A semiconductor device that comprises a substrate with a primary surface and a secondary surface opposite to the primary surface. The primary surface provides a semiconductor active device. The semiconductor device includes a base metal layer deposited on the secondary surface and within the substrate via in which a vacancy is formed, and an additional metal layer on the base metal layer, the additional metal layer having different wettability against a solder as compared to the base metal layer whereby the solder is contactable by the base metal layer and repelled by the additional metal layer. The semiconductor device is die-bonded on the assembly substrate by interposing the solder between the secondary surface and the assembly substrate. The base metal layer in a portion that excepts the substrate via and a periphery of the substrate via by partly removing the additional metal layer is in contact with the solder.

A semiconductor device that comprises a substrate with a primary surface and a secondary surface opposite to the primary surface. The primary surface provides a semiconductor active device. The semiconductor device includes a base metal layer deposited on the secondary surface and within the substrate via in which a vacancy is formed, and an additional metal layer on the base metal layer, the additional metal layer having different wettability against a solder as compared to the base metal layer whereby the solder is contactable by the base metal layer and repelled by the additional metal layer. The semiconductor device is die-bonded on the assembly substrate by interposing the solder between the secondary surface and the assembly substrate. The base metal layer in a portion that excepts the substrate via and a periphery of the substrate via by partly removing the additional metal layer is in contact with the solder.

A mounting structure is used, which includes: a semiconductor element including an element electrode; a metal member; and a sintered body configured to bond the semiconductor element and the metal member is used, in which the sintered body contains a first metal and a second metal solid-dissolved in the first metal, the second metal is a metal having a diffusion coefficient in the first metal larger than a self-diffusion coefficient of the first metal, and a content ratio of the second metal relative to a total mass of the first metal and the second metal in the sintered body is equal to or lower than a solid solution limit of the second metal to the first metal.

A mounting structure is used, which includes: a semiconductor element including an element electrode; a metal member; and a sintered body configured to bond the semiconductor element and the metal member is used, in which the sintered body contains a first metal and a second metal solid-dissolved in the first metal, the second metal is a metal having a diffusion coefficient in the first metal larger than a self-diffusion coefficient of the first metal, and a content ratio of the second metal relative to a total mass of the first metal and the second metal in the sintered body is equal to or lower than a solid solution limit of the second metal to the first metal.

Liquid metal thermal interface materials and their uses in electronics assembly are described. In one implementation, a semiconductor assembly includes: a semiconductor die; a heat exchanger; and a thermal interface material (TIM) alloy bonding the semiconductor die to the heat exchanger without using a separate metallization layer on a surface of the semiconductor die or a surface of the heat exchanger. The TIM alloy may be formed by placing a TIM material between the semiconductor die and the heat exchanger, the TIM material comprising a first liquid metal foam in touching relation with the surface of the semiconductor die, a second liquid metal foam in touching relation with the surface of the heat exchanger.

A semiconductor device manufacturing method includes a preparation step and a sinter bonding step. In the preparation step, a sinter-bonding work having a multilayer structure including a substrate, semiconductor chips, and sinter-bonding material layers is prepared. The semiconductor chips are disposed on, and will bond to, one side of the substrate. Each sinter-bonding material layer contains sinterable particles and is disposed between each semiconductor chip and the substrate. In the sinter bonding step, a cushioning sheet having a thickness of 5 to 5000 μm and a tensile elastic modulus of 2 to 150 MPa is placed on the sinter-bonding work, the resulting stack is held between a pair of pressing faces, and, in this state, the sinter-bonding work between the pressing faces undergoes a heating process while being pressurized in its lamination direction, to form a sintered layer from each sinter-bonding material layer.

A semiconductor device manufacturing method includes a preparation step and a sinter bonding step. In the preparation step, a sinter-bonding work having a multilayer structure including a substrate, semiconductor chips, and sinter-bonding material layers is prepared. The semiconductor chips are disposed on, and will bond to, one side of the substrate. Each sinter-bonding material layer contains sinterable particles and is disposed between each semiconductor chip and the substrate. In the sinter bonding step, a cushioning sheet having a thickness of 5 to 5000 μm and a tensile elastic modulus of 2 to 150 MPa is placed on the sinter-bonding work, the resulting stack is held between a pair of pressing faces, and, in this state, the sinter-bonding work between the pressing faces undergoes a heating process while being pressurized in its lamination direction, to form a sintered layer from each sinter-bonding material layer.

A dicing die attach film including a dicing film and a die attach film laminated on the dicing film, in which the die attach film has an arithmetic average roughness Ra1 of from 0.05 to 2.50 μm at a surface in contact with the dicing film, and a value of ratio of Ra1 to an arithmetic average roughness Ra2 at a surface that is of the die attach film and is opposite to the surface in contact with the dicing film is from 1.05 to 28.00.

A dicing die attach film including a dicing film and a die attach film laminated on the dicing film, in which the die attach film has an arithmetic average roughness Ra1 of from 0.05 to 2.50 μm at a surface in contact with the dicing film, and a value of ratio of Ra1 to an arithmetic average roughness Ra2 at a surface that is of the die attach film and is opposite to the surface in contact with the dicing film is from 1.05 to 28.00.

An electronic device includes a first part, and a circuit plate including a circuit substrate, a plating film made of a plating material and being disposed on a front surface of the substrate. The plating film includes a first part region on which the first part is disposed via a first solder, and a liquid-repellent region extending along a periphery side of the first part region in a surface layer of the plating film, and having a liquid repellency greater than a liquid repellency of the plating film. The liquid-repellent region includes a resist region. The plating film includes a remaining portion between the liquid-repellent region and the front surface of the circuit substrate in a thickness direction of the plating film orthogonal to the front surface. The remaining portion is made of the plating material and is free of the oxidized plating material.