Supercritical carbon dioxide/chemical formulation for removal of photoresists

Abstract

A photoresist cleaning composition for removing photoresist and ion implanted photoresist from semiconductor substrates. The cleaning composition contains supercritical CO 2 (SCCO2) and alcohol for use in removing photoresist that is not ion-implanted. When the photoresist has been subjected to ion implantation, the cleaning composition additionally contains a fluorine ion source. Such cleaning composition overcomes the intrinsic deficiency of SCCO2 as a cleaning reagent, viz., the non-polar character of SCCO2 and its associated inability to solubilize species such as inorganic salts and polar organic compounds that are present in the photoresist and that must be removed from the semiconductor substrate for efficient cleaning. The cleaning composition enables damage-free, residue-free cleaning of substrates having photoresist or ion implanted photoresist thereon.

1 - 41 . (canceled)  
   
   
       42 . A composition comprising supercritical carbon dioxide (SCCO 2 ), at least one alcohol, at least one fluorine source, and at least one implanted cation, wherein said cleaning composition is useful for removing ion-implanted photoresist from a microelectronic device having such material thereon.  
   
   
       43 . The composition of  claim 42 , wherein the at least one alcohol comprises at least one C 1 -C 4  alcohol.  
   
   
       44 . The composition of  claim 42 , wherein the at least one alcohol comprises methanol.  
   
   
       45 . The composition of  claim 42 , wherein the concentration of the at least one alcohol is from about 5 wt. % to about 20 wt. %, based on the total weight of the composition.  
   
   
       46 . The composition of  claim 42 , wherein said at least one fluorine ion source includes at least one fluorine source reagent selected from the group consisting of hydrogen fluoride (HF), amine trihydrogen fluoride compounds of the formula NR 3 (HF) 3  wherein each R is independently selected from hydrogen and lower alkyl, hydrogen fluoride-pyridine (pyr-HF), ammonium fluorides of the formula R 4 NF, wherein each R is independently selected from hydrogen and lower alkyl, other quaternary fluorides, xenon difluoride, and fluoromethane.  
   
   
       47 . The composition of  claim 42 , wherein the at least one fluorine ion source has a concentration of from about 0.01 wt. % to about 5 wt. %, based on the total weight of the composition.  
   
   
       48 . The composition of  claim 42 , wherein the at least one fluorine ion source comprises pyr-HF.  
   
   
       49 . The composition of  claim 42 , further comprising an oxidation inhibitor.  
   
   
       50 . The composition of  claim 49 , wherein the oxidation inhibitor comprises boric acid.  
   
   
       51 . The composition of  claim 42 , wherein said at least one implanted cation comprises a cation selected from the group consisting of a boron-containing cation, a phosphorus-containing cation and an arsenic-containing cation.  
   
   
       52 . A method of removing ion-implanted photoresist from a microelectronic device having same thereon, said method comprising contacting the ion-implanted photoresist with a cleaning composition for sufficient time and under sufficient contacting conditions to remove the ion-implanted photoresist from the microelectronic device having same thereon, wherein said cleaning composition comprises SCCO 2 , at least one alcohol, at least one fluorine source, and at least one implanted cation.  
   
   
       53 . The method of  claim 52 , wherein said contacting conditions comprise elevated pressure.  
   
   
       54 . The method of  claim 53 , wherein said elevated pressure comprises pressure in a range of from about 1000 to about 7500 psi.  
   
   
       55 . The method of  claim 52 , wherein said contacting conditions comprise elevated temperature.  
   
   
       56 . The method of  claim 55 , wherein said elevated temperature comprises temperature in a range of from about 35° C. to about 100° C.  
   
   
       57 . The method of  claim 52 , wherein said contacting time is in a range of from about 1 to about 30 minutes.  
   
   
       58 . The method of  claim 52 , wherein the at least one alcohol comprises at least one C 1 -C 4  alcohol, and wherein said at least one fluorine ion source includes at least one fluorine source reagent selected from the group consisting of hydrogen fluoride (HF), amine trihydrogen fluoride compounds of the formula NR 3 (HF) 3  wherein each R is independently selected from hydrogen and lower alkyl, hydrogen fluoride-pyridine (pyr-HF), ammonium fluorides of the formula R 4 NF, wherein each R is independently selected from hydrogen and lower alkyl, other quaternary fluorides, xenon difluoride, and fluoromethane.  
   
   
       59 . The method of  claim 52 , wherein the at least one fluorine ion source comprises pyr-HF.  
   
   
       60 . The method of  claim 52 , wherein the at least one alcohol source comprises methanol.  
   
   
       61 . The method of  claim 52 , wherein the concentration of the at least one alcohol is from about 5 wt. % to about 20 wt. %, based on the total weight of the composition, and wherein the at least one fluorine ion source has a concentration of from about 0.01 wt. % to about 5 wt. %, based on the total weight of the composition.  
   
   
       62 . The method of  claim 52 , wherein said at least one implanted cation comprises a cation selected from the group consisting of a boron-containing cation, a phosphorus-containing cation, and an arsenic-containing cation.  
   
   
       63 . A method of removing ion implanted photoresist from a substrate having same thereon, said method comprising contacting the ion-implanted photoresist with a cleaning composition comprising SCCO 2 , alcohol and a fluorine ion source, for sufficient time and under sufficient contacting conditions to remove the ion implanted photoresist from the substrate.  
   
   
       64 . A composition comprising supercritical carbon dioxide (SCCO 2 ), at least one alcohol, and a complex formed by reacting a fluorine ion source with implanted cations, wherein said cleaning composition is useful for removing ion-implanted photoresist from a microelectronic device having such material thereon.  
   
   
       65 . The composition of  claim 64 , wherein said implanted cations comprise a cation selected from the group consisting of a boron-containing cation, a phosphorus-containing cation and an arsenic-containing cation.