“High voltage applications like those found in automotive ADAS systems, EVs, industrial motor controls, and high-efficiency power supplies require superior electrical and thermal performance,” says Henkel’s Global Market Segment Head for Semiconductor Packaging Materials, Ramachandran Trichur. “Currently, the only viable die attach alternative to Pb solder – which will soon be phased out and cannot meet certain thermal demands – is sintered silver (Ag). Henkel pioneered pressure-less sintering die attach, allowing the use of standard, low-stress processing, and we have now formulated our fourth and highest thermal conductivity material to date, which tackles the stringent thermal and electrical requirements of next-generation power packages.”
Henkel’s newest pressure-less sintering die attach formulation meets multiple metrics for power semiconductors like MOSFETs, which are increasingly incorporating silicon carbide (SiC) and gallium nitride (GaN) materials as alternatives to silicon (Si) for improved efficiency. Loctite Ablestik ABP 8068TI is compatible with traditional Si and newer wide-bandgap semiconductors, among other power discrete devices. The 165 W/m-K ultra-high thermal conductivity die attach adhesive has demonstrated excellent sintering properties with good adhesion on copper (Cu), pre-plated frames (PPF), silver (Ag), and gold (Au) lead frames, robust electrical conductivity and stable RDS(on) after 1,000 hours of thermal cycling, and MSL 3 reliability. Recommended for dies measuring 3.0 mm x 3.0 mm or smaller, Loctite Ablestik ABP 8068TI fully cures at 175° C or above to form a rigid sintered Ag network in the bulk epoxy and at the interface. Because pressure-less sintering is a drop-in replacement for standard die attach, high pressure is not required to achieve this robust structure, eliminating stress on thin die. Workability of the material is also notable at three hours of void-free open time and 24 hours of stage time with no degradation in shear strength.
As Trichur concludes, the power device market will only accelerate in application uses and performance requirements, making high-capability, high thermal die attach solutions an operational necessity: “There is an increased demand for power devices across market sectors, including automotive, industrial power storage and conversion, and aerospace, to name a few. For power semiconductors, sintered die attach is the prevailing and most reliable solution to deliver the die attach strength, integrity, and thermal and electrical conductivity required. Loctite Ablestik ABP 8068TI provides all this in a formula that enables simple processing to protect thinner, more complex dies.”
To discover more about Henkel’s pressure-less sintering portfolio, visit this resource.