Imprint Lithography Apparatus and Method

Abstract

An imprint lithography apparatus is disclosed that includes an imprint template holder arranged to hold an imprint template, and a plurality of position sensors configured to measure change of the size and/or shape of the imprint template, wherein the position sensors are mechanically isolated from the imprint template. Also disclosed is a lithography method that includes using an imprint template to imprint a pattern onto a substrate, and measuring changes of the size and/or shape of the imprint template while imprinting the pattern onto the substrate.

1 . An imprint lithography apparatus comprising:
 an imprint template holder arranged to hold an imprint template; and   a plurality of position sensors configured to measure change of the size and/or shape of the imprint template, wherein the position sensors are mechanically isolated from the imprint template.   
     
     
         2 . The apparatus of  claim 1 , wherein the position sensors are configured to measure change of the positions of portions of the imprint template perimeter. 
     
     
         3 . The apparatus of  claim 1 , wherein the position sensors are configured to measure positions of sets of lines, the position sensors and the sets of lines acting as linear encoders. 
     
     
         4 . The apparatus of  claim 3 , wherein the sets of lines are provided in the perimeter of the imprint template. 
     
     
         5 . The apparatus of  claim 3 , wherein the sets of lines are provided on structures attached to the imprint template. 
     
     
         6 . The apparatus of  claim 3 , wherein the imprint template holder comprises a plurality of actuators provided around the perimeter of the imprint template, the actuators configured to apply force to the imprint template to change the size and/or shape of the imprint template, and wherein the sets of lines are provided on the actuators. 
     
     
         7 . The apparatus of  claim 1 , wherein the position sensors are configured to measure the positions of alignment marks provided in the perimeter of the imprint template. 
     
     
         8 . The apparatus of  claim 1 , wherein the imprint template holder comprises a plurality of actuators provided around the perimeter of the imprint template, the actuators configured to apply force to the imprint template to change the size and/or shape of the imprint template. 
     
     
         9 . The apparatus of  claim 8 , wherein the position sensors and the actuators together comprise a control loop configured to control the size and/or shape of the imprint template. 
     
     
         10 . The apparatus of  claim 8 , wherein the position sensors comprise an interferometer, the interferometer configured to direct a laser beam at a reflector which surrounds or substantially surrounds one of the plurality of actuators but is not in mechanical communication with that actuator. 
     
     
         11 . The apparatus of  claim 1 , comprising:
 a measurement module configured to measure the positions of alignment marks on a substrate provided on a first substrate table; and   an imprint module which comprises the imprint template holder, the plurality of position sensors and a second table,   wherein the apparatus is configured to move the first substrate table to the imprint module once the positions of the substrate alignment marks have been measured, and   the imprint module is configured to imprint a pattern onto the substrate at locations which are determined relative to the substrate alignment mark positions as measured by the measurement module.   
     
     
         12 . The apparatus of  claim 11 , wherein the first substrate table is provided with alignment marks, the measurement module is configured to measure the positions of the substrate alignment marks relative to the first substrate table alignment marks, and the imprint module further comprises an alignment apparatus which is configured to measure the position of the imprint template relative to the first substrate table alignment marks. 
     
     
         13 . The apparatus of  claim 11 , wherein the imprint module is configured to control the size and/or shape of the imprint template. 
     
     
         14 . The apparatus of  claim 11 , wherein the measurement module is one of a plurality of measurement modules. 
     
     
         15 . A lithography method comprising:
 using an imprint template to imprint a pattern onto a substrate; and   measuring changes of the size and/or shape of the imprint template while imprinting the pattern onto the substrate.   
     
     
         16 . The lithography method of  claim 15 , wherein the changes of the size and/or shape of the imprint template are measured using a plurality of position sensors which are mechanically isolated from the imprint template, the position sensors configured to measure changes of the positions of portions of the imprint template perimeter. 
     
     
         17 . The lithography method of  claim 15 , further comprising:
 using a measurement module to measure the positions of alignment marks on a substrate on a first substrate table;   moving the first substrate table to an imprint module which comprises the imprint template and a second table; and   imprinting a pattern onto the substrate at locations which are determined relative to the substrate alignment mark positions as measured by the measurement module, the changes of the size and/or shape of the imprint template being measured in the imprint module.   
     
     
         18 . The lithography method of  claim 17 , wherein the measurement module measures the positions of the substrate alignment marks relative to alignment marks provided on the substrate table, and the imprint module further comprises an alignment apparatus which is configured to measure the position of the imprint template relative to the substrate table alignment marks. 
     
     
         19 . The lithography method of  claim 17 , further comprising transferring the first substrate table from the imprint module to the measurement module after the pattern has been imprinted one or more times onto the substrate, measuring the position of the substrate relative to the substrate table, then transferring the first substrate table back to the imprint module, and then imprinting the pattern one or more times onto the substrate. 
     
     
         20 . An imprint lithography apparatus comprising:
 a measurement module configured to measure the positions of alignment marks on a substrate provided on a first substrate table; and   an imprint module which comprises an imprint template and a second table,   wherein the apparatus is configured to move the first substrate table to the imprint module once the positions of the substrate alignment marks have been measured, and   the imprint module is configured to imprint a pattern onto the substrate at locations which are determined relative to the substrate alignment mark positions as measured by the measurement module.