Patent ID: 7618226
Filing Date: 2009-11-17
Classification: H01L

Abstract:
1. A semiconductor substrate transfer apparatus for transferring semiconductor substrates from a first container to a second container, comprising: multiple end effectors for unloading substrates from the first container and loading the substrates to the second container, one of said multiple end effectors being configured to hold at least one substrate, another of said multiple end effectors being configured to hold more substrates than the one of said multiple end effectors; at least one robot arm for moving the multiple end effectors from the first container to the second container, wherein the at least one robot arm comprises a first arm and a second arm wherein the one of said multiple end effectors and the another of said multiple end effectors have a common axis disposed therein and are co-axially and rotatably joined at the common axis with the second arm which is rotatably joined with the first arm, and the first arm has a support axis rotatably fixed to a base and common to the one of said multiple end effectors and the another of said multiple end effectors, wherein the one of the multiple end effectors and the another of the multiple end effectors are independently rotatable at the common axis with respect to the second arm; a controller for judging which end effector or end effectors in the multiple end effectors are to be selected based on a distribution status of substrates stored in the first and second containers and for rotating the selected end effector(s) for unloading a substrate or substrates from the first container and loading the substrate or substrates to the second container; and a sensor device for sensing an occupancy status of slots of the first container, which is used as the distribution status by the controller, wherein the sensor device is installed in a door of the first container and is configured to sense the occupancy status of slots when the door opens.