Very high density probing

A discussion is presented on some of the problems encountered with probing at the wafer level and how this probe card technology helps to overcome those problems. Advancements needed in probe card technology include smaller pitches, faster speeds, bumped pads, internal and multidie probing. With the density of the die increasing, the pitch between pads on the die is being reduced. A pitch of 4 mils or less is common for faster, more complex devices, resulting in an almost unlimited growth of signal pins. Tape automated bonding (TAB) necessitates that bumps be placed on the pads of the die. Bumped pads must then be probed. Internal and multidie probing, although not a recent development, is being requested more often to help improve throughput