Dual scara arm

Abstract

A substrate transport apparatus having a drive section and a scara arm operably connected to the drive section to move the scara arm. The scara arm has an upper arm and at least one forearm. The forearm is movably mounted to the upper arm and capable of holding a substrate thereon. The upper arm is substantially rigid and is adjustable for changing a predetermined dimension of the upper arm.

What is claimed is: 
     
         1 . A substrate transport apparatus comprising:
 a drive section;   a scara arm operably connected to the drive section to move the scara arm through a range of motion, the scara arm comprising:
 an upper arm with a first arm section and a second arm section coupled to each other disposed at a predetermined steady state inclusive angle relative to each other persistent throughout the range of motion of the transport apparatus from retracted to extension at each destination of the transport apparatus; and more than one different forearms, each rotatably joined respectively at a rotatable joint to the upper arm wherein the first arm section has at least one forearm of the more than one different forearms rotatably joined to the first arm section at an end of the upper arm, and the second arm section has at least another forearm of the more than one different forearms rotatably joined to the second arm section at an opposite end of the upper arm; and 
   wherein the drive section has more than three independent drive axis, at least one drive axis, of the more than three independent drive axis, being coupled to and effecting movement of the upper arm, and each other drive axis, of the more than three independent drive axis, being respectively coupled to and effecting independent movement of each respective forearm of the more than one different forearms rotatably jointed to the upper arm defining the range of motion of the transport apparatus.   
     
     
         2 . The substrate transport apparatus of  claim 1 , wherein the rotatable joint of the at least one forearm and first arm section form an elbow joint at the end of the upper arm, and the rotatable joint of the at least another forearm and the second arm section form another elbow joint at the opposite end of the upper arm, and the elbow joint and the other elbow joint couple each of the more than one different forearms to respective ends of the upper arm. 
     
     
         3 . The substrate transport apparatus of  claim 1 , wherein each of the more than one different forearms has a batch end effector. 
     
     
         4 . The substrate transport apparatus of  claim 3 , further comprising a controller connected to the drive section, the controller configured to effect adjustment of each batch end effector along an extension and retraction path, relative to a respective substrate holding location at each destination of the transport apparatus, depending on a position of the first arm section relative to the second arm section. 
     
     
         5 . The substrate transport apparatus of  claim 4 , wherein the controller is configured to rotate the upper arm to effect the adjustment of each batch end effector along the extension and retraction path. 
     
     
         6 . The substrate transport apparatus of  claim 3 , wherein each of the more than one different forearms with the batch end effector is disposed relative to one another so as to enter simultaneously into a port of a substrate holding station. 
     
     
         7 . The substrate transport apparatus of  claim 1 , wherein one of the more than one different forearms has a batch end effector and another of the more than one different forearms has an end effector with a different capacity than the batch end effector of the one of the more than one different forearms. 
     
     
         8 . The substrate transport apparatus of  claim 7 , wherein the one of the more than one different forearms is configured such that the batch end effector is swappable with the end effector with the different capacity. 
     
     
         9 . The substrate transport apparatus of  claim 7 , wherein the at least another forearm of the more than one different forearms is configured such that the end effector with the different capacity is swappable with the batch end effector. 
     
     
         10 . The substrate transport apparatus of  claim 1 , wherein the scara arm, having a batch end effector, is configured to provide the transport apparatus with a minimum footprint. 
     
     
         11 . A method for operating a transport apparatus, the method comprising:
 providing a drive section having more than three independent drive axis;   providing a scara arm operably connected to the drive section to move the scara arm through a range of motion, the scara arm including:
 an upper arm with a first arm section and a second arm section coupled to each other disposed at a predetermined steady state inclusive angle relative to each other persistent throughout the range of motion of the transport apparatus from retracted to extension at each destination of the transport apparatus; and more than one different forearms, each rotatably joined at a respective rotatable joint to the upper arm wherein the first arm section has at least one forearm of the more than one different forearms rotatably joined to the first arm section at an end of the upper arm, and the second arm section has at least another forearm of the more than one different forearms rotatably joined to the second arm section at an opposite end of the upper arm; 
   effecting movement of the upper arm with at least one drive axis of the more than three independent drive axis coupled to the upper arm; and   effecting independent movement of each respective forearm of the more than one different forearms with each other drive axis of the more than three independent drive axis coupled to each respective forearm, each respective forearm rotatably jointed to the upper arm defining the range of motion of the transport apparatus.   
     
     
         12 . The method of  claim 11 , wherein the rotatable joint of the at least one forearm and first arm section form an elbow joint at the end of the upper arm, and the rotatable joint of the at least another forearm and the second arm section form another elbow joint at the opposite end of the upper arm, and the elbow joint and the other elbow joint couple each of the more than one different forearms to respective ends of the upper arm. 
     
     
         13 . The method of  claim 11 , wherein each of the more than one different forearms has a batch end effector. 
     
     
         14 . The method of  claim 13 , further comprising effecting, with a controller connected to the drive section, adjustment of each batch end effector along an extension and retraction path, relative to a respective substrate holding location at each destination of the transport apparatus, depending on a position of the first arm section relative to the second arm section. 
     
     
         15 . The method of  claim 14 , further comprising rotating the upper arm, with the controller, to effect the adjustment of each batch end effector along the extension and retraction path. 
     
     
         16 . The method of  claim 13 , wherein each of the more than one different forearms with the batch end effector is disposed relative to one another so as to enter simultaneously into a port. 
     
     
         17 . The method of  claim 11 , wherein one of the more than one different forearms has a batch end effector and another of the more than one different forearms has an end effector with a different capacity than the batch end effector of the one of the more than one different forearms. 
     
     
         18 . The method of  claim 17 , further comprising swapping the batch end effector of the one of the more than one different forearms with the end effector with the different capacity. 
     
     
         19 . The method of  claim 17 , further comprising swapping the end effector with the different capacity of the another of the more than one different forearms with the batch end effector. 
     
     
         20 . The method of  claim 11 , wherein the scara arm, having a batch end effector, is configured to provide the transport apparatus with a minimum footprint with a batch end effector.