Apparatus and methods for a mask inverter

Abstract

In some embodiments, apparatus and methods are provided for improved handling of lithography masks including a mask inverter that includes a first contact pad dedicated to inverting masks that have not been cleaned; a second contact pad dedicated to inverting masks that have been cleaned; an actuator coupled to the first and second contact pads and operable to invert the first and second contact pads; and a controller coupled to the actuator and operative to control the actuator. Numerous other aspects are provided.

The invention claimed is: 
     
         1 . A system for handling masks comprising:
 a first load port;   an atmospheric dual blade robot operable to access a first carrier in the first load port;   a mask inverter including two contact pads and disposed to receive masks from the atmospheric dual blade robot; and   a mask cleaning system disposed to receive masks from the atmospheric dual blade robot.   
     
     
         2 . The system of  claim 1  wherein the system for handling masks is operative to handle masks that have not been cleaned with a first set of end effectors and contact pads, and
 wherein the system for handling masks is operative to handle masks that have been cleaned with a second set of end effectors and contact pads. 
 
     
     
         3 . The system of  claim 1  wherein the mask inverter includes:
 a first contact pad dedicated to inverting masks that have not been cleaned; 
 a second contact pad dedicated to inverting masks that have been cleaned; 
 an actuator coupled to the first and second contact pads and operable to invert the first and second contact pads; and 
 a controller coupled to the actuator and operative to control the actuator. 
 
     
     
         4 . The system of  claim 3  wherein the first and second contact pads each include a chuck to hold a mask. 
     
     
         5 . The system of  claim 4  wherein the chucks are electro-static chucks. 
     
     
         6 . The system of  claim 3  wherein the first and second contact pads each include a sensor for detecting a mask on the contact pads. 
     
     
         7 . The system of  claim 6  wherein the sensors are coupled to the controller and operable to detect an orientation of a mask on the contact pads. 
     
     
         8 . The system of  claim 6  wherein the sensors are coupled to the controller and operable to detect misalignment of a mask on the contact pads. 
     
     
         9 . The system of  claim 3  wherein the actuator is operable to invert the contact pads independently of each other. 
     
     
         10 . A method of handling masks comprising:
 loading a mask onto a first contact pad of a mask inverter using a first end effector;   inverting the mask using the first contact pad;   unloading the mask from the mask inverter using the first end effector;   cleaning the mask;   loading the mask onto a second contact pad of the mask inverter using a second end effector;   inverting the mask using the second contact pad; and   unloading the mask from the mask inverter using the second end effector.   
     
     
         11 . The method of  claim 10  wherein loading the mask onto a first contact pad includes securing the mask to the first contact pad via a first chuck, and
 wherein loading the mask onto a second contact pad includes securing the mask to the second contact pad via a second chuck. 
 
     
     
         12 . The method of  claim 10  wherein loading the mask onto a first contact pad includes detecting the mask on the first contact pad using a first sensor, and
 wherein loading the mask onto a second contact pad includes detecting the mask on the second contact pad using a second sensor. 
 
     
     
         13 . The method of  claim 10  wherein loading the mask onto a first contact pad includes transferring the mask from a first load port, and
 wherein unloading the mask from the mask inverter includes transferring the mask from the second contact pad to a second load port.