Semikron has introduced a 100 per cent solder-free IGBT module for 22kW-150kW converters in electric and hybrid vehicles. SKiM has a five times higher temperature-cycling capability than modules that use a base plate and soldered terminals.
While some power semiconductor manufacturers are still working on soldered contacts to meet the high temperature requirements of the automotive industry, solder-free pressure contact technology and sintered chips offer the optimal solution to increase the temperature cycling capability to 10,000 cycles at ∆100K. The high temperature capabilities of Tjunction=175°C and Tambient=135°C allow one dedicated coolant loop to be omitted.
The solder-free pressure system and an internal laminated bus bar provide a homogeneous current distribution. Every IGBT and diode chip has its own connection to the main terminal. The result is a low module resistance of RCC'+EE' ≤ 0.3 mΩ compared to a value of approximately 1.1 mΩ from a soldered module. The connection to the driver board is also solder-free with springs for high temperature cycling and fast solder-free mounting.
The chips are not soldered but sintered to achieve the high power-cycling capability. The sinter joint is a thin silver layer that has a superior thermal resistance to a soldered joint and, due to the high melting point of silver, no joining fatigue, which leads to an increased service life.
Since there is no base plate, the connection of the direct-copper-bonded (DCB) substrate to the heat sink can ‘move’ without limiting the temperature-cycling reliability. SKiM withstands severe automotive environments, being highly resistant to shock and vibration stress.
The packaging and connection technology of the SKiM module fully exploits the capabilities of the silicon, resulting in a cost-efficient solution. .
Fast design-in is guaranteed by the standard terminal height of 17mm and a configuration similar to other six-pack modules. Two case sizes are available: SKiM 63 (120 x 160 mm) and SKiM 93 (150 x 160 mm).