An element chip manufacturing method includes a preparation process of preparing a substrate which includes a first surface provided with a bump and a second surface and includes a plurality of element regions defined by dividing regions, a bump embedding process of adhering a protection tape having an adhesive layer to the first surface and embedding. The element chip manufacturing method includes a thinning process of grinding the second surface in a state where the protection tape is adhered to the first surface and thinning the substrate, after the bump embedding process, a mask forming process of forming a mask in the second surface and exposes the dividing regions, after the thinning process, a holding process of arranging the first surface to oppose a holding tape supported on a frame and holding the substrate on the holding tape.

An element chip manufacturing method includes a preparation process of preparing a substrate which includes a first surface provided with a bump and a second surface and includes a plurality of element regions defined by dividing regions, a bump embedding process of adhering a protection tape having an adhesive layer to the first surface and embedding. The element chip manufacturing method includes a thinning process of grinding the second surface in a state where the protection tape is adhered to the first surface and thinning the substrate, after the bump embedding process, a mask forming process of forming a mask in the second surface and exposes the dividing regions, after the thinning process, a holding process of arranging the first surface to oppose a holding tape supported on a frame and holding the substrate on the holding tape.

There is provided a connection structure of a circuit member including: a first circuit member having a first main surface provided with a first electrode; a second circuit member having a second main surface provided with a second electrode; and a joining portion which is interposed between the first main surface and the second main surface, in which the joining portion has a solder portion which electrically connects the first electrode and the second electrode to each other, in which the solder portion contains a bismuth-indium alloy, and in which an amount of bismuth contained in the bismuth-indium alloy exceeds 20% by mass and is equal to or less than 80% by mass.

There is provided a connection structure of a circuit member including: a first circuit member having a first main surface provided with a first electrode; a second circuit member having a second main surface provided with a second electrode; and a joining portion which is interposed between the first main surface and the second main surface, in which the joining portion has a solder portion which electrically connects the first electrode and the second electrode to each other, in which the solder portion contains a bismuth-indium alloy, and in which an amount of bismuth contained in the bismuth-indium alloy exceeds 20% by mass and is equal to or less than 80% by mass.

An anisotropic conductive film contains conductive particles and spacers. The spacers are arranged at a central part of the film in a width direction. The central part of the film in the width direction represents 20 to 80% of the overall width of the film. The height of the spacers in the thickness direction of the anisotropic conductive film is larger than 5 m and less than 75 m. Such an anisotropic conductive film has a layered structure having a first insulating adhesion layer and a second insulating adhesion layer, wherein the conductive particles are dispersed in the first insulating adhesion layer, and the spacers are regularly arranged on a surface of the first insulating adhesion layer on a side of the second insulating adhesion layer.

An anisotropic conductive film contains conductive particles and spacers. The spacers are arranged at a central part of the film in a width direction. The central part of the film in the width direction represents 20 to 80% of the overall width of the film. The height of the spacers in the thickness direction of the anisotropic conductive film is larger than 5 m and less than 75 m. Such an anisotropic conductive film has a layered structure having a first insulating adhesion layer and a second insulating adhesion layer, wherein the conductive particles are dispersed in the first insulating adhesion layer, and the spacers are regularly arranged on a surface of the first insulating adhesion layer on a side of the second insulating adhesion layer.

An anisotropic conductive film that can be produced in high productivity and can reduce a short circuit occurrence ratio has a first conductive particle layer in which conductive particles are dispersed at a predetermined depth in a film thickness direction, and a second conductive particle layer in which conductive particles are dispersed at a depth different from that in the first conductive particle layer. In the respective conductive particle layers, the closest distances between the adjacent conductive particles are 2 times or more the average particle diameters of the conductive particles.

An anisotropic conductive film that can be produced in high productivity and can reduce a short circuit occurrence ratio has a first conductive particle layer in which conductive particles are dispersed at a predetermined depth in a film thickness direction, and a second conductive particle layer in which conductive particles are dispersed at a depth different from that in the first conductive particle layer. In the respective conductive particle layers, the closest distances between the adjacent conductive particles are 2 times or more the average particle diameters of the conductive particles.