Abstract:
Method and apparatus for controlling the deflection of an energy beam to impinge a workpiece with improved accuracy. A computer and interface unit direct the movement of the beam over a master target to learn and record addresses of impingement areas corresponding to those on a workpiece. Differential current flow in two conductive elements is used to determine accurate location of the address. Upon the substitution of a workpiece for the master target, impingement addresses can be selected without additional corrective deflection circuits.
Abstract:
The tracing of microcircuit wire patterns on photoresist overlaid substrates (circuit boards) by means of an electron beam. Pattern tracing is achieved by controlling the deflection of the beam in conjunction with the oscillatory motion of the substrate mounted on an oscillating stage. A feedback system from a grating on the stage provides synchronized pulses to a clock which in conjunction with the control data derived from a computer, provides control information for a desired circuit pattern.