Laser technology solution specialist Altechna Co is basing its Alt-SCA femtosecond laser micromachining system around Aerotech’s ANT130 series linear motor driven nano positioning stages in a customised 3-axis XYZ configuration that includes a granite bridge support structure and a pneumatically counterbalanced vertical axis
The synchronisation between the one nanometre resolution positioning system and the laser’s firing pattern is precisely and crucially controlled with the advanced PSO (Position Synchronised Output) command from Aerotech’s software based A3200 motion controller which is built into Altechna’s SCA (System Control Application) front end software using .NET class libraries.
Altechna has developed its SCA software with C++ and C# to provide a flexible yet powerful control platform for laser micromachining that is capable of three levels of simple-to-complex micro-fabrication where, at the basic level, a WYSIWYG equipped GUI is able to convert complex positioning information from BMP or PLT files without G-code programming.
Moreover, SCA can be used to program multiplex trajectories using mathematical functions. At the highest level, programmers may write micro-fabrication code in C++ and C#.
The femtosecond laser machining system integrates the complete Aerotech motion sub-system including rack mounted linear servo-amplifiers with a 10W Yb:KGW (1030nm) femtosecond laser source, machine vision, beam shaping optics and a galvo scanning head with fabrication speeds up to 35,0000 pixels per second with 25,400dpi resolution. Combining high processing speed and large area positioning capability with nanoscale resolution and sub-micron accuracy, the AltSCA suits research and industrial users for development and/or high throughput manufacture of surface or 3D micro-nano structures from MEMS sensors and optical micro-elements fabrication to microchip repairs and waveguide production.
Altechna, based in Vilnius, Lithuania works closely with the Laser Nanophotonics Group at Vilnius University where Aerotech equipment is being used for research involving the fabrication of fully functioning 100m microlenses.
Altechna is also working on fully integrating Galvo-scanners with the ANT130 positioning system by using Aerotech’s Nmark SSaM (Synchronized Scanner and Motion module). This will allow wide-format bitmaps to be processed continuously by enabling laser micromachining of structures and patterns that exceed he Galvo scanner’s normal field of view.
The AltSCA femtosecond laser machining system uses an integrated ANT130 XY series low profile X-Y stage that supports the object workpiece and a separate vertically mounted Z-axis stage for laser head manipulation. The Z-axis is fixed to the granite bridge structure and its pneumatic counterbalance is based on a tried-and-tested Aerotech design. The large granite base provides stability for the positioning system and the complete assembly includes all cabling and provision for air supply.
The ANT130 series has a nominal width of 130mm and is available in travel ranges from 35mm to 160mm, in a choice of two accuracy grades up to +/-250 nanometres to suit high or ultra-high precision requirements. The performance characteristics (pitch, yaw and roll etc) ensure the combined flatness, straightness, perpenicularity, abbe error, and all other critical geometric specifications do not compromise the nanometre level machining requirements for this application. The compact design includes anti-creep cross roller bearings and a centre driven brushless /non-cogging linear servomotor with one nanometre resolution encoders.
The three-axis ANT130 is a part of Aerotech’s nano Motion Technology (nMT) positioning range that brings together linear, rotary and goniometric stages to provide precision, rapid acceleration, high speed and ultra-fine resolution for nanometre resolution positioning. With zero-backlash and hysteresis in combination with high speed encoder feedback processing and real-time axis calibration, the nMT range is providing the enabling technology for many demanding applications where large area/high throughput positioning involves nanometre level structuring – suitable for ultra fast laser micromachining.
