Adhesive for circuit connection, circuit connection method using the same, and circuit connected structure

Abstract

There are provided an adhesive for connecting a circuit to be interposed between substrates having circuit electrodes thereon opposed to each other and to electrically connect the circuit electrodes on the substrates opposed to each other to the pressurizing direction under pressure, wherein the adhesive contains a compound having an acid equivalent of 5 to 500 KOH mg/g, and an adhesive for connecting a circuit to be interposed between substrates having circuit electrodes opposed to each other and to electrically connect the electrodes on the substrate opposed to each other to the pressurizing direction under pressure, wherein the adhesive comprises a first adhesive layer and a second adhesive layer, and a glass transition temperature of the first adhesive layer after pressure connection is higher than the glass transition temperature of the second adhesive layer after pressure connection.

1 . An adhesive for connecting a circuit to be interposed between substrates having circuit electrodes thereon opposed to each other and to electrically connect the circuit electrodes on the substrates opposed to each other to the pressurizing direction under pressure, wherein said adhesive contains a compound having an acid equivalent of 5 to 500 KOH mg/g.  
   
   
       2 . The adhesive for connecting a circuit according to  claim 1 , wherein the compound having an acid equivalent of 5 to 500 KOH mg/g is a compound having at least one carboxyl group.  
   
   
       3 . The adhesive for connecting a circuit according to  claim 2 , wherein the adhesive further contains a radical polymerizable substance.  
   
   
       4 . The adhesive for connecting a circuit according to  claim 3 , wherein the adhesive further contains conductive particles.  
   
   
       5 . A circuit connecting structure which is a circuit connecting structure to be interposed between substrates having circuit electrodes opposed to each other and to electrically connect the electrodes on the substrate opposed to each other to the pressurizing direction under pressure, wherein the adhesive for connecting a circuit is the adhesive according to  claim 4 .  
   
   
       6 . An adhesive for connecting a circuit to be interposed between substrates having circuit electrodes opposed to each other and electrically connect the electrodes on the substrate opposed to each other in the pressurizing direction under pressure, wherein said adhesive comprises a first adhesive layer and a second adhesive layer in a thickness direction, and a glass transition temperature of the first adhesive layer after pressure connection is higher than the glass transition temperature of the second adhesive layer after pressure connection.  
   
   
       7 . The adhesive for connecting a circuit according to  claim 6 , wherein Tg of the first adhesive layer after connection is 50 to 200° C., Tg of the second adhesive layer after connection is 40 to 100° C., and Tg of the first adhesive layer is not lower than 5° C. of Tg of the second adhesive layer after connection.  
   
   
       8 . The adhesive for connecting a circuit according to  claim 7 , wherein conductive particles are contained in at least one of the first adhesive layer and the second adhesive layer.  
   
   
       9 . The adhesive for connecting a circuit according to  claim 8 , wherein a radical polymerizable substance is contained in at least one of the first adhesive layer and the second adhesive layer.  
   
   
       10 . The adhesive for connecting a circuit according to  claim 9 , wherein a ratio of the thicknesses of the first adhesive layer and the second adhesive layer is a thickness of the first adhesive layer/a thickness of the second adhesive layer=0.3 to 3.0.  
   
   
       11 . The adhesive for connecting a circuit according to  claim 10 , wherein a compound having an acid equivalent of 5 to 500 KOH mg/g is contained in at least one of the first adhesive layer and the second adhesive layer.  
   
   
       12 . The circuit connecting method which comprises interposing the adhesive for connecting a circuit according to  claim 11  between substrates having circuit electrodes opposed to each other and electrically connecting the electrodes in the pressurizing direction by pressurizing the substrates, wherein said adhesive comprises a first adhesive layer and a second adhesive layer, Tg of the first adhesive layer after pressure connection is higher than Tg of the second adhesive layer after pressure connection, and the first adhesive layer having a higher Tg is provided and connected to the substrate side having a higher modulus of elasticity among the substrates having circuit electrode opposed to each other.  
   
   
       13 . A connecting structure which comprises the adhesive for connecting a circuit according to  claim 11  being interposed between substrates having circuit electrodes opposed to each other and the electrodes being electrically connected in the pressurizing direction by pressurizing the substrates, wherein said adhesive comprises a first adhesive layer and a second adhesive layer, Tg of the first adhesive layer after pressure connection is higher than Tg of the second adhesive layer after pressure connection, and the first adhesive layer having a higher Tg is provided and connected to the substrate side having higher modulus of elasticity among the substrates having circuit electrode opposed to each other.  
   
   
       14 . The adhesive for connecting a circuit according to  claim 1 , wherein the adhesive further contains a radical polymerizable substance.  
   
   
       15 . The adhesive for connecting a circuit according to  claim 1 , wherein the adhesive further contains conductive particles.  
   
   
       16 . A circuit connecting structure which is a circuit connecting structure to be interposed between substrates having circuit electrodes opposed to each other and to electrically connect the electrodes on the substrates opposed to each other in the pressurizing direction under pressure, wherein the adhesive for connecting a circuit is the adhesive according to  claim 1 .  
   
   
       17 . The adhesive for connecting a circuit according to  claim 6 , wherein conductive particles are contained in at least one of the first adhesive layer and the second adhesive layer.  
   
   
       18 . The adhesive for connecting a circuit according to  claim 6 , wherein a radical polymerizable substance is contained in at least one of the first adhesive layer and the second adhesive layer.  
   
   
       19 . The adhesive for connecting a circuit according to  claim 10 , wherein a ratio of the thicknesses of the first adhesive layer and the second adhesive layer is a thickness of the first adhesive layer/a thickness of the second adhesive layer=0.3 to 3.0.  
   
   
       20 . The adhesive for connecting a circuit according to  claim 6 , wherein a compound having an acid equivalent of 5 to 500 KOH mg/g is contained in at least one of the first adhesive layer and the second adhesive layer.  
   
   
       21 . The circuit connecting method which comprises interposing the adhesive for connecting a circuit according to  claim 6  between substrates having circuit electrodes opposed to each other and electrically connecting the electrodes in the pressurizing direction by pressurizing the substrates, wherein said adhesive comprises a first adhesive layer and a second adhesive layer, Tg of the first adhesive layer after pressure connection is higher than Tg of the second adhesive layer after pressure connection, and the first adhesive layer having a higher Tg is provided and connected to the substrate side having a higher modulus of elasticity among the substrates having circuit electrodes opposed to each other.  
   
   
       22 . A connecting structure which comprises the adhesive for connecting a circuit according to  claim 6  being interposed between substrates having circuit electrodes opposed to each other and the electrodes being electrically connected in the pressurizing direction by pressurizing the substrates, wherein said adhesive comprises a first adhesive layer and a second adhesive layer, Tg of the first adhesive layer after pressure connection is higher than Tg of the second adhesive layer after pressure connection, and the first adhesive layer having a higher Tg is provided and connected to the substrate side having a higher modulus of elasticity among the substrates having circuit electrodes opposed to each other.