Design and Implementation of a Robot Assisted Crucible Charging System

A robotic system is developed to automate the packing of polycrystalline silicon nuggets into a fragile fused silica crucible in CZ semiconductor wafer production. The highly irregular shapes of the nuggets make this a difficult and challenging task. In this system, nugget grasping is done with a three-cup suction gripper and nugget manipulation is attained with a 7 DOF SCARA manipulator. An optical 3-D vision system, based on active laser triangulation, measures nugget and crucible profiles. A model-free Virtual Trial and Error packing algorithm determines optimal nugget placement in real time. A hybrid position-force control scheme has been implemented and tested for physical nugget placement. The integrated system achieves high production rates, required precision and cost effectiveness.

• Type: Conference
• Year: 2000
• Where: ICRA
• Authors: Vivek A. Sujan, Steven Dubowsky, Yoshiaki Ohkami
• Keywords: Determines Optimal Nugget, ICRA 2000, Nugget Placement, Physical Nugget Placement, Robotics