Ixys Corporation

Littelfuse, Inc.

Ixys Semiconductor Gmbh

Thomas Spann

Kang Rim Choi

Holger Ostmann

Ira Balaj-Loos

Elmar Wisotzki

Frank Ettingshausen

Heiko Knoll

Werner Weidenauer

Yong Ai-Ong

Provided herein are semiconductor packages with improved electrical contacts (e.g. pins). In some embodiments, an assembly may include a substrate and an electrical contact coupled to the substrate, the electrical contact consisting of a first component defined by a complex 3D designed receiving pin. The electrical contact may further include a second component defined by another complex 3D designed penetrating pin, wherein the first component engages the second component to deform mechanically and to weld when the first component and the second component are coupled together.

Electrical contact for semiconductor package

A semiconductor die having a metal tab connected thereto. The metal tab includes at least one slot on at least one side of the metal tab, wherein the at least one slot i) creates an opening between at least two portions of the metal tab and ii) exposes the semiconductor die in relation to the metal tab. The semiconductor die can be a silicon (Si) die and the metal tab can be a copper (Cu) tab, where the at least one slot includes at least four slots corresponding to each of at least four sides of the metal, and wherein with respect to each of the at least four sides, each corresponding slot i) creates an opening between at least two portions of the Cu metal tab and ii) exposes the Si semiconductor die in relation to the Cu metal tab.

Metal tab for chip assembly

A power semiconductor device module includes, among other parts, a DMB structure. The DMB structure includes a ceramic sheet, a top metal plate that is directly bonded to the top of the ceramic, and a bottom metal plate that is directly bonded to the bottom of the ceramic. A power semiconductor device die is attached to the top metal plate. The bottom surface of the bottom metal plate has a plurality small cavities. When the bottom metal plate is attached to another metal member, a material between the plate and the member (for example, thermal grease or a PCM or solder) is forced into the cavities. This results in an improvement in thermal transfer between the plate and the member. Such cavities can alternatively, or in addition, be included on a metal surface other than a DMB, such as the bottom surface of a baseplate of the module.

Heat transfer plate having small cavities for taking up a thermal transfer material

A power semiconductor device module includes a metal baseplate and a plastic housing that together form a tray. Power electronics are disposed in the tray. A plastic cap covers the tray. Electrical press-fit terminals are disposed along the periphery of the tray. Each electrical terminal has a press-fit pin portion that sticks up through a hole in the cap. In addition, the module includes four mechanical corner press-fit anchors disposed outside the tray. One end of each anchor is embedded into the housing. The other end is an upwardly extending press-fit pin portion. The module is manufactured and sold with the press-fit pin portions of the electrical terminals and the mechanical corner anchors unattached to any printed circuit board (PCB). The mechanical anchors help to secure the module to a printed circuit board. Due to the anchors, screws or bolts are not needed to hold the module to the PCB.

Power semiconductor device module having mechanical corner press-fit anchors

Top and bottom metal plates of a DMB panel stack are simultaneously direct-bonded to the central ceramic sheet in a single high-temperature step. During this step, the DMB panel rests on an array of very small upwardly projecting ceramic contacts of a ceramic carrier. An amount of unoxidized carbon (e.g., a layer of graphite) is disposed on each contact projection such that an amount of carbon is disposed between the top of the contact projection and the metal oxide skin of the bottom metal plate. The carbon bonds with oxygen from the metal oxide skin, thereby preventing connection or direct-bonding of the ceramic contact projection to the second metal plate. This reduces imperfections in the metal of the bottom plate and reduces the amount of ceramic particles bonded to metal at contact sites. As a result, less post-bonding processing is required to make a high quality DMB substrate.

Direct metal bonding on carbon-covered ceramic contact projections of a ceramic carrier

A packaged inverse diode device exhibits superior commutation robustness. The device includes a stack of inverse diodes disposed within a housing. Each adjacent pair of inverse diodes is bonded together by an intervening DMB (Direct Metal Bonded) substrate structure. At one end of the stack of diode dice and DMB substrate structures is attached a first metal terminal. A second metal terminal is attached to the other end of the stack. The two terminals serve as package terminals of the overall device. In a novel method, the device undergoes severe commutation. A large forward current is made to flow through the diode stack, followed by a rapid reversal of the voltage across the stack to a large reverse polarity voltage. Despite a substantial rate of change of the commutation current at the onset of the reverse voltage condition, the inverse diode device is not damaged.

Inverse diode stack

The baseplate of a power semiconductor device module makes reliable and superior thermal contact with a heatsink when fixed to the heatsink. The baseplate includes a rectangular plate portion, a first downward-extending peripheral heel extension portion, and a second downward-extending peripheral heel extension portion. In one example, the plate portion has four mounting holes for receiving mounting bolts. There is one mounting hole located adjacent each of four corners of the rectangular plate portion. The central portion of the bottom surface of the plate portion has a slightly convex downward shape. The strip-shaped first heel extension portion extends along a first edge of the bottom surface. The strip-shaped second heel extension portion extends along a second edge of the bottom surface opposite the first edge. Each of the first and second heel extension portions extends downward from the bottom surface for a distance of between thirty and five hundred microns.

Power semiconductor device module baseplate having peripheral heels

A power module includes a substrate DMB (Direct Metal Bonded). A novel bridging DMB is surface mounted to the substrate DMB along with power semiconductor device dice. The top metal layer of the bridging DMB has one or more islands to which bonding wires can connect. In one example, an electrical path extends from a module terminal, through a first bonding wire and to a first location on a strip-shaped island, through the island to a second location, and from the second location and through a second bonding wire. The strip-shaped island of the bridging DMB serves as a section of the overall electrical path. Another bonding wire of a separate electrical path passes transversely over the strip-shaped island without any wire crossing any other wire. Use of the bridging DMB promotes bonding wire mechanical strength as well as heat sinking from bonding wires down to the substrate DMB.

Bridging DMB structure for wire bonding in a power semiconductor module

Bridging DMB structure for wire bonding in a power semiconductor device module

A packaged power semiconductor device is provided with voltage isolation between a metal backside and terminals of the device. The packaged power semiconductor device is arranged in an encapsulant defining a hole for receiving a structure for physically coupling the device to an object. A direct-bonded copper ('DBC') substrate is used to provide electrical isolation and improved thermal transfer from the device to a heatsink. At least one power semiconductor die is mounted to a first metal layer of the DBC substrate. The first metal layer spreads heat generated by the semiconductor die. In one embodiment, the packaged power semiconductor device conforms to a TO-247 outline and is capable of receiving a screw for physically coupling the device to a heatsink.

Electrically isolated power semiconductor package with optimized layout

The invention relates to a method for the manufacture of double-sided metallized ceramic substrates according to the direct-bonding process. The method enables a ceramic substrate to be bonded to a metal plate or foil on the upper side and the underside in only one process sequence. The composite to be bonded is located on a specially designed carrier structured on the upper side with a plurality of contact points. After the bonding process the composite of metal plates and ceramic substrate can be detached from the carrier free of any residue.

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Furth, Germany

Thomas Spann