Adhesive for euv mask, cleaning method of the same, and reusing method of euv mask using the same

Abstract

An adhesive for an EUV mask includes an epoxy resin composition in an amount of 50 wt % to 80 wt % based on a total weight of the adhesive, the epoxy resin composition including an epoxy resin, a hardener, a toughening agent, a filler, and a curing accelerator, and an inorganic filler in an amount of 20 wt % to 50 wt % based on the total weight of the adhesive, the inorganic filler including one or more of aluminum hydroxide or calcium carbonate.

1 . An adhesive for an EUV mask, the adhesive comprising:
 an epoxy resin composition in an amount of 50 wt % to 80 wt % based on a total weight of the adhesive, the epoxy resin composition including an epoxy resin, a hardener, a toughening agent, a filler, and a curing accelerator; and   an inorganic filler in an amount of 20 wt % to 50 wt % based on the total weight of the adhesive, the inorganic filler including one or more of aluminum hydroxide or calcium carbonate.   
     
     
         2 . The adhesive as claimed in  claim 1 , wherein the inorganic filler further includes one or more of silica, alumina, barium sulfate, talc, clay, mica, magnesium hydroxide, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium dioxide, barium zirconate, or calcium zirconate. 
     
     
         3 . The adhesive as claimed in  claim 2 , wherein the inorganic filler has an average particle size of 0.1 μm to 10 μm. 
     
     
         4 . The adhesive as claimed in  claim 1 , wherein the epoxy resin composition includes:
 the epoxy resin in an amount of 15 wt % to 40 wt % based on a total weight of the epoxy resin composition,   the hardener in an amount of 40 wt % to 70 wt % based on the total weight of the epoxy resin composition,   the toughening agent in an amount of 7 wt % to 13 wt % based on the total weight of the epoxy resin composition,   the filler in an amount of 3 wt % to 7 wt % based on the total weight of the epoxy resin composition, and   the curing accelerator in an amount of 1 wt % to 5 wt % based on the total weight of the epoxy resin composition.   
     
     
         5 . The adhesive as claimed in  claim 4 , wherein the hardener includes one or more of an ether diamine, an aliphatic diamine, or an aromatic diamine. 
     
     
         6 . The adhesive as claimed in  claim 4 , wherein the epoxy resin includes one or more of a bisphenol A epoxy resin, a bisphenol F epoxy resin, or a novolac epoxy resin. 
     
     
         7 . The adhesive as claimed in  claim 4 , wherein the toughening agent includes a modified epoxy resin having a carboxyl group or an amine group as an end group. 
     
     
         8 . The adhesive as claimed in  claim 4 , wherein the filler in the epoxy resin composition includes one or more of amorphous silica, aluminum trihydrate, calcium carbonate, polystyrene beads, or polymethylmethacrylate beads. 
     
     
         9 . The adhesive as claimed in  claim 4 , wherein the curing accelerator includes one or more of a tertiary amine, a polyether amine, or imidazole. 
     
     
         10 . The adhesive as claimed in  claim 4 , wherein the epoxy resin composition has a thermosetting property. 
     
     
         11 . A method of removing an adhesive for EUV mask including an epoxy resin composition and an inorganic filler, the method comprising:
 swelling the adhesive on an EUV mask at a stud location by adding water to the adhesive to form a swollen adhesive, wherein swelling the adhesive includes an adsorption reaction in which the inorganic filler and the water are adsorbed to each other; and   removing the swollen adhesive by adding a strong acid to the swollen adhesive, wherein removing the swollen adhesive includes an acid-base reaction between the inorganic filler and the strong acid.   
     
     
         12 . The method as claimed in  claim 11 , wherein the water is deionized water. 
     
     
         13 . The method as claimed in  claim 11 , wherein the strong acid is sulfuric acid. 
     
     
         14 . The method as claimed in  claim 11 , wherein adding the water and adding the strong acid are simultaneously performed. 
     
     
         15 . The method as claimed in  claim 11 , wherein the adhesive includes:
 the epoxy resin composition in an amount of 50 wt % to 80 wt % based on a total weight of the adhesive, and   the inorganic filler in an amount of 20 wt % to 50 wt % based on the total weight of the adhesive.   
     
     
         16 . The method as claimed in  claim 11 , wherein the inorganic filler includes one or more of silica, alumina, barium sulfate, talc, clay, mica, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium dioxide, barium zirconate, and calcium zirconate. 
     
     
         17 . The method as claimed in  claim 16 , wherein the inorganic filler has an average particle size of 0.1 μm to 10 μm. 
     
     
         18 . The method as claimed in  claim 15 , wherein the epoxy resin composition includes:
 an epoxy resin in an amount of 15 wt % to 40 wt % based on a total weight of the epoxy resin composition,   a hardener in an amount of 40 wt % to 70 wt % based on the total weight of the epoxy resin composition,   a toughening agent in an amount of 7 wt % to 13 wt % based on the total weight of the epoxy resin composition,   a filler in an amount of 3 wt % to 7 wt % based on the total weight of the epoxy resin composition, and   a curing accelerator in an amount of 1 wt % to 5 wt % based on the total weight of the epoxy resin composition.   
     
     
         19 . A method of reusing an EUV mask, the method comprising:
 i) applying an adhesive on an EUV mask;   ii) attaching a stud on the adhesive for EUV mask;   iii) combining an EUV pellicle on the stud;   iv) separating the EUV pellicle from the stud;   v) detaching the stud from the EUV mask; and   vi) removing the adhesive from the EUV mask,   wherein operations i) to vi) are repeatedly performed.   
     
     
         20 . The method as claimed in  claim 19 , wherein vi) includes:
 swelling the adhesive by adding a water into the adhesive remaining on the EUV mask to form a swollen adhesive, and   removing the swollen adhesive by adding a strong acid to the swollen adhesive.   
     
     
         21 - 26 . (canceled)