Cast Silicone Flex Circuit Vacuum Tool

Vacuum Pickup Tool For Flexible Kapton Circuit
Silicone Casting Mold

This is a vacuum pickup tool used to transfer the position of two linked Kapton flexible circuit boards. The physical irregularity of the circuit board surfaces due to internally laminated electrical traces made sealing a vacuum difficult so a mold was designed to cast a more compliant interface that would conform to the board.

The material had to be non-volatile, electro-statically dissapative, must be compatible with some adhesion promoter to encourage bonding to an aluminum substrate along with mechanical locking features. It of course also had to be complaint and have a large elongation percentage. We have yet to narrow the final result but are in the realm of 30A Shore Silicone.

The aluminum substrate acts to stiffen the gasket as a whole, and also functions as the vacuum chamber.

Because the locations of the surface mount components and ASIC’s has yet to be finalized, this is just an early prototype. There will be additional features added to the mold in order to avoid said SMD, and a significant number of extremely fragile ultrasonic wire-bonds from the ASIC’s to the flex-circuit.