This discloses a probe structure which does not rely on cantilevered wire and which has improved and controlled contact pressure between the probe contacts and the I/O pads on a semi-conductor chip and which comprises a plurality of conductive contact electrodes, electrically coupled to respective leads,...http://www.google.co.uk/patents/US5625298?utm_source=gb-gplus-sharePatent US5625298 - Semi-conductor chip test probe
