Aqueous fluoride compositions for cleaning semiconductor devices

Abstract

The present invention relates to dilute fluoride solutions and methods for cleaning plasma etch residue from semiconductor substrates including such dilute solutions. The compositions and methods according to the invention can advantageously provide both cleaning efficiency and material compatibility.

1 . A dilute aqueous cleaner and residue remover comprising:
 from 0.02% to 0.18% by weight of a fluoride-containing compound selected from the group consisting of ammonium fluoride, alkylammonium fluorides, ethanolamine fluoride, ammonium biflouride, alkylammonium bifluorides, or a mixture thereof;   from 20% to about 40% by weight water;   from 59% to 85% by weight total of an amide and an ether solvent,   from 0.2% to 5% by weight of an acid selected from sulfamic acid, phosphonic acid, a soluble phosphonic acid derivative, or mixture thereof; and   from 0.2% to 5% by weight of an alkanolamine.   
   
   
       2 . The dilute aqueous cleaner and residue remover of  claim 1 , comprising:
 from 0.02% to 0.18% by weight of a fluoride-containing compound selected from the group consisting of ammonium fluoride, alkylammonium fluorides, ethanolamine fluoride, ammonium biflouride, alkylammonium bifluorides, or a mixture thereof;   between about 14% and 35% water by weight between 10 and 40% of an amide;   between 20 and 59% of a glycol ether;   between 0.2% to 5% by weight of an acid selected from sulfamic acid, phosphonic acid, a soluble phosphonic acid derivative, or mixture thereof; and   between 0.2% to about 5% by weight of an alkanolamine.   wherein the pH is between 6 and 8.   
   
   
       3 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the acid is sulfamic acid. 
   
   
       4 . The dilute aqueous cleaner and residue remover of  claim 2  wherein the acid is sulfamic acid. 
   
   
       5 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the acid is phosphonic acid and at least one of amino tris methylenephosphonic acid, ethylenediamine tetra methylenephosphonic acid, hexamethylenediamine tetra methylenephosphonic acid, diethylenetriamine penta methylenephosphonic acid, and 1-Hydroxy ethane diphosphonic acid. 
   
   
       6 . The dilute aqueous cleaner and residue remover of  claim 2  wherein the acid is phosphonic acid and at least one of amino tris methylenephosphonic acid, ethylenediamine tetra methylenephosphonic acid, hexamethylenediaamine tetra methylenephosphonic acid, diethylenetriamine penta methylenephosphonic acid, and 1-Hydroxy ethane diphosphonic acid. 
   
   
       7 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the acid comprises phosphonic acid. 
   
   
       8 . The dilute aqueous cleaner and residue remover of  claim 2  wherein the acid is comprises phosphonic acid. 
   
   
       9 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the amide comprises N,N-Dimethylacetamide and the ether comprises Diethylene glycol monobutyl ether. 
   
   
       10 . The dilute aqueous cleaner and residue remover of  claim 2  wherein the amide comprises N,N-Dimethylacetamide and the ether comprises Diethylene glycol monobutyl ether. 
   
   
       11 . The dilute aqueous cleaner and residue remover of  claim 4  wherein the amide comprises N,N-Dimethylacetamide and the ether comprises Diethylene glycol monobutyl ether. 
   
   
       12 . The dilute aqueous cleaner and residue remover of  claim 11  comprising between 0.06 and 0.18% of ammonium fluoride. 
   
   
       13 . The dilute aqueous cleaner and residue remover of  claim 1  comprising between 0.06 and 0.15% of ammonium fluoride. 
   
   
       14 . The dilute aqueous cleaner and residue remover of  claim 1  further comprising between 0.01 and 0.1% of a chelator. 
   
   
       15 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the pH is between 7 and 8. 
   
   
       16 . The dilute aqueous cleaner and residue remover of  claim 2  wherein the pH is between 7 and 8. 
   
   
       17 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the pH is between 7.2 and 7.8. 
   
   
       18 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the amide is selected from N-alkylacetamide, N,N-Dialkylacetamide, or mixture thereof where the alkyl moieties are independently methyl- or ethyl-, and wherein the ether is selected from Diethylene glycol monobutyl ether, Diethylene glycol monopropyl ether, or mixture thereof. 
   
   
       19 . The dilute aqueous cleaner and residue remover of  claim 1  wherein the alkanolamine is an N-alkyl-substituted ethanolamine, an N,N-dialkyl-substituted ethanol amine, where the alkyl moieties are independently methyl- or ethyl-, or mixture thereof. 
   
   
       20 . The dilute aqueous cleaner and residue remover of  claim 3  wherein the alkanolamine is an N-alkyl-substituted ethanolamine, an N,N-dialkyl-substituted ethanolamine, where the alkyl moieties are independently methyl- or ethyl-, or mixture thereof. 
   
   
       21 . The dilute aqueous cleaner and residue remover of  claim 1  comprising between 20 and 30% of an amide, and between 40 and 55% of a glycol ether. 
   
   
       22 . The dilute aqueous cleaner and residue remover of  claim 4  wherein the pH is between 7 and 8. 
   
   
       23 . The dilute aqueous cleaner and residue remover of  claim 4  wherein the pH is between 7.2 and 7.8, and wherein the alkanolamine is an N-alkyl-substituted ethanolamine, an N,N-dialkyl-substituted ethanolamine, where the alkyl moieties are independently methyl- or ethyl-, or mixture thereof. 
   
   
       24 . A dilute aqueous cleaner and residue remover consisting essentially of:
 between 0.5% and 1% of ammonium bifluoride, ammonium fluoride, or mixture thereof, between about 55% and 75% of one or more amide solvent;   water;   optionally between 0.001 and 0.5% of a chelator, and   
     an alkanolamine in an amount sufficient to have a pH of between 8 and 8.2. 
   
   
       25 . A dilute aqueous cleaner and residue remover comprising:
 between 0.5% and 1% of ammonium bifluoride, ammonium fluoride, or mixture thereof, between about 55 and 75% of one or more amide solvents;   water; and   one or more amines in an amount sufficient to have a pH of between 8 and 8.2.   
   
   
       26 - 33 . (canceled)