Patent ID: 6075334
Filing Date: 2000-06-13
Classification: H01L

Abstract:
In combination with a robot having an arm with a wafer holding wand at its outer end, motor means for moving said arm vertically in a Z axis, rotatably about the Z axis in an angle .theta. and for extending said wand radially along an R axis, a system for automatically controlling said robot to cause said wand to be positioned precisely within the opening of a fixed enclosure near said robot so that it can repetitively place a semiconductor wafer within or remove it from said enclosure, said system comprising;a machine controller having a memory and logic circuitry and connected to said robot, said controller having stored dimensional characteristics of said wand and said enclosure;an I/O component and a motor amplifier connected to said machine controller;first sensor means for producing signals to said controller for causing said robot wand to be moved to a vertical Z axis position relative to said enclosure opening; andsecond sensor means within said fixed enclosure for producing signals to said controller that cause said robot wand to move automatically in .theta. and R directions so as to arrive at a precise position within said fixed enclosure to thereby enable said wand to pick up or drop off a wafer at said precise position.