DELO MONOPOX EG2596 is a die-attach adhesive characterized by high strength even after aging and high humidity. The modelling is controlled, thanks to the high thixotropy index of the order of about 9; the delivered drops can be only 250 µm in diameter.

DELO has presented MONOPOX EG2596, a die-attach adhesive developed for semiconductor and SMT applications. It is a heat-curing one-component epoxy resin. After tests with machine integrator ASM Assembly Systems, this adhesive has been proven to possess after seven days of storage at 85 % relative air humidity and a temperature of +85 °C. It maintains its strong adhesion even after typical aging tests, like the MSL1 test, in accordance with JEDEC standard. When using 1×1 mm² silicon dies, the test revealed adhesion values of 47 N on FR4 substrate and 62 N on gold.

Controlled manner

Another advantage of DELO MONOPOX EG2596 is its high thixotropy index of about 9. The higher the index value, the more flow-resistant the dispensing pattern after the dispensing process. The thixotropic properties of DELO MONOPOX EG2596 ensure that the adhesive can be applied very finely in a low-viscous state due to the shear in the dispensing valve. After dispensing, viscosity increases again in fractions of a second, preventing the adhesive from flowing. This allows the die attach to be built up in individual droplets and then shaped in a controlled manner, without the adhesive spreading into areas that should remain adhesive-free. Even during heat curing, the adhesive drop remains dimensionally stable.

Drop sizes down to below 250 µm

The flow properties of DELO MONOPOX EG2596 are designed to allow dispensing by means of jet valves and needles. Thanks to this flexibility, the adhesive provides versatile application options. Tests conducted jointly by DELO and its technology partner ASM Assembly Systems show the excellent dispensing properties of the die attach adhesive. The jet valve allows the adhesive to be dispensed contactless and upside down. The adhesive is applied directly to the specific component and not to the printed circuit board, a solution that ensures fast and highly precise processes. Depending on the dispensing equipment, drop sizes down to below 250 µm can be achieved. Even after several shots, the dispensing patterns remain uniform and do not show typical unwanted effects such as satellite droplets.

Curing takes place at +130 °C in 10 minutes. The fluorescent adhesive is available in 10 cc cartridges and can be ordered in quantities of just one. Once opened, the product can be processed in a user-friendly manner for up to seven days in a standard climate of +23 °C.