     
         5 . The semiconductor device of  claim 4 , wherein: 
 said wiring pattern joined to said bump has a tip in a semicircular shape, and has an inner surface formed by a hole in its center.    
     
     
         6 . The semiconductor device of  claim 1 , wherein: 
 said wiring pattern has an outer surface formed virtually parallel to a facing direction of said semiconductor chip and said substrate, in a periphery of said area joined to said bump; and    said stepped section is formed by said outer surface.    
     
     
         7 . The semiconductor device of  claim 6 , wherein: 
 said wiring pattern has a tip protruding from said area joined to said bump; and    said wiring pattern is formed so as to penetrate through said bump.    
     
     
         8 . The semiconductor device of  claim 6 , wherein: 
 said area of said wiring pattern, joined to said bump is formed in a polygon shape.    
     
     
         9 . The semiconductor device of  claim 1 , wherein: 
 said area of said wiring pattern, joined to said bump is divided into a plurality of pieces; and    each of said plurality of pieces has said stepped section.    
     
     
         10 . The semiconductor device of  claim 1 , wherein: 
 said substrate further includes a land for a through hole;    said wiring pattern joined to said bump is formed by the land for said through hole; and    the side face of said stepped section is an inner surface of said through hole.    
     
     
         11 . The semiconductor device of  claim 1 , wherein: 
 said substrate further includes a land for a via hole;    said wiring pattern joined to said bump is formed by the land for said via hole; and    the side face of said stepped section is an inner surface of said via hole.    
     
     
         12 . A flip chip mounted semiconductor device comprising: 
 a semiconductor chip having a bump; and    a substrate having a wiring pattern joined to said bump,    wherein when said substrate is seen from a side of said semiconductor chip, a contact area between said bump and said wiring pattern is smaller than an area of said bump in a direction of said substrate.    
     
     
         13 . The semiconductor device of  claim 12  further comprising: 
 a resin for use in fixing said semiconductor chip and said substrate.  
 
     
     
         14 . The semiconductor device of  claim 12 , wherein: 
 said wiring pattern joined to said bump has a tip in a semicircular shape, and has an inner surface formed by a hole in its center.    
     
     
         15 . The semiconductor device of  claim 12 , wherein: 
 said wiring pattern has a tip protruding from said area joined to said bump; and    said wiring pattern is formed so as to penetrate through said bump.    
     
     
         16 . The semiconductor device of  claim 12 , wherein: 
 said area of said wiring pattern, joined to said bump is formed in a polygon shape.    
     
     
         17 . The semiconductor device of  claim 12 , wherein: 
 said area joined to said bump of said wiring pattern is divided into a plurality of pieces.    
     
     
         18 . The semiconductor device of  claim 12 , wherein: 
 said substrate further includes a land for a through hole; and    said wiring pattern joined to said bump is formed by the land for said through hole.    
     
     
         19 . The semiconductor device of  claim 12 , wherein: 
 said substrate further includes a land for a via hole; and    said wiring pattern joined to said bump is formed by the land for said via hole.    
     
     
         20 . A method for manufacturing a semiconductor device comprising the step of conducting flip chip mounting by pressing a semiconductor chip having a bump onto a wiring pattern formed on a substrate, 
 said method for manufacturing a semiconductor device further comprising the steps of: 
 i) forming a stepped section on said wiring pattern; and  
 ii) joining said bump of said semiconductor chip also to a side face of the stepped section of said wiring pattern.  
   
     
     
         21 . The method for manufacturing a semiconductor device of  claim 20 , further comprising the step of: 
 iii) fixing said semiconductor chip and said substrate with a resin.    
     
     
         22 . The method for manufacturing the semiconductor device of  claim 20 , wherein said step ii) includes the steps of: 
 forming said bump on said semiconductor chip using a softer material than that of said wiring pattern; and    depressing said bump of said semiconductor chip onto a portion having a stepped section of said wiring pattern.    
     
     
         23 . The method for manufacturing the semiconductor device of  claim 21 , wherein: 
 in said step iii), an anisotropic conductive film is used as said resin; and    said step iii) includes the step of depressing said semiconductor chip onto the substrate with heat applied, via said anisotropic conductive film.    
     
     
         24 . The method for manufacturing the semiconductor device of  claim 21 , wherein: 
 said step ii) includes the step of joining said bump of said semiconductor chip and said wiring pattern formed on said substrate using ultrasonic vibrations; and    said step iii) is carried out after said step ii), whereby a spacing formed between said semiconductor chip and said substrate is sealed with said resin.    
     
     
         25 . A semiconductor device, wherein: 
 a semiconductor chip having electrodes is flip chip mounted on metal patterns formed on a substrate, by bumps, and said semiconductor chip and said substrate are fixed with a resin;    each metal pattern has a stepped section formed within an area joined to a corresponding bump; and    said bump also joints a side face of said metal pattern.    
     
     
         26 . A semiconductor device, wherein: 
 a semiconductor chip having electrodes is flip chip mounted on metal patterns formed on a substrate, by bumps, and said semiconductor chip and said substrate are fixed with a resin, and    wherein when said substrate is seen from a side of said semiconductor chip, a contact area between said bump and said metal pattern is smaller than an area of said bump in a direction of said substrate.    
     
     
         27 . A method for manufacturing a semiconductor device comprising the steps of: 
 conducting flip chip mounting by pressing a semiconductor chip having a bump on each electrode, onto a metal pattern formed on a substrate; and    fixing said semiconductor chip and said substrate with a resin,    the method for manufacturing a semiconductor device further comprising the steps of: 
 forming a stepped section on said metal pattern within an area joined to each bump; and  
 joining said bump also to a side face of the stepped section of said metal pattern.  
   
     
     
         28 . The method for manufacturing a semiconductor device of  claim 27 , wherein: 
 a resin in the form of an anisotropic conductive film is used as said resin for fixing said semiconductor chip and said substrate; and    said semiconductor chip having said bump on each electrode is pressed onto said substrate with heat applied, via said resin in the form of an anisotropic conductive film.    
     
     
         29 . The method for manufacturing the semiconductor device of  claim 27 , comprising the steps of: 
 i) joining said bump on said semiconductor chip and said metal pattern formed on said substrate using ultrasonic vibrations; and    ii) sealing a spacing formed between said semiconductor chip and said substrate with said resin after carrying out said step i).    
     
     
         30 . A flip chip mounted semiconductor device comprising: 
 a semiconductor chip having a bump; and    a substrate having a wiring pattern joined to said bump,    wherein said bump covers at least a part of a side face of said wiring pattern.