TAGS: Epoxy Adhesives Sealants
Master Bond launches Master Bond Supreme 3HTND-2DM, a rapid curing, toughened, one part epoxy system used for the dam-and-fill method for chip-on-board encapsulation.
Essentially, there are two methods to protect chips and their wire bonds. One method is referred to as glob top, where the encapsulating system is dispensed and applied directly to the area to be protected. This kind of system is dispensed with precise and very controlled flow. A glob top should leave no area uncovered, nor should it have excess flow.
The alternative approach is referred to as dam-and-fill. This approach entails dispensing the damming material around the area to be encapsulated. This material will cure in place and will not run, in essence forming a dam. Then an encapsulating material is applied to cover the remaining area to be protected.
Cures Readily at Elevated Temperatures
Master Bond Supreme 3HTND-2DM requires no mixing and cures readily at elevated temperatures, with the minimum curing schedule being 20-30 minutes at 250°F or 5-10 minutes at 300°F. As mentioned above, it is not premixed and frozen and its working life at room temperature is unlimited. It has a paste consistency with no flow while curing and is ideal for forming a barrier. The barrier itself is structurally sound with good thermal conductivity.
This epoxy bonds well to a wide variety of substrates used in electronics including silicon and other semiconductors, metals, ceramics and many plastics. Its is from -100°F to +400°F. It has very good epoxy type chemical resistance It is inherently tough and withstands thermal cycling well. Its color is black.
This epoxy has passed the NASA low outgassing test which allows it to be used in vacuum, aerospace, electro-optic and other related applications. This epoxy is also considered to have low ionic levels of chlorine, sodium and potassium(<10 ppm). These special product attributes allow this epoxy to fit nicely as a barrier material in electronic and semiconductor applications. In fact, it product property profile enables it to be used in other types of bonding and sealing applications.
Source: Master Bond