Wafer Chamber Position Sensing Without Opening the Chamber

The patent replaces mechanical visual inspection (opening the chamber) with an optical sensing system. Sensors mounted on the robot arm's end effector detect object positions through the chamber window or opening without requiring the chamber to be opened, substituting mechanical observation with optical detection to maintain temperature stability while obtaining position information

The patent introduces sensors as an intermediary between the observer and the objects inside the chamber. These sensors act as mediators that can detect object positions through the chamber boundary without requiring direct visual access by opening the chamber, thus preserving the thermal environment while providing position information

The patent divides the sensing system into separate functional components: sensors mounted on the end effector body, individual sealing lids for each sensor, and signal transmission pathways. This segmentation allows each sensor to be independently protected by its own sealing lid while maintaining detection capability, isolating the sensors from the harsh chamber environment (high temperature, plasma, vacuum) to ensure reliability

The patent uses sealing lids (which may be made of heat-resistant or transparent materials) to protect sensors from the chamber environment. These sealing structures act as protective barriers that allow optical or mechanical sensing to function while shielding the sensors from high temperature, plasma exposure, and vacuum conditions that would otherwise damage them