Wafer processing apparatus capable of mapping wafers

Abstract

A wafer processing apparatus on which a pod having an opening is detachably mounted is provided with a door unit and a mapping unit provided with a transmitting type sensor having an emitter and a detector forming a slot therebetween. The emitter and the detector are moved toward the opening in the pod and are plunged into the interior of the pod after a door is opened by the door unit, and the slot between the emitter and the detector crosses an end portion of a wafer to thereby detect the presence or absence of the wafer. Thereby, a mechanism portion liable to produce dust which may adhere to the wafer and cause the contamination thereof can be disposed separately from the pod.

What is claimed is:  
     
         1 . A wafer mapping apparatus for determining whether a wafer is present or not on each of shelves when a pod having a box which has an opening and the shelves for taking custody of the wafer in parallel along a vertical direction and a lid separably covering said opening is fixed to a wafer processing apparatus, said wafer mapping apparatus comprising: 
 a first sensor for determining whether the wafer is present or not on shelves;    a mapping frame for supporting said first sensor; a movable portion for supporting said first sensor movable in the vertical direction through said mapping frame in a state in which said sensor is plunged into said box;    a timing plate having index means disposed at predetermined intervals; and    second sensors provided so as to sandwich said index means therebetween,    wherein a signal in response to each of said shelves is generated by said timing plate and said second sensor in accordance with a vertical movement of said sensor.    
     
     
         2 . A wafer mapping apparatus according to  claim 1 , wherein said movable portion and said second sensors are located underside of lower edge of said opening, and are provided within a substantially closed space.  
     
     
         3 . A wafer mapping apparatus according to  claim 1 , wherein said movable portion is connected with a door which holds said lid of said pod, apart said lid from said box, and moves said lid substantially below said box.  
     
     
         4 . A wafer mapping apparatus according to  claim 2 , wherein said movable portion is connected with a door which holds said lid of said pod, apart said lid from said box, and moves said lid substantially below said box.  
     
     
         5 . A wafer mapping apparatus according to  claim 1 , wherein said mapping frame is tilted so that the upper side thereof is apart from a plane forming said opening of said pod in a state that said opening is closed bys said lid, and said sensor is plunged into said box after said opening is opened.  
     
     
         6 . A wafer mapping apparatus according to  claim 2 , wherein said mapping frame is tilted so that the upper side thereof is apart from a plane forming said opening of said pod in a state that said opening is closed bys said lid, and said sensor is plunged into said box after said opening is opened.  
     
     
         7 . A wafer mapping apparatus according to  claim 3 , wherein said mapping frame is tilted so that the upper side thereof is apart from a plane forming said opening of said pod in a state that said opening is closed bys said lid, and said sensor is plunged into said box after said opening is opened.