New semicon adhesive propels autonomous driving forward

DELO has created a flexible electronics adhesive that permanently seals sensor housings airtight and reliably protects components such as image sensors. DELO DUALBOND BS3770 satisfies the stringent demands of the semiconductor and automotive industries and helps drive innovation in autonomous driving.

The autonomous driving trend comes with ever-stricter safety conditions. Therefore, reliable components such as image sensors are installed in LiDAR and RADAR systems. Sensor housings on PCBs must be hermetically sealed throughout their whole service life to maintain their function permanently with no interruption. However, previous solutions for hermetically sealing the housing and filter glass are reaching their limits due to these stricter conditions, failing to withstand the automotive industry tests, according to standard AEC-Q100.

DELO has developed this special electronics adhesive for semiconductor manufacturers to satisfy automotive suppliers' reliability and qualification test demands.

Unlike previously available adhesives, the newly developed adhesive is a flexible product with Young's modulus of less than 5MPa at room temperature. Due to its flexible properties starting from a temperature as low as approximately -50C, the adhesive can compensate for pressure changes that ensue, such as those caused by temperature changes, humidity differences, or heat input in the reflow process during production. Consequently, defects such as pop-ups or delamination do not occur, and the sensor is permanently protected.

The new adhesive can be precisely 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 using classic light fixation. Alternatively, it can be transferred to the B-stage, particularly relevant for bonding filter glasses with blackprint. At this stage, it performs an initial adhesion comparable to tape. Afterwards, the second component can be joined. Thanks to the adhesive's initial adhesion, the component is directly fixed to be entirely processed further. Final curing occurs in a convection oven at +150C within 40 minutes.

In addition to image sensors for LiDAR and RADAR applications, the adhesive is also employed in driver monitoring and 5G applications.

This new adhesive and other high-tech solutions for the semiconductor industry will be presented at SEMICON Europe, Booth B2467, Munich, 14-17 November 2023.