SKiiP® Technology
Longevity and High Power Cycling Capability
The SKiiP Technology introduced by Semikron Danfoss in 1992 is a special pressure contact technology with advantages in power density, longevity, reliability, and cost. The most important feature the lack of baseplate. The DBC substrate on which the chips are mounted is pressed onto the heatsink by either pressure moulds in the housing or with structured pressure elements between the chips.
The main advantage of this construction technology is that no adhesive bond connection such as a large soldered area exists between the DBC substrate (thermal expansion coefficient of 4...7·10-6/K), and the Cu baseplate (thermal expansion coefficient of approximately 17.5·10-6/K). This avoids lifetime-related mechanical stresses between baseplate and DBC substrate that occur in conventional modules due to temperature changes. Due to the absence of the baseplate and the lower solder layer, the thermal resistance between the chips and the heatsink decreases. Thus, a higher power density can be achieved in the steady state operation compared to baseplate modules. The elimination of the thermo-mechanical stress between the baseplate and DBC substrates also allows the use of very large substrates instead of several small substrates soldered to a common base and connected by additional elements.
The SKiiP Technology is used by Semikron Danfoss in various product groups and combined with different power and control terminal connections.
Contact Technology of Power and Control Terminals
Product group
- SKiiP
- SKiM 4
- SKiM 93
- MiniSKiiP
- SEMITOP, some SEMIPONT
Power terminals
- Pressure contact
- Solder contact
- Pressure contact
- “SPRiNG” contact
- Solder contact
Control terminals
- “SPRiNG” contact
- “SPRiNG” contact
- “SPRiNG” contact
- “SPRiNG” contact
- Solder contact
Within the modules (e.g. SKiiP 4, SKiM 93), the load terminals are designed with sandwiched, low inductance busbars. A finger structure on the busbars acts both as a symmetrical electrical contact to the individual IGBT and diode chips as well as a uniform pressure element between the DBC substrates and heatsink.
In contrast, the SPRiNG system of the MiniSKiiP products is adapted to the use of printed circuit boards. The pressure of the DBC substrate to the heatsink is largely provided by springs which, at the same time, provide the electrical contacts to the PCB. The planar level of the PCB above the contacts is ensured by a rigid lid. The necessary contact pressure between the lid, PCB, module, and heatsink is achieved by tightening the mounting screw(s).
