Resilient contact structures are mounted directly to bond pads on semiconductor dies, prior to the dies being singulated (separated) from a semiconductor wafer. This enables the semiconductor dies to be exercised (e.g., tested and/or burned-in) by connecting to the semiconductor dies with a circuit board...http://www.google.de/patents/US5864946?utm_source=gb-gplus-sharePatent US5864946 - Method of making contact tip structures
