Method and system for dispensing resist solution

Abstract

An apparatus and method for dispensing a solution on a substrate is described in which the solution is dispensed through a solution nozzle assembly while the substrate is rotated. As the solution is dispensed, the solution on the substrate forms a wave front that radially spreads from the substrate center to the substrate edge. The dispensing of the solution is performed in such a way that the solution is dispensed at a radial location substantially equivalent to or less than the radial location of the wave front at any instant in time.

1 . A method of dispensing a solution on a substrate comprising:
 rotating said substrate;   translating a nozzle from the center of said substrate towards a peripheral edge of said substrate;   dispensing said solution from said nozzle on said substrate during said translating in order to form a wave front that spreads radially across the upper surface of said substrate, wherein said solution initially dispenses at the center of said substrate and progresses to dispense at a radial location away from the center of said substrate;   adjusting a rotation rate for said rotating during said dispensing;   terminating said dispensing of said solution; and   terminating said rotating of said substrate.   
     
     
         2 . The method of  claim 1 , wherein said solution comprises a 248 nm (nanometer) photo-resist solution, a 193 nm photo-resist solution, a 157 nm photo-resist solution, an EUV (extreme ultraviolet) photo-resist solution, an anti-reflective coating solution, a low dielectric coating solution, and a top coat solution. 
     
     
         3 . The method of  claim 1 , wherein said translating said nozzle is such that said radial location of said dispensing is substantially equivalent to or less than a radial position of said wave front at any instant in time. 
     
     
         4 . The method of  claim 1 , further comprising:
 adjusting a radial translation rate of said nozzle.   
     
     
         5 . The method of  claim 1 , further comprising:
 adjusting a dispensing rate of said solution.   
     
     
         6 . The method of  claim 1 , wherein said adjusting said rotation rate is performed in accordance with a process recipe, a simulation of said dispensing, or feedback from a diagnostic system, or any combination of two or more thereof. 
     
     
         7 . The method of  claim 1 , further comprising:
 setting a process recipe in order to achieve said dispensing, wherein said process recipe is designed for a total volume of said solution to dispense, and said process recipe includes a dispensing rate from said nozzle, said rotation rate for said substrate rotation, and a radial translation rate of said nozzle.   
     
     
         8 . The method of  claim 1 , wherein said nozzle is configured to provide said dispensing at said radial location ranging from approximately 25% to 100% of a radial position of said wave front. 
     
     
         9 . The method of  claim 1 , wherein said nozzle is configured to provide said dispensing at said radial location ranging from approximately 50% to 100% of a radial position of said wave front. 
     
     
         10 . The method of  claim 1 , wherein said nozzle is configured to provide said dispensing at said radial location ranging from approximately 90% to 100% of a radial position of said wave front. 
     
     
         11 . The method of  claim 1 , wherein said nozzle is configured to provide said dispensing at said radial location that is substantially equivalent to a radial position of said wave front. 
     
     
         12 . The method of  claim 1 , wherein said dispensing translates radially at a translation rate substantially equivalent to or less than a speed of said wave front. 
     
     
         13 . The method of  claim 12 , wherein said translation rate ranges from approximately 25% to 100% of said speed of said wave front. 
     
     
         14 . The method of  claim 12 , wherein said translation rate ranges from approximately 90% to 100% of said speed of said wave front. 
     
     
         15 . A method of dispensing a solution on a substrate comprising:
 selecting a process recipe comprising one or more process parameters for dispensing said solution, said one or more process parameters including a dispensing rate of said solution as a function of time, a rotation rate of said substrate as a function of time, and a translation rate of a nozzle for dispensing said solution as a function of time;   rotating said substrate;   translating said nozzle from the center of said substrate towards a peripheral edge of said substrate;   dispensing said solution from said nozzle on said substrate in order to form a wave front that spreads radially across the upper surface of said substrate, wherein said solution initially dispenses at the center of said substrate and progresses to dispense at a radial location of said substrate away from the center; and   adjusting said dispensing, said rotating, and said translating according to said process recipe.   
     
     
         16 . The method of  claim 15 , further comprising:
 measuring a position of said wave front, a speed of said wave front, or a state of said wave front, or any combination of two or more thereof; and   updating any one of said process parameters using said measuring.   
     
     
         17 . A method of dispensing a solution on a substrate comprising:
 rotating said substrate;   translating a nozzle from the center of said substrate towards a peripheral edge of said substrate;   dispensing said solution from said nozzle on said substrate in order to form a wave front that spreads radially across the upper surface of said substrate, wherein said solution initially dispenses at the center of said substrate, and progresses to dispense at a radial location away from the center;   controlling a shape of said wave front;   terminating said dispensing of said solution; and   terminating said rotating of said substrate.   
     
     
         18 . The method of  claim 17 , wherein said controlling comprises performing any combination of one or more of the following:
 adjusting a rotation rate for said rotating;   adjusting a radial translation rate of the nozzle; or   adjusting a dispensing rate of said solution.   
     
     
         19 . A coating system for dispensing a solution on a substrate, comprising:
 a coating chamber;   a substrate holder coupled to said coating chamber and configured to support said substrate;   a drive unit coupled to said substrate holder and configured to rotate said substrate holder;   a nozzle coupled to said coating chamber and configured to dispense said solution on said substrate to form a wave front that spreads radially across the upper surface of said substrate;   a translation drive system coupled to said nozzle and configured to translate said nozzle from the center of said substrate towards a peripheral edge of said substrate;   a solution supply system coupled to said nozzle and configured to supply said nozzle with said solution; and   a controller coupled to said drive unit, said translation drive system, and said solution supply system, and configured to controllably adjust a rotation rate for rotating said substrate holder, or a translation rate for translating said nozzle, or a combination thereof.   
     
     
         20 . The coating system of  claim 19 , wherein said controller is further configured to controllably adjust a dispensing rate for dispensing said solution from said nozzle. 
     
     
         21 . A computer-readable medium encoded with a computer program, wherein the program, when executed by a processor, causes the processor to perform a method comprising:
 rotating said substrate;   translating a nozzle from the center of said substrate towards a peripheral edge of said substrate;   dispensing said solution from said nozzle on said substrate during said translating in order to form a wave front that spreads radially across the upper surface of said substrate, wherein said solution initially dispenses at the center of said substrate and progresses to dispense at a radial location away from the center of said substrate;   adjusting a rotation rate for said rotating during said dispensing;   terminating said dispensing of said solution; and   terminating said rotating of said substrate.