A technique for fabricating a bump structure is disclosed. A substrate that includes a set of pads formed on a surface thereof is prepared, in which the pads includes first conductive material. A metallic adhesion layer is coated on each pad. A bump base is formed on each pad by sintering conductive particles using a mold layer, in which the conductive particles includes second conductive material different from the first conductive material.

A technique for fabricating a bump structure is disclosed. A substrate that includes a set of pads formed on a surface thereof is prepared, in which the pads includes first conductive material. A metallic adhesion layer is coated on each pad. A bump base is formed on each pad by sintering conductive particles using a mold layer, in which the conductive particles includes second conductive material different from the first conductive material.

According to one aspect of the present invention, a lead-free solder alloy includes 2% by mass or more and 3.1% by mass or less of Ag, more than 0% by mass and 1% by mass or less of Cu, 1% by mass or more and 5% by mass or less of Sb, 3.1% by mass or more and 4.5% by mass or less of Bi, 0.01% by mass or more and 0.25% by mass or less of Ni, and Sn.

A chip interconnection structure, a chip and a chip interconnection method. The chip interconnection structure includes a first chip and at least one second chip, where a transfer surface of the first chip and a transfer surface of the second chip are disposed oppositely, at least one conductive component is further provided between the second chip and the first chip, each conductive component includes at least one conductive member, and the conductive member is connected between a pad of the second chip and a pad of the first chip. The chip interconnection structure can allow two or more than two chips to be interconnected and to communicate at a high speed.

A chip interconnection structure, a chip and a chip interconnection method. The chip interconnection structure includes a first chip and at least one second chip, where a transfer surface of the first chip and a transfer surface of the second chip are disposed oppositely, at least one conductive component is further provided between the second chip and the first chip, each conductive component includes at least one conductive member, and the conductive member is connected between a pad of the second chip and a pad of the first chip. The chip interconnection structure can allow two or more than two chips to be interconnected and to communicate at a high speed.

An electronic device includes a substrate having top side contact pads including metal pillars thereon or a laminate substrate having land pads with the pillars thereon. A solder including layer stack is on the pillars, the solder including layer stack having a bottom solder material layer including in physical contact with a top surface of the pillars, a metal material layer, and a capping solder material layer on the metal material layer. The metal material layer is primarily a copper layer or an intermetallic compound (IMC) layer including copper.

An electronic device includes a substrate having top side contact pads including metal pillars thereon or a laminate substrate having land pads with the pillars thereon. A solder including layer stack is on the pillars, the solder including layer stack having a bottom solder material layer including in physical contact with a top surface of the pillars, a metal material layer, and a capping solder material layer on the metal material layer. The metal material layer is primarily a copper layer or an intermetallic compound (IMC) layer including copper.

An integrated circuit die may be fabricating to have a plurality of contacts. A metal post may be formed on each of the plurality of contacts. A plurality of bumps may be formed on a plurality of contact regions of a leadframe or on the posts, in which the plurality of bumps are formed with a material that includes metal nanoparticles. The IC die may be attached to the leadframe by aligning the metal posts to the leadframe and sintering the metal nanoparticles in the plurality of bumps to form a sintered metal bond between each metal post and corresponding contact region of the leadframe.

A flux includes a rosin resin, an activator, a thixotropic agent, and a solvent. The solvent includes 30% by mass or more and 60% by mass or less monovalent alcohol with respect to a total mass amount of the flux. The monovalent alcohol has 18 or more and 24 or less of carbon atoms in one molecule.

A first electronic element is disclosed, which includes: a first substrate having a first surface; a first electrode pad disposed on the first surface, wherein the first electrode pad has a second surface away from the first substrate; and an insulating layer disposed on the first surface, wherein the insulating layer includes an opening, the opening is disposed correspondingly to the first electrode pad, and the opening overlaps the first electrode pad in a normal direction of the first surface, wherein the insulating layer has a third surface away from the first substrate, a distance between the third surface and the second surface in the normal direction of the first surface is defined as a first distance, and the first distance is greater than 0 m and less than or equal to 14 m. In addition, the disclosure further provides an electronic device including the first electronic element.