Metal particles-dispersed composition and flip chip mounting process and bump-forming process using the same

Abstract

A flip chip mounting process wherein a semiconductor chip and a circuit substrate are electrically interconnected. The process includes the steps of preparing a semiconductor chip on which a first plurality of electrodes are formed and a circuit substrate on which a second plurality of electrodes are formed; supplying a composition onto a surface of the circuit substrate, such surface being provided with second plurality of electrodes; bringing the semiconductor chip into contact with a surface of said composition such that the first plurality of electrodes are opposed to the second plurality of electrodes; and heating the circuit substrate, and thereby electrical connections including a metal component constituting the metal particles dispersed in the composition are formed between the first plurality of electrodes and the second plurality of electrodes. Also, a thermoset resin layer is formed between the semiconductor chip and the circuit substrate.

1 . A composition comprising a first component, a second component, metal particles and a convection additive wherein
 said metal particles are dispersed in said second component, and said convection additive is contained in said second component;   said first component is contained in an interior of at least one of said metal particles, wherein said metal particles melt upon heating so that said first component comes in contact with said second component to form a thermoset resin; and   said convection additive is capable of generating a gas upon heating.   
     
     
         2 . The composition according to  claim 1 , wherein said first component is a curing agent or a curing promoter used for forming said thermoset resin, whereas said second component is a base resin used for forming said thermoset resin. 
     
     
         3 . The composition according to  claim 2 , wherein
 said curing agent is at least one material selected from the group consisting of aliphatic amine, aromatic amine, aliphatic acid anhydride, cycloaliphatic acid anhydride, organic peroxide and polybasic acid; and   said base resin is at least one material selected from the group consisting of epoxy resin, unsaturated polyester resin, alkyd resin, polybutadiene resin, polyimide resin, polyamide resin and cyanate resin.   
     
     
         4 . The composition according to  claim 1 , wherein a metal component constituting said metal particles is at least one alloy selected from the group consisting of Sn—Pb alloy, Sn—Ag alloy, Sn—Ag—Cu alloy, Sn—Bi—Ag—In alloy, Sn—Bi—Zn alloy, Sn—Bi—Ag—Cu alloy, Sn—Zn alloy and Sn—Sb alloy. 
     
     
         5 . The composition according to  claim 1 , wherein said convection additive is at least one material selected from the group consisting of xylene, isobutyl alcohol, isopentyl alcohol, butyl acetate, tetrachlorethylene, methyl isobutyl ketone, ethyl carbitol, butyl carbitol, ethylene glycol, aluminum hydroxide, dawsonite, ammonium metaborate, barium metaborate and sodium hydrogen carbonate. 
     
     
         6 . The composition according to  claim 1 , wherein said gas provides a convection effect in said composition. 
     
     
         7 . The composition according to  claim 1 , wherein said composition is in paste form or in sheet form. 
     
     
         8 . The composition according to  claim 1 , wherein a content of a metal component constituting said metal particles ranges from 0.5 to 30% by volume with respect to said composition. 
     
     
         9 . The composition according to  claim 1 , wherein a melting point of a metal component constituting said metal particles is between a curing reaction-initiating temperature and a peak temperature of the curing reaction with respect to a mixture of said first component and said second component. 
     
     
         10 . The composition according to  claim 1 , wherein
 a boiling point of said convection additive is between a curing reaction-initiating temperature and a peak temperature of the curing reaction with respect to a mixture of said first component and said second component, or   said convection additive is decomposed to generate a gas under a temperature condition between a curing reaction-initiating temperature and a peak temperature of the curing reaction.