An apparatus for bonding die to a board includes a circuit board having a solderable layer and a plurality of die bonded to the circuit board using at least three respective layers. Each of the at least three respective layers includes an inner layer, a first alloy of material from an outer layer and the solderable layer of the circuit board, and a second alloy of material from the outer layer and the solderable layer of the circuit board. Melting temperatures of the first alloy and the second alloy are higher than reflow temperatures of the outer layer and the solderable layer of the circuit board.

A compound and method of use thereof consisting of an A-staged thermoplastic-polyimide (TPI) adhesive, a viscous uncured liquid of polyamic-acid polymer (PAA), the TPI precursor, synthesized and dissolved in a polar aprotic organic solvent, and including, as appropriate, combinations of particulate ceramic and/or metallic thermally conducting, electrically insulating, and thermally conducting, electrically conducting fillers for interface-bonding to create a robust joint between surfaces with conventional lamination processes that utilize relatively moderate temperatures and applied pressures.

A method of bonding a plurality of die having first and second metal layers on a die surface to a board, comprising placing a first die onto a board comprising one of a ceramic or substrate board or metal lead frame having a solderable surface and placing the first die and the board into a reflow oven. The method includes reflowing at a first reflow temperature for a first period until the first metal board layer and at least one of the first and second metal die layers of the first die form an alloy to adhere the first die to the board. The alloy has a melting temperature higher than the first reflow temperature. Accordingly, additional die may be added at a later time and reflowed to attach to the board without causing the bonding of the first die to the board to fail.

A semiconductor device may include: a first and a second semiconductor elements each including electrodes on both surfaces thereof; a first and a second metal plates which interpose the first semiconductor element, the metal plates respectively being bonded to the first semiconductor element via first soldered portions; and a third and a fourth metal plates which interpose the second semiconductor element, the metal plates respectively being bonded to the second semiconductor element via second soldered portions; wherein a first joint is provided at the first metal plate, a second joint is provided at the fourth metal plate, the joints are bonded via a third soldered portion, and a solidifying point of the first soldered portions is higher than a solidifying point of the third soldered portion, and a solidifying point of the second soldered portions is higher than the solidifying point of the third soldered portion.

The invention relates to a power module (1) comprising a substrate (2). an electrically conductive intermediate layer (3) which is arranged on the substrate (2) and which has a joining region (4) produced by means of sintering, and at least one power component (5) which is arranged on the intermediate layer (3) and the sintered joining region (4) and is connected thereto (in particular at the load connection of the power component (5)) and which has at least one connection point (6) (e.g. a control connection) connected to the intermediate layer (3), wherein the intermediate layer (3) has. in the region of the associated connection point (6). a solder region (7) produced by means of a solder preform and spaced and/or electrically insulated from the sintered joining region (4). The large active surface, which is subjected to high thermomechanical stress in the service life test. can therefore be connected via the sintered joining region (4), which ensures an especially long-lasting, reliable and resilient mechanical connection between the associated power component (5) and the substrate (2). At the associated connection point (6), e.g. the gate of a transistor, the thermomechanical stress is usually much less, which is why there in the intermediate layer (3) a solder preform can be used for producing the connection between the associated power component (5) and the substrate (2), such solder preforms being relatively cost-effectively obtainable. Furthermore. an electrical device (10) has at least one such power module (1). The joining region (4) produced by means of sintering can be formed by means of a sinter preform or by means of 3D printing. by means of a coating method or by means of screen printing/stencil printing. In the method for producing the power module (1). the intermediate layer (3) can be heated to the melting temperature of the solder if the melting temperature of the solder is higher than the sintering temperature or to the sintering temperature if the sintering temperature is higher than the melting temperature of the solder, and the layer thickness (9) of the sintering material for the joining region (4) produced by means of sintering can be larger or smaller than the layer thickness (9) of the solder for the associated solder region (7) if the sintering temperature is correspondingly lower or higher than the melting temperature of the solder. Alternatively. the melting temperature of the solder can be substantially t

A semiconductor device may include: a first and a second semiconductor elements each including electrodes on both surfaces thereof; a first and a second metal plates which interpose the first semiconductor element, the metal plates respectively being bonded to the first semiconductor element via first soldered portions; and a third and a fourth metal plates which interpose the second semiconductor element, the metal plates respectively being bonded to the second semiconductor element via second soldered portions; wherein a first joint is provided at the first metal plate, a second joint is provided at the fourth metal plate, the joints are bonded via a third soldered portion, and a solidifying point of the first soldered portions is higher than a solidifying point of the third soldered portion, and a solidifying point of the second soldered portions is higher than the solidifying point of the third soldered portion.

[Solving Means] A component includes a main body, a first layer, and a second layer. The main body includes a bottom surface. The first layer is provided on the bottom surface of the main body and includes a bottom surface. The second layer is bonded to a metal bonding material on a substrate to be provided physically integrally. The second layer has higher wettability with respect to the metal bonding material in a molten state than the first layer, and protrudes from the bottom surface side of the first layer such that at least a part of the bottom surface of the first layer is exposed on an entire outer circumference side of the second layer.

A compound and method of use thereof consisting of an A-staged thermoplastic-polyimide (TPI) adhesive, a viscous uncured liquid of polyamic-acid polymer (PAA), the TPI precursor, synthesized and dissolved in a polar aprotic organic solvent, and including, as appropriate, combinations of particulate ceramic and/or metallic thermally conducting, electrically insulating, and thermally conducting, electrically conducting fillers for interface-bonding to create a robust joint between surfaces with conventional lamination processes that utilize relatively moderate temperatures and applied pressures.

In a heat insulating load jig 11 of the present invention, a solder material 14 having a melting point or a solidus temperature in a range between a thermal resistance temperature of a semiconductor chip 13 and a temperature 100 C. below the thermal resistance temperature is interposed between a circuit board 12 and the semiconductor chip 13; a heat insulating body 17 is placed on an upper side of the semiconductor chip 13 in this state; a metal weight 16 is disposed on the heat insulating body 17; and load is applied to the semiconductor chip 13 while the solder material 14 is melted and solidified.

A solder paste including a metal component consisting of a first metal powder and a second metal powder having a melting point higher than that of the first metal, and a flux component. The first metal is Sn or an alloy containing Sn, the second metal is one of (1) a CuMn alloy in which a ratio of Mn to the second metal is 5 to 30% by weight and (2) a CuNi alloy in which a ratio of Ni to the second metal is 5 to 20% by weight, and a ratio of the second metal to the metal component is 36.9% by volume or greater.