Multi-GHz elastomeric connectors for complex hybrids and chip carriers

In attempting to achieve optimum or almost reflectionless signal transmission in gigahertz-frequency circuitry on a printed-circuit board (PCB), signal routing via microstrip transmission lines is used. However, when the conventional practice of interconnecting hybrids or chip carriers to only one plane on the PCB is followed, unwanted reflections result because the transmission line grounds are not directly connected. Elastomeric connector systems make it possible to connect signals (and grounds) of the microstrip transmission lines of a PCB directly to the microstrip transmission lines of a hybrid or VLSI chip carrier by aligning the transmission lines of the PCB and hybrid in a coplanar fashion and then accurately positioning small contacts bonded to elastomer over the aligned transmission lines. The PCB and hybrid are of the same thickness and are sandwiched between a metal head sink and the elastomeric contacts nested into the plastic frame. Contact force is applied by tightening the plastic frame into which the elastomer and its attached contacts are nested. The related microstrip transmission line ground planes are thus directly connected by the metal heat sink