Custom Interconnect Ltd installs Boschman Sinterstar Innovate F-XL and Pre-heat/Cooling Tower system for SiC Power module manufacture
As part of its continued investment in SiC power module development and production enabled by APC15 @ FutureBEV and InnovateUK GaNSiC funding, CIL will soon have production capability for high pressure Silver Sintering of WBG / SiC die processing.
CIL believes this capability is unique in the UK and one of only 3 production capable systems in Europe.
As the Automotive market transitions from predominantly internal combustion engines (ICE) to plug in hybrid electric vehicles (PHEV) and full battery electric vehicles (BEV) the use of SiC power switching will become the dominant technology throughout the entire automotive industry. With battery voltages of 800V fast becoming the norm and switching currents of 500 – 700A, the power densities that the power modules have to switch are enormous. Therefore, the thermal management of the SiC based power module is one of the most critical focus points in BEV development. Traditional Silicon (Si) die attach methods such as conductive epoxies and eutectic solders simple cannot thermally perform at these power densities, so have been replaced by Silver Sinter die attach techniques. This started with low pressure / pressureless Silver Sinter, but for optimum thermal transfer High pressure Silver Sintering is the only solution. There are a very small number of home-built High pressure Silver sinter systems at facilities in the UK, but the investment by CIL of the Boschman Sinterstar Innovate F-XL is the only production installation in the UK and one of only three in UK/EU. Customers such as BMW on APC15@FutureBEV and other Tier 1 automotive customers insist on nothing less and APC15@FutureBEV and Innovate UK project GaNSiC has enabled CIL to make this significant investment for the future of Automotive manufacture in the UK.
As well as the base Sinter system shown in the picture above CIL also purchased the Boschman Pre-heat and Cooling Tower system to enable faster process times.
What this system provides that is unique to high pressure Silver Sintering is the application of extremely high pressure during the sintering operation which results in thermal conductivities of > 150W m/K and operating temperatures near 1000 degC. Most epoxies / eutectic solders / pressureless Silver Sintering never exceed 100W m/K and therefore this technology gives >50% thermal improvement. But the pressures involved are significant as can be seen by a close up of the press mechanism picture below.
Once commissioned, the two tower systems of Pre-heat and Cooling Tower and Sinter press will work in combination to provide a prototype / pre-production / production capability at CIL. This will enable to CIL to provide the only production capability for the high-pressure Silver Sintering of SiC in the UK. Once full production commences, CIL will make further investments on all necessary production equipment.
This Boschman Sinterstar Innovate F-XL is part of an overall series of investments that are necessary for production capability in the UK for future Automotive / Aerospace / Power generation power modules. To date the other investments made include K&S Asterion Heavy Gauge wire/ribbon bonder, Nordson SONOSCAN Gen7 Scanning Acoustic Microscope (CSAM) and soon to be added DATACON 2200EVO Automatic die bonder. These essential pieces of capital equipment when coupled with CIL’s extensive existing production equipment/capability will ensure CIL is ready for our low carbon transportation future and ensures that UK manufacturing stays are the forefront of this technology.