Delo Dualbond BS3770 is said to permanently seal sensor housings airtight and thus protect components such as image sensors.
According to Delo, the autonomous driving trend comes with ever-stricter safety requirements. Therefore, reliable components such as image sensors are installed in Lidar and Radar systems. Sensor housings on PCBs must be hermetically sealed throughout their entire service life in order to maintain their function permanently without interruption. However, previous solutions for hermetically sealing the housing and filter glass are reaching their limits due to these stricter requirements, failing to withstand the tests of the automotive industry, according to standard AEC-Q100.
The newly developed adhesive comes with a Young's modulus of less than 5 MPa at room temperature. Due to its flexible properties starting from a temperature as low as approximately -50 °C, the adhesive can compensate for pressure changes that occur, such as those caused by temperature changes, humidity differences, or heat input in the reflow process during production. As a result, defects such as pop-ups or delamination do not occur, and the sensor is permanently protected.
Delo Dualbond BS3770 can be applied by needle dispensing while maintaining narrow and high bondlines. Curing takes place in two consecutive steps using UV light and heat. After dispensing, the adhesive is fixed in a few seconds by means of classic light fixation. Alternatively, it can be transferred to the B-stage, which is particularly relevant for bonding filter glasses with blackprint. At this stage, it achieves an initial adhesion comparable to tape. Afterwards, the second component can be joined. Thanks to the adhesive’s initial adhesion, the component is fixed so that it can be entirely processed further. Final curing takes place in a convection oven at +150 °C within 40 minutes.
In addition, Delo Dualbond BS3770 is used in driver monitoring and for 5G applications.