There is provided a bonding paste capable of forming a uniform bonding layer by reducing occurrence of voids at edges even when a bonding area is large, and bonding method using the paste, and provides a metal paste for bonding containing at least metal nanoparticles (A) having a number average primary particle size of 10 to 100 nm, wherein a cumulative weight loss value (L.sub.100) when a temperature is raised from 40° C. to 100° C. is 75 or less, and a cumulative weight loss value (L.sub.150) when a temperature is raised from 40° C. to 150° C. is 90 or more, and a cumulative weight loss value (L.sub.200) when a temperature is raised from 40° C. to 200° C. is 98 or more, based on 100 cumulative weight loss value (L.sub.700) when the paste is heated from 40° C. to 700° C. at a heating rate of 3° C./min in a nitrogen atmosphere.

To reduce substrate warp occurring after connection an anisotropic conductive film is used. An anisotropic conductive film has: a first insulating adhesive layer; a second insulating adhesive layer; and a conductive particle-containing layer sandwiched by the first insulating adhesive layer and the second insulating adhesive layer and having conductive particles contained in an insulating adhesive, wherein air bubbles are contained between the conductive particle-containing layer and the first insulating adhesive layer, and, the conductive particle-containing layer, a portion thereof below the conductive particles and in contact with the second insulating adhesive layer has a lower degree of cure than other portions thereof.

To reduce substrate warp occurring after connection an anisotropic conductive film is used. An anisotropic conductive film has: a first insulating adhesive layer; a second insulating adhesive layer; and a conductive particle-containing layer sandwiched by the first insulating adhesive layer and the second insulating adhesive layer and having conductive particles contained in an insulating adhesive, wherein air bubbles are contained between the conductive particle-containing layer and the first insulating adhesive layer, and, the conductive particle-containing layer, a portion thereof below the conductive particles and in contact with the second insulating adhesive layer has a lower degree of cure than other portions thereof.

To reduce substrate warp occurring after connection an anisotropic conductive film is used. An anisotropic conductive film has: a first insulating adhesive layer; a second insulating adhesive layer; and a conductive particle-containing layer sandwiched by the first insulating adhesive layer and the second insulating adhesive layer and having conductive particles contained in an insulating adhesive, wherein air bubbles are contained between the conductive particle-containing layer and the first insulating adhesive layer, and, the conductive particle-containing layer, a portion thereof below the conductive particles and in contact with the second insulating adhesive layer has a lower degree of cure than other portions thereof.

To reduce substrate warp occurring after connection an anisotropic conductive film is used. An anisotropic conductive film has: a first insulating adhesive layer; a second insulating adhesive layer; and a conductive particle-containing layer sandwiched by the first insulating adhesive layer and the second insulating adhesive layer and having conductive particles contained in an insulating adhesive, wherein air bubbles are contained between the conductive particle-containing layer and the first insulating adhesive layer, and, the conductive particle-containing layer, a portion thereof below the conductive particles and in contact with the second insulating adhesive layer has a lower degree of cure than other portions thereof.

To reduce substrate warp occurring after connection an anisotropic conductive film is used. An anisotropic conductive film has: a first insulating adhesive layer; a second insulating adhesive layer; and a conductive particle-containing layer sandwiched by the first insulating adhesive layer and the second insulating adhesive layer and having conductive particles contained in an insulating adhesive, wherein air bubbles are contained between the conductive particle-containing layer and the first insulating adhesive layer, and, the conductive particle-containing layer, a portion thereof below the conductive particles and in contact with the second insulating adhesive layer has a lower degree of cure than other portions thereof.

To reduce substrate warp occurring after connection an anisotropic conductive film is used. An anisotropic conductive film has: a first insulating adhesive layer; a second insulating adhesive layer; and a conductive particle-containing layer sandwiched by the first insulating adhesive layer and the second insulating adhesive layer and having conductive particles contained in an insulating adhesive, wherein air bubbles are contained between the conductive particle-containing layer and the first insulating adhesive layer, and, the conductive particle-containing layer, a portion thereof below the conductive particles and in contact with the second insulating adhesive layer has a lower degree of cure than other portions thereof.