Method and precursors for producing oxostannate rich films

Abstract

A method for forming a fluorinated oxostannate film involves vaporizing a volatile fluorinated alkyltin compound having at least two hydrolytically sensitive functional groups or at least two reactive functional groups which are sensitive to oxidation at a temperature greater than 200° C.; providing a substrate; physisorbing or chemisorbing the fluorinated alkyltin compound onto the substrate; and exposing the physisorbed or chemisorbed fluorinated alkyltin compound to a sequence of hydrolysis, irradiation, and/or oxidation steps to form the fluorinated oxostannate thin film on the substrate. Fluorinated alkyltin compounds having formula (I) are also described, in which R f is a fluorinated or partially fluorinated linear or branched alkyl group having about 1 to about 5 carbon atoms, X is a dialkylamino group having about 1 to about 4 carbon atoms, and n is 1 or 2: (R f CH 2 ) n SnX (4-n)   (I)

We claim: 
     
         1 . A method for forming a fluorinated oxostannate film comprising:
 vaporizing a volatile fluorinated alkyltin compound having at least two hydrolytically sensitive functional groups or at least two reactive functional groups which are sensitive to oxidation at a temperature greater than 200° C.;   providing a substrate;   physisorbing or chemisorbing the fluorinated alkyltin compound onto the substrate; and   exposing the physisorbed or chemisorbed fluorinated alkyltin compound to a sequence of hydrolysis and irradiation steps followed by an oxidation or second hydrolytic exposure to form the fluorinated oxostannate thin film on the substrate.   
     
     
         2 . The method according to  claim 1 , wherein the fluorinated alkyltin compound has formula (I):
   (R f CH 2 ) n SnX (4-n)   (I)
   
       wherein R f  is a fluorinated or partially fluorinated linear or branched alkyl group having about 1 to about 6 carbon atoms, X is a hydrolytically or oxidatively unstable group, and n is 1 or 2. 
     
     
         3 . The method according to  claim 2 , wherein R f  is a fluorinated or partially fluorinated ethyl group. 
     
     
         4 . The method according to  claim 2 , wherein each X is independently selected from a dialkylamino group having about 1 to about 4 carbon atoms and a halogen group. 
     
     
         5 . The method according to  claim 4 , wherein X is a dimethylamino group, a diethylamino group, a diisopropylamino group, or a methylethylamino group. 
     
     
         6 . The method according to  claim 4 , wherein X, Cl, Br, or H. 
     
     
         7 . The method according to  claim 1 , wherein the fluorinated alkyltin compound is 3,3,3-trifluoropropyltris(dimethylamino)tin; 3,3,3-trifluoropropyltrichlorotin; 3,3,3-trifluoropropyltriphenyltin; 3,3,3-trifluoropropyltris(diethylamino)tin; 3,3,3-trifluoropropyltris(diisopropylamino)tin; 3,3,3-trifluoropropyltris(methylethylamino)tin; 2,2,2-trifluoroethyltrichlorotin; or 6,6,6,5,5,4,4,3,3-nonafluorobutyltrichlorotin. 
     
     
         8 . A method for forming a patterned film comprising preparing the fluorinated oxostannate thin film according to  claim 1  and exposing the film to non-continuous radiation by rastering with an electron beam or laser or lithographic masking. 
     
     
         9 . A method for forming a continuous film comprising preparing the fluorinated oxostannate thin film according to  claim 1  and exposing the film to blanket exposure utilizing a suitable lithographic mask to provide optically clear fluorine doped tin oxide conductive film. 
     
     
         10 . A fluorinated alkyltin compound having formula (I):
   (R f CH 2 ) n Sn (4-n)   (I)
   
       wherein R f  is a fluorinated or partially fluorinated linear or branched alkyl group having about 1 to about 5 carbon atoms, X is a dialkylamino group having about 1 to about 4 carbon atoms, and n is 1 or 2. 
     
     
         11 . The fluorinated alkyltin compound according to  claim 10 , wherein the compound is 3,3,3-trifluoropropyltris(dimethylamino)tin; 3,3,3-trifluoropropyltris(diethylamino)tin; 3,3,3-trifluoropropyltris(diisopropylamino)tin; or 3,3,3-trifluoropropyltris(methylethylamino)tin. 
     
     
         12 . A two-component deposition mixture comprising: (a) a volatile fluorinated monoalkyltin compound having at least two hydrolytically sensitive functional groups or at least two reactive functional groups which are sensitive to oxidation at a temperature greater than 200° C.; and (b) a fluorinated dialkyltin compound, wherein the fluorinated alkyl group in the monoalkyltin compound is the same as the fluorinated alkyl group in the dialkyltin compound. 
     
     
         13 . The mixture according to  claim 12 , wherein the fluorinated monoalkyltin compound has formula (II) and the fluorinated dialkyltin compound has formula (III):
   (R f CH 2 )SnX 3   (II)
     (R f CH 2 ) 2 SnX 2   (III)
   
       wherein R f  is a fluorinated or partially fluorinated linear or branched alkyl group having about 2 to about 6 carbon atoms, and X is a hydrolytically or oxidatively unstable group. 
     
     
         14 . A method for forming a fluorinated oxostannate film comprising:
 vaporizing the mixture according to  claim 13 ;   providing a substrate;   physisorbing or chemisorbing the vaporized mixture onto the substrate; and   exposing the physisorbed or chemisorbed mixture to a sequence of hydrolysis and irradiation steps followed by an oxidation or second hydrolytic exposure to form the fluorinated oxostannate thin film on the substrate.