An anisotropic conductive film has a three-layer structure in which a first connection layer is sandwiched between a second connection layer and a third connection layer that each are formed mainly of an insulating resin. The first connection layer has a structure in which conductive particles are arranged in a single layer in the plane direction of an insulating resin layer on a side of the second connection layer, and the thickness of the insulating resin layer in central regions between adjacent ones of the conductive particles is smaller than that of the insulating resin layer in regions in proximity to the conductive particles.

A method is disclosed herein. The method includes dicing a wafer and applying a mask. The method includes spraying die bond material, at a first temperature, to a surface of the wafer and cooling the die bond material at a second temperature to at least partially solidify the die bond material. The method also includes removing the mask from the wafer through the die bond material. After the removing of the mask, the method includes curing the die bond material to form a die attach film layer on the wafer.

An anisotropic conductive film has a three-layer structure in which a first connection layer is sandwiched between a second connection layer and a third connection layer that each are formed mainly of an insulating resin. The first connection layer has a structure in which conductive particles are arranged in a single layer in the plane direction of an insulating resin layer on a side of the second connection layer, and the thickness of the insulating resin layer in central regions between adjacent ones of the conductive particles is smaller than that of the insulating resin layer in regions in proximity to the conductive particles.

An anisotropic conductive film has a three-layer structure in which a first connection layer is sandwiched between a second connection layer and a third connection layer that each are formed mainly of an insulating resin. The first connection layer has a structure in which conductive particles are arranged in a single layer in the plane direction of an insulating resin layer on a side of the second connection layer, and the thickness of the insulating resin layer in central regions between adjacent ones of the conductive particles is smaller than that of the insulating resin layer in regions in proximity to the conductive particles.

Anisotropic conductive film produced that a light-transmitting transfer die having openings with conductive particles disposed therein is prepared, and photopolymerizable insulating resin squeezed into openings to transfer conductive particles onto the surface of the photopolymerizable insulating resin layer, first connection layer is formed which has a structure in which conductive particles are arranged in a single layer in a plane direction of photopolymerizable insulating resin layer and the thickness of photopolymerizable insulating resin layer in central regions between adjacent ones of the conductive particles is smaller than thickness of photopolymerizable insulating resin layer in regions in proximity to conductive particles; first connection layer is irradiated with ultraviolet rays through light-transmitting transfer die; release film is removed from first connection layer; second connection layer is formed on the surface of first connection layer opposite to light-transmitting transfer die; and third connection layer is formed on the surface of first connection layer.

An anisotropic conductive film includes a conductive particle array layer in which a plurality of conductive particles are arrayed in a prescribed manner and held in an insulating resin layer. The anisotropic conductive film has a direction in which a thickness distribution, around the individual conductive particle, of the insulating resin layer holding the array of the conductive particles is asymmetric with respect to the conductive particle. The direction in which the thickness distribution is asymmetric is aligned in the same direction in the plurality of conductive particles. When an electronic component is mounted using this anisotropic conductive film, short circuits and conductive failure can be reduced.

Provided is an anisotropic conductive film manufacturing method capable of reducing manufacturing costs. Also provided is an anisotropic conductive film capable of suppressing the occurrence of conduction defects. The anisotropic conductive film manufacturing method includes: a holding step of supplying conductive particles having a plurality of particle diameters on a member having a plurality of opening parts, and holding the conductive particles in the opening parts; and a transfer step of transferring the conductive particles held in the opening parts to an adhesive film. In the particle diameter distribution graph (X-axis: particle diameter (μm), Y-axis: number of particles) of the conductive particles held in the opening parts, the shape of the graph is such that the slope is substantially infinite in a range at or above a maximum peak particle diameter.

The present disclosure is directed to a lead frame including a die pad with cavities, and methods for attaching a semiconductor die to the lead frame. The cavities allow for additional adhesive to be formed on the die pad at the corners of the semiconductor die, and prevent the additional adhesive from overflowing on to active areas of the semiconductor die.

The present disclosure is directed to a lead frame including a die pad with cavities, and methods for attaching a semiconductor die to the lead frame. The cavities allow for additional adhesive to be formed on the die pad at the corners of the semiconductor die, and prevent the additional adhesive from overflowing on to active areas of the semiconductor die.

An anisotropic conductive film manufacturing method capable of reducing manufacturing costs. Also, an anisotropic conductive film capable of suppressing the occurrence of conduction defects. The anisotropic conductive film manufacturing method includes: a holding step of supplying conductive particles having a plurality of particle diameters on a member having a plurality of opening parts, and holding the conductive particles in the opening parts; and a transfer step of transferring the conductive particles held in the opening parts to an adhesive film. In the particle diameter distribution graph (X-axis: particle diameter (μm), Y-axis: number of particles) of the conductive particles held in the opening parts, the shape of the graph is such that the slope is substantially infinite in a range at or above a maximum peak particle diameter.