Optical signal injection for high-speed wafer level function test of integrated circuits

Conventional needle probe techniques do not permit wafer level tests at frequencies above about 100 MHz. As an alternative to special probes like microwave strip lines optical inputs have been designed which have been shown to operate up to 800 MHz in 1.2 /spl mu/m BiCMOS technology. They are process compatible and require an area less than that of a standard aluminum pad.