Method and apparatus for treating substrate

Abstract

The inventive concept provides a method for treating a substrate. In an embodiment, the substrate treating method includes a treatment step of treating a residue on the substrate with a first fluid in a supercritical state and a second fluid in a supercritical state in a process space of a chamber, and the first fluid in the supercritical state and the second fluid in the supercritical state have different densities.

What is claimed is: 
     
         1 . A method for treating a substrate, the method comprising:
 a treatment step of treating a residue on the substrate with a first fluid in a supercritical state and a second fluid in a supercritical state in a process space of a chamber,   wherein the first fluid in the supercritical state and the second fluid in the supercritical state have different densities.   
     
     
         2 . The method of  claim 1 , wherein a supply step of supplying the first fluid into the process space and an exhaust step of evacuating the process space are sequentially repeated a plurality of times in the treatment step, and
 wherein the second fluid is supplied in the supply step.   
     
     
         3 . The method of  claim 1 , wherein a supply step of supplying the first fluid into the process space and an exhaust step of evacuating the process space are sequentially repeated a plurality of times in the treatment step, and
 wherein the second fluid is supplied in the supply step and the exhaust step.   
     
     
         4 . The method of  claim 1 , wherein the method further comprises a depressurization step of reducing pressure in the process space by evacuating the process space after the treatment step, and
 wherein the second fluid is supplied into the process space during the depressurization step.   
     
     
         5 . The method of  claim 1 , wherein the method further comprises an opening step of opening the chamber after the depressurization step, and
 wherein the second fluid in a gaseous state is supplied into the process space during the opening step.   
     
     
         6 . The method of  claim 1 , wherein a supply step of supplying the first fluid or the second fluid and an exhaust step of evacuating the process space after the supply step are alternately performed a plurality of times in the treatment step, and
 wherein the supply step includes a first supply step of supplying only the first fluid and a second supply step of supplying only the second fluid.   
     
     
         7 . The method of  claim 6 , wherein an amount of the first fluid supplied per unit time in the first supply step is the same as an amount of the second fluid supplied per unit time in the second supply step. 
     
     
         8 . The method of  claim 7 , wherein the first supply step is continuously performed N times, and the second supply step is continuously performed M times, N being a number larger than M. 
     
     
         9 . The method of  claim 8 , wherein as the number of times that the supply step is repeated increases, N gradually decreases and M gradually increases. 
     
     
         10 . The method of  claim 6 , wherein the first supply step and the second supply step are alternately performed, and
 wherein an amount of the first fluid supplied per unit time in the first supply step is larger than an amount of the second fluid supplied per unit time in the second supply step.   
     
     
         11 . The method of  claim 10 , wherein as the number of times that the supply step is repeated increases, the amount of the first fluid supplied per unit time in the first supply step decreases, and the amount of the second fluid supplied per unit time increases. 
     
     
         12 . The method of  claim 6 , wherein a total amount of the first fluid supplied is larger than a total amount of the second fluid supplied. 
     
     
         13 . The method of  claim 1 , wherein the treatment of the substrate is a process of removing an organic solvent on the substrate by dissolving the organic solvent on the substrate in the first fluid or the second fluid. 
     
     
         14 . The method of  claim 1 , wherein the first fluid has a higher density than the second fluid, and the second fluid has a higher diffusivity than the first fluid. 
     
     
         15 . The method of  claim 1 , wherein the first fluid is a fluid configured to dissolve the residue better than the second fluid. 
     
     
         16 . The method of  claim 1 , wherein the second fluid is a fluid configured to experience a phase change into a supercritical state at a lower temperature and a lower pressure than the first fluid. 
     
     
         17 . The method of  claim 1 , wherein the second fluid is supplied at a temperature and pressure above a temperature and pressure at which the first fluid experiences a phase change into a supercritical state. 
     
     
         18 . The method of  claim 1 , wherein the first fluid is carbon dioxide, and the second fluid is an inert gas. 
     
     
         19 . The method of  claim 1 , wherein the second fluid is an argon gas, a nitrogen gas, or a helium gas. 
     
     
         20 . The method of  claim 1 , wherein the first fluid and the second fluid are the same types of fluids having different densities.