A semiconductor device includes an insulating substrate formed by integrating a ceramic base plate and a cooling fin; a multiple of plate interconnection members; and a plurality of semiconductor elements. The one faces of the semiconductor elements are bonded to the ceramic base plate of the insulating substrate with a chip-bottom solder, and the other faces thereof are bonded to the plate-interconnection members with a chip-top solder so that plate interconnection members correspond respectively to the semiconductor elements. The chip-bottom solder and the chip-top solder both contain mainly Sn and 0.3-3 wt. % Ag and 0.5-1 wt. % Cu. This allows the semiconductor device to be reduced in size without impairing heat dissipation.

A semiconductor device includes an insulating substrate formed by integrating a ceramic base plate and a cooling fin; a multiple of plate interconnection members; and a plurality of semiconductor elements. The one faces of the semiconductor elements are bonded to the ceramic base plate of the insulating substrate with a chip-bottom solder, and the other faces thereof are bonded to the plate-interconnection members with a chip-top solder so that plate interconnection members correspond respectively to the semiconductor elements. The chip-bottom solder and the chip-top solder both contain mainly Sn and 0.3-3 wt. % Ag and 0.5-1 wt. % Cu. This allows the semiconductor device to be reduced in size without impairing heat dissipation.

A coaxial laser metal deposition head includes a wire guide and a plurality of laser optical units. The wire guide defines a wire guide axis. The laser optical units are distributed around the wire guide axis. Each of the laser optical units is connected to a separate laser and each defines a beam axis. The optical units are fixed relative to the wire guide and in a first condition are positioned to allow each of the beam axes to intersect the wire guide axis at a common point.

A laser reflow apparatus reflows solder bumps disposed on a side of a semiconductor chip in a workpiece and included in an irradiation range on the workpiece by applying a laser beam to an opposite side of the semiconductor chip. The laser reflow apparatus includes a spatial beam modulation unit including a laser power density setting function to locally set the laser power density in the irradiation range of a laser beam emitted from a laser beam source, and an image focusing unit including an image focusing function to focus the laser beam emitted from the laser beam source and apply the focused laser beam to the irradiation range on the workpiece.

A component includes a first part in which a first junction part is configured, a second part in which a second junction part and a cross junction part intersecting the second junction part are configured. The second junction part and the first junction part are welded at a preceding weld. The component also includes a third part in which a third junction part is configured. A part of the third junction part is overlapped with an opposite part of the first junction part, a remaining part of the third junction part is overlapped with the cross junction part, and the first part and the second part are welded to the third part at a following weld at each of the overlapped parts.

The present disclosure is directed to a compact vertical oven for reflow of solder bumps for backend processes in semiconductor wafer assembly and packaging. This disclosure describes a vertical oven which uses a plurality of wafers (e.g., an example value is 50-100 wafers) in a batch with controlled injection of the reducing agent (e.g. formic acid), resulting in a process largely free of contamination. This disclosure describes controlled formic acid flow through a vertical system using laminar flow technology in a sub-atmospheric pressure environment, which is not currently available in the industry. The efficacy of the process depends on effective formic acid vapor delivery, integrated temperature control during heating and cooling, and careful design of the vapor flow path with exhaust. Zone-dependent reaction dynamics managed by vapor delivery process, two-steps temperature ramp control, and controlled cooling process and formic acid content ensures the effective reaction without any flux.

The disclosure describes techniques for joining a first part including a ceramic or a CMC and a second part including a ceramic or a CMC using brazing. A technique may include positioning a filler material in a joint region between the first and second parts and a metal or alloy on a bulk surface of the filler material. The metal or alloy may be locally heated to melt the metal or alloy, which may infiltrate the filler material. A constituent of the molten metal or alloy may react with a constituent of the filler material to join the first and second parts. Another technique may include depositing a powder that includes the filler material and the metal or alloy in the joint region. Substantially simultaneously with depositing the powder, the powder may be locally heated. A constituent of the molten metal or alloy may react with a constituent of the filler material to join the first and second parts.

A method for selectively adhering braze powders to a surface comprises applying a binder material to a surface, depositing a braze powder on the binder material, and then directing a laser beam onto the braze powder while the laser beam moves along a predetermined path relative to the surface. The laser beam selectively heats the braze powder and the binder material along the predetermined path such that the binder material is removed and the braze powder is sintered and bonded to the surface. Thus, a braze deposit is formed at one or more predetermined locations on the surface. After forming the braze deposit, excess braze powder and binder material, that is, the braze powder and binder material not selectively heated by the laser, are removed from the surface.

A method for selectively adhering braze powders to a surface comprises applying a braze powder to a surface, and then directing a laser beam onto the braze powder while the laser beam moves along a predetermined path relative to the surface. The laser beam selectively heats the braze powder along the predetermined path such that the braze powder is sintered and bonded to the surface. Thus, a braze deposit is formed at one or more predetermined locations on the surface. After forming the braze deposit, excess braze powder, that is, the braze powder not selectively heated by the laser, is removed from the surface.

A joining device and method for laser-based joining of two components includes a first laser radiation source, a first radiation guide connected to the first radiation source to couple first laser radiation into the first radiation guide, a second laser radiation source, at least one second radiation guide connected to the second radiation source to couple second laser radiation into the second radiation guide, and a focusing device coupled to the laser radiations and focusing them at a distance from each other into a joining zone of the components. To reduce installation effort, the focusing device focuses the first and second laser radiations through a common beam path and a coupling device is connected on its input side to the first and second radiation guides and on its output side to the focusing device. The coupling device couples the first and second laser radiations into the common beam path.