Abstract: A tertiary positioner system (80) of this invention employs X- and Y-axis translation stages (86, 88), galvanometer-driven mirrors (64, 66), and a fast steering mirror (“FSM”) (120) to direct a laser beam (90) to target locations (121) on a workpiece (92). A positioning signal is received by a low-pass filter (103) that produces filtered position data for driving the X- and Y-axis translation stages. The actual positions of the X- and Y-axis translation stages are subtracted from the unfiltered positioning data to produce an X-Y position error signal for driving the galvanometer-driven X- and Y-axis mirrors. The actual mirror positions are subtracted from the actual positions of the X- and Y-axis translation stages to generate a positional error signal representing the difference between the commanded and actual positions of the laser beam. The positional error signal drives the FSM to rapidly correct any positional errors.

Abstract: Laser beam positioners (300, 340) employ a steering mirror (236, 306) that performs small-angle deflection of a laser beam (270) to compensate for cross-axis (110) settling errors of a positioner stage (302). A two-axis mirror is preferred because either axis of the positioner stages may be used for performing work. In one embodiment, the steering mirror is used for error correction only without necessarily requiring coordination with the positioner stage position commands. A fast steering mirror employing a flexure mechanism and piezoelectric actuators to tip and tilt the mirror is preferred in semiconductor link processing (“SLP”) applications. This invention compensates for cross-axis settling time, resulting in increased SLP system throughput and accuracy while simplifying complexity of the positioner stages because the steering mirror corrections relax the positioner stage servo driving requirements.

Abstract: A multi-rate, multi-head positioner (150) receives and processes unpanelized positioning commands to actuate slow stages (56, 58) and multiple fast stages (154) that are mounted on one of the slow stages to simultaneously position multiple tools (156) relative to target locations (162) on multiple associated workpieces (152). Each of the fast stages is coupled to a fast stage signal processor (172) that provides corrected position data to each fast stage positioner to compensate for fast stage nonlinearities and workpiece placement, offset, rotation, and dimensional variations among the multiple workpieces. When cutting blind via holes in etched circuit boards (ECBs), improved throughput and process yield are achieved by making half of the tools ultraviolet ("UV") lasers, which readily cut conductor and dielectric layers, and making the other half of the tools are infrared ("IR") lasers, which readily cut only dielectric layers.

Abstract: A multi-rate positioner system (50) receives unpanelized positioning commands from a database storage subsystem (64), profiles the commands (72) into a half-sine positioning signal, and further processes the signal into a low-frequency positioning signal (LFP) and a high-frequency positioning signal (HFP) for actuating respective slow (56, 58) and fast (54) positioners to target locations on a workpiece (62). The slow and fast positioners move without necessarily stopping in response to a stream of positioning command data while coordinating their individually moving positions to produce temporarily stationary tool positions (140) over target locations defined by the database. The multi-rate positioning system reduces the fast positioner movement range requirement while providing significantly increased tool processing throughput.