Provided is a metal paste for joints, containing: metal particles; and linear or branched monovalent aliphatic alcohol having 1 to 20 carbon atoms, in which the metal particles include sub-micro copper particles having a volume average particle diameter of 0.12 m to 0.8 M.

The power semiconductor apparatus includes: a semiconductor device 401; a bonding layer on chip 416 disposed on an upper surface of the semiconductor device; and a metal lead 419 disposed on the upper surface of the semiconductor device and bonded to the bonding layer on chip, wherein the metal lead 420 has a three-laminated structure including: a second metal layer 420b having a CTE equal to or less than 510.sup.6/ C., for example; and a first metal layer 420a and a third metal layer 420c sandwiching the second metal layer and having a CTE equal to or greater than the CTE of the second metal layer. Provided is a power semiconductor apparatus capable of improving reliability thereof by reducing a thermal stress to a bonding layer between a semiconductor power device and a metal lead positioned on an upper surface thereof, and reducing a resistance of the metal lead.

The power semiconductor apparatus includes: a semiconductor device 401; a bonding layer on chip 416 disposed on an upper surface of the semiconductor device; and a metal lead 419 disposed on the upper surface of the semiconductor device and bonded to the bonding layer on chip, wherein the metal lead 420 has a three-laminated structure including: a second metal layer 420b having a CTE equal to or less than 510.sup.6/ C., for example; and a first metal layer 420a and a third metal layer 420c sandwiching the second metal layer and having a CTE equal to or greater than the CTE of the second metal layer. Provided is a power semiconductor apparatus capable of improving reliability thereof by reducing a thermal stress to a bonding layer between a semiconductor power device and a metal lead positioned on an upper surface thereof, and reducing a resistance of the metal lead.

The power semiconductor apparatus includes: a semiconductor device 401; a bonding layer on chip 416 disposed on an upper surface of the semiconductor device; and a metal lead 419 disposed on the upper surface of the semiconductor device and bonded to the bonding layer on chip, wherein the metal lead 420 has a three-laminated structure including: a second metal layer 420b having a CTE equal to or less than 510.sup.6/ C., for example; and a first metal layer 420a and a third metal layer 420c sandwiching the second metal layer and having a CTE equal to or greater than the CTE of the second metal layer. Provided is a power semiconductor apparatus capable of improving reliability thereof by reducing a thermal stress to a bonding layer between a semiconductor power device and a metal lead positioned on an upper surface thereof, and reducing a resistance of the metal lead.

The power semiconductor apparatus includes: a semiconductor device 401; a bonding layer on chip 416 disposed on an upper surface of the semiconductor device; and a metal lead 419 disposed on the upper surface of the semiconductor device and bonded to the bonding layer on chip, wherein the metal lead 420 has a three-laminated structure including: a second metal layer 420b having a CTE equal to or less than 510.sup.6/ C., for example; and a first metal layer 420a and a third metal layer 420c sandwiching the second metal layer and having a CTE equal to or greater than the CTE of the second metal layer. Provided is a power semiconductor apparatus capable of improving reliability thereof by reducing a thermal stress to a bonding layer between a semiconductor power device and a metal lead positioned on an upper surface thereof, and reducing a resistance of the metal lead.

A power semiconductor device includes a Si chip providing a Si switch and a wide bandgap material chip providing a wide bandgap material switch, wherein the Si switch and the wide bandgap material switch are electrically connected in parallel. A method for controlling a power semiconductor device includes: during a normal operation mode, controlling at least the wide bandgap material switch for switching a current through the power semiconductor device by applying corresponding gate signals to at least the wide bandgap material switch; sensing a failure in the power semiconductor device; and, in the case of a sensed failure, controlling the Si switch by applying a gate signal, such that a current is generated in the Si chip heating the Si chip to a temperature forming a permanent conducting path through the Si chip.

A power semiconductor device includes a Si chip providing a Si switch and a wide bandgap material chip providing a wide bandgap material switch, wherein the Si switch and the wide bandgap material switch are electrically connected in parallel. A method for controlling a power semiconductor device includes: during a normal operation mode, controlling at least the wide bandgap material switch for switching a current through the power semiconductor device by applying corresponding gate signals to at least the wide bandgap material switch; sensing a failure in the power semiconductor device; and, in the case of a sensed failure, controlling the Si switch by applying a gate signal, such that a current is generated in the Si chip heating the Si chip to a temperature forming a permanent conducting path through the Si chip.

A laser welding method using a laser welding jig having a plurality of pressing parts, includes a step of placing a second member on a first member; a step of pressing the second member with the plurality of pressing parts in a direction toward the first member to thereby form a gap between the first member and the second member at most 300 m; and a first welding step of laser-welding the first member and the second member by irradiating on a surface of the second member at a location between the pressing parts with laser light while conducting the step of pressing.

A laser welding method using a laser welding jig having a plurality of pressing parts, includes a step of placing a second member on a first member; a step of pressing the second member with the plurality of pressing parts in a direction toward the first member to thereby form a gap between the first member and the second member at most 300 m; and a first welding step of laser-welding the first member and the second member by irradiating on a surface of the second member at a location between the pressing parts with laser light while conducting the step of pressing.

Provided is copper paste for joining including metal particles, and a dispersion medium. The metal particles include sub-micro copper particles having a volume-average particle size of 0.12 m to 0.8 m, and micro copper particles having a volume-average particle size of 2 m to 50 m, a sum of the amount of the sub-micro copper particles contained and the amount of the micro copper particles contained is 80% by mass or greater on the basis of a total mass of the metal particles, and the amount of the sub-micro copper particles contained is 30% by mass to 90% by mass on the basis of a sum of a mass of the sub-micro copper particles and a mass of the micro copper particles.