Enhance repeatability

Fabworx robots have improved wafer placement repeatability in the process modules, reducing backside pressure faults and improving process capabilities. 

Non-repeatability of wafer placement in the robot is caused by several items:

  • Wafers readily slide on the metallic end effector.
  • Wrist pivots have significant backlash.
  • Elbow joints are loose.
  • Hub magnet rings are not held firmly in place.
  • Upper and lower motors can twist and rock.
  • Blade leveling is performed at the hub by adjusting the entire arm.

Fabworx robot designs address the root causes of each issue:

  • End effectors with a patented o-ring design eliminate wafer sliding.
  • Pivots are replaced with patented zero-backlash interlocking wrist bands.
  • The elbow bearing joint is stiff and smooth.
  • Increased spring spacer force keeps magnet rings aligned and smooth (in the 200mm hub).
  • Brackets lock down upper and lower motors (in the 200mm hub).
  • Blade leveling is performed quickly and repeatably at the wrist.

Fabworx arm assemblies are exceptionally tight to eliminate extraneous movement. With reduced backlash and the associated vibrations, wafer sliding on the end effector is eliminated and better wafer placement repeatability is attained. Increased wafer placement repeatability results in a reduction in backside pressure faults and associated chamber downtime. This is especially valuable in placement-sensitive processes like CVD Tungsten, and in chambers that employ electro-static chucks.