Critical-dimension system inspects MEMs
DECEMBER 12--NanoVia (Londonderry, NH) has delivered its first high-speed critical-dimension inspection and alignment system for applications in MEMs and MEOMs volume-manufacturing applications. The system incorporates a patent-pending illumination method that uses a hybrid Nomarski incident-light differential interference contrast prism technology integrated into a coaxial illuminated scope with variable attenuator and analyzer/polarizing elements. There is a 0.35-NA objective and a dual fixed-magnification camera setup, offering two separate magnifications within the same scope.
The system can be configured with standard Pulnix RS-170 NTSC cameras or Pulnix Camera Link digital megapixel cameras for applications requiring high resolution to maximize GR&R. The software is based on a seamless vision-to-motion package developed by NanoVia, which integrates a Matrox Meteor-II / Camera Link frame grabber to a Delta Tau Multiaxis PMAC motion-control platform. The system can align and measure to within +/-0.5 μm, and system resolution is 0.15 μm/pixel, using megapixel camera technology.
The x,y system uses 0.1-μm linear glass scales and operates at a speed of 200 mm/s, using servo motors and smooth running cross-roller staging. The x,y stage can be configured with either square or round wafer substrate vacuum chuck as well as electrostatic chucks for thin polymer film materials. Additional load/unload modules are available for cassette-to-cassette operations and special handling options for reel-to-reel film material handling.