Patent ID: 8462009

Claim:
A device for use with a process chamber for processing substrates, the device comprising: a gate valve sensor configured to sense a position of a gate valve that opens and closes an opening in the process chamber and to output a first signal; a determination device configured to receive the first signal from the gate valve sensor, to determine whether the gate valve is in an opened or a closed position relative to the opening in the process chamber, and to output a second signal; and a notification device configured to receive the second signal from the determination device and to provide at least one of a visual or an audible indication of the position of the gate valve, wherein the gate valve sensor comprises a light emitting sensor and a light receiving sensor, wherein the light emitting sensor and the light receiving sensor are installed opposite each other, with one of the light emitting sensor or the light receiving sensor installed on the gate valve, and the other installed on a guide positioned at least partially in the process chamber, wherein the guide is configured to guide movement of a transfer robot into and out of the process chamber.