In current technology, the edge definition that can be achieved by the photoresist process is approximately ten times sharper than the registration accuracy that can be maintained over a workpiece of any reasonable size. A description is presented of an attempt to improve registration through feedback from the workpiece itself; the servo signal is generated by the photoresist-exposing radiation, a submicron-diameter electron beam. Using this technique, the gate electrode of a field-effect transistor (FET) has been automatically positioned relative to the channel.