Importance

Loading Importance Indicators...

Abstract

A load-lock unit is disposed between first and second atmospheres, stores a wafer transferred from the first atmosphere, is blocked off from the first atmosphere, is thereafter set in the same atmosphere as or a similar atmosphere to the second atmosphere, and is opened to communicate with the second atmosphere in order to transfer the wafer to the second atmosphere. The load-lock unit includes a load-lock chamber, a storing device, disposed in the load-lock chamber, for storing a plurality of wafers vertically at a gap, a holding mechanism for holding one of the plurality of wafers stored in the storing device, a rotating mechanism for rotating the wafer held by the holding mechanism, and an error detecting device for detecting the positional error of the center of the wafer and an orientation error of the wafer on the basis of data obtained by radiating light on the wafer which is rotating.

Loading the Abstract Image...

First Claim