A 70 GHz chip to printed circuit board interconnect using Kapton flexible substrate

A method of connecting integrated circuits to Printed Circuit Board (PCB) carriers with broadband frequency response is presented using Kapton film as a flexible, interconnecting substrate. Flip chip processing is applied using a simple and effective technique to curve the flexible substrate, accommodating different heights between the chip and PCB. Measurements of a test assembly show a return loss more than 15 dB and insertion loss less than 1.0 dB from DC to 70 GHz.