Patent ID: 7667475

Claim:
A portable pack, comprising: a portable supporting structure including first and second components for holding the substrate therebetween, a substrate carrying a microelectronic circuit and having a plurality of terminals connected to the microelectronic circuit, wherein the second component includes a signal distribution board and a contactor, wherein a coefficient of thermal expansion (CTE) ratio of a CTE of the signal distribution board to a CTE of the contactor is not equal to 1; a plurality of contacts on the second component, the contacts matching the terminals for making contact to the terminals, and the components are movable relative to one another to ensure proper contact between the contacts and the terminal; and a first interface, on the portable supporting structure and connected to the contacts, for connection to a second interface, on a stationary structure when the portable supporting structure is removable and held by the stationary structure, wherein the contactor heats from first contactor temperature to a second contactor temperature during testing of the microelectronic circuit, and the signal distribution board heats from a first signal distribution board temperature to a second signal distribution board temperature, and a temperature change ratio, being a difference between the second signal distribution board temperature and the first signal distribution board temperature to a difference between the second contactor temperature and the first contactor temperature, multiplied by the CTE ratio, is closer to 1 than the CTE ratio.