Deposition of organosilsesquioxane films

Abstract

There is provided an array of alkyl substituted silsesquioxane thin film precursors having a structure wherein alkyl groups are bonded to the silicon atoms of a silsesquioxane cage. The alkyl groups may be the same as, or different than the other alkyl groups. In a first aspect, the present invention provides a composition comprising a vaporized material having the formula [R—SiO 1.5 ] x [H—SiO 1.5 ] y , wherein x+y=n, n is an integer between 2 and 30, x is an integer between 1 and n and y is a whole number between 0 and n. R is a C 1 to C 100 alkyl group. Also provided are films made from these precursors and objects comprising these films.

What is claimed is:  
     
         1 . A composition comprising a material having the formula  
       [R—SiO 1.5 ] x [H—SiO 1.5 ] y ,  wherein: 
 R is a C 1  to C 100  alkyl group;  
 x+y=n;  
 n is an integer between 2 and 30;  
 x is an integer between 1 and n; and  
 y is a number between 0 and n.  
   
     
     
         2 . The composition according to  claim 1 , wherein said composition is in a vapor state.  
     
     
         3 . The composition according to  claim 1 , wherein n is a member selected from the group consisting of the integers from 6 to 16, inclusive.  
     
     
         4 . The composition according to  claim 3 , wherein n is a member selected from the group consisting of the integers from 8 to 12.  
     
     
         5 . The composition according to  claim 1 , wherein R is a C 1  to C 20  straight-or branched-chain alkyl group.  
     
     
         6 . The composition according to  claim 5 , wherein R is a C 1  to C 16  straight- or branched-chain alkyl group.  
     
     
         7 . The composition according to  claim 6 , wherein R is a C 1  to C 6  straight- or branched-chain alkyl group.  
     
     
         8 . The composition according to  claim 1 , wherein about 75% of said vaporized material has a molecular weight of less than about 3000 daltons.  
     
     
         9 . The composition according to  claim 8 , wherein about 75% of said vaporized material has a molecular weight of less than about 1800 daltons.  
     
     
         10 . The composition according to  claim 9 , wherein about 75% of said vaporized material has a molecular weight of less than about 1600 daltons.  
     
     
         11 . A method of forming a low k dielectric film, said method comprising: 
 (a) depositing onto a substrate, a material comprising a film precursor having the formula:    [R—SiO 1 5 ] x [H—SiO 1.5 ] y ,    wherein 
 x+y=n;  
 n is an integer between 2 and 30;  
 x is an integer between 1 and n;  
 y is a whole number between 0 and n;  
 R is a C 1  to C 100  alkyl group.  
   
     
     
         12 . The method according to  claim 11 , wherein said depositing comprises a method selected from vapor deposition, spin-on, dip coating, spraying, sputtering and combinations thereof.  
     
     
         13 . The method according to  claim 16 , wherein said vapor deposition comprises a member selected from chemical vapor deposition, physical vapor deposition and combinations thereof.  
     
     
         14 . The method according to  claim 12 , wherein said chemical vapor deposition comprises a member selected from atmospheric chemical vapor deposition, low pressure chemical vapor deposition, plasma enhanced chemical vapor deposition and combinations thereof.  
     
     
         15 . A method of forming a low k dielectric film, said method comprising: 
 (a) vaporizing a material to form a vaporized film precursor, said material comprising a film precursor having the formula    [R—SiO 1.5 ] x [H—SiO 1.5 ] y ,    wherein 
 x+y=n;  
 n is an integer between 2 and 30;  
 x is an integer between 1 and n;  
 y is a whole number between 0 and n;  
 R is a C 1  to C 100  alkyl group; and  
   (b) depositing onto a substrate said vaporized film precursor to form a deposited film precursor.    
     
     
         16 . The composition according to  claim 15 , wherein n is a member selected from the group consisting of the integers from 6 to 16, inclusive.  
     
     
         17 . The method according to  claim 16 , wherein n is a member selected from the group consisting of the integers from 8 to 12.  
     
     
         18 . The method according to  claim 15 , wherein R is C 1  to C 20  straight- or branched-chain alkyl group.  
     
     
         19 . The method according to  claim 18 , wherein R is a C 1  to C 16  straight- or branched-chain alkyl group.  
     
     
         20 . The method according to  claim 19 , wherein R is a C 1  to C 6  straight- or branched-chain alkyl group.  
     
     
         21 . The method according to  claim 15 , wherein about 75% of said vaporized material has a molecular weight of less than about 3000 daltons.  
     
     
         22 . The method according to  claim 21 , wherein about 75% of said vaporized material has a molecular weight of less than about 1800 daltons.  
     
     
         23 . The method according to  claim 22 , wherein about 75% of said vaporized material has a molecular weight of less than about 1600 daltons.  
     
     
         24 . The method according to  claim 15 , wherein said vaporizing is carried out at a temperature of from about 50° C. to about 300° C.  
     
     
         25 . The method according to  claim 15 , wherein said vaporizing is performed under vacuum.  
     
     
         26 . The method according to  claim 15 , further comprising; 
 (c) curing said deposited film precursor.    
     
     
         27 . The method according to  claim 26 , wherein said curing is by a member selected from the group of heat, ultraviolet light, electron beam and combinations thereof.  
     
     
         28 . The method according to  claim 27 , wherein said curing is accomplished by heating to a temperature of from about 150° C. to about 700° C.  
     
     
         29 . The method according to  claim 28 , wherein said temperature is from about 200° C. to about 500° C.  
     
     
         30 . A low k dielectric film comprising a material having the formula  
       [H a SiO b ] c [(R 1 ) a SiO b ] d [(R 2 ) a SiO b ] n ,  wherein 
 R 1  and R 2  are members independently selected from C 1  to C 100  alkyl groups;  
 a is less than or equal to 1;  
 b is greater than or equal to 1.5; and  
 c, d and n are members independently selected from the group consisting of the integers greater than 10.  
   
     
     
         31 . The method according to  claim 30 , wherein R 1  and R 2  are independently selected from C 1  to C 20  straight- or branched-chain alkyl group.  
     
     
         32 . The method according to  claim 35 , wherein R 1  and R 2  are independently selected from C 1  to C 16  straight- or branched-chain alkyl groups.  
     
     
         33 . The method according to  claim 36 , wherein R 1  and R 2  are independently selected from C 1  to C 6  straight- or branched-chain alkyl groups.  
     
     
         34 . The method according to  claim 37 , wherein R 1  and R 2  are both methyl groups.  
     
     
         35 . The film according to  claim 30 , wherein said film is a porous film.  
     
     
         36 . The film according to  claim 30 , wherein said film has a dielectric constant of from about 0.1 to about 3.  
     
     
         37 . The film according to  claim 36 , wherein said film has a dielectric constant of from about 0.5 to about 2.  
     
     
         38 . A method for preparing a porous low k dielectric film having a preselected degree of porosity, said film comprising a material having the formula  
       [H a SiO b ] c [(R 1 ) a SiO b ] d [(R 2 ) a SiO b ] n ,  wherein 
 R 1  and R 2  are members independently selected from C 1  to C 100  alkyl groups;  
 a is less than or equal to 1;  
 b is greater than or equal to 1.5; and  
 c, d and n are members independently selected from the group consisting of the integers greater than 10, said method comprising: 
 (a) depositing a film precursor to form a deposited film precursor, said film precursor comprising a material having the formula  
 [R—SiO 1.5 ] x [H—SiO 1.5 ] y ,  
  wherein 
 x+y=n;  
 n is an integer between 2 and 30;  
 x is an integer between 1 and n;  
 y is a whole number between 0 and n;  
 R is a C 1  to C 100  alkyl group; and  
 
 (b) curing said deposited film precursor to form a low k dielectric film with a preselected degree of porosity.  
 
   
     
     
         39 . The method according to  claim 38 , wherein said curing is carried out using a method selected from the group of heat, ultraviolet light and combinations thereof.  
     
     
         40 . The method according to  claim 39 , wherein said curing is carried out by heating to a temperature of from about 150° C. to about 700° C.  
     
     
         41 . The method according to  claim 40 , wherein said temperature is from about 200° C. to about 500° C.  
     
     
         42 . The film according to  claim 38 , wherein said low k dielectric film has a dielectric constant of from about 0.1 to about 3.  
     
     
         43 . The film according to  claim 42 , wherein said low k dielectric film has a dielectric constant of from about 0.5 to about 2.  
     
     
         44 . An object comprising a low k dielectric film, said film comprising a material having the formula:  
       [H a SiO b ] c [(R 1 ) a SiO b ] d [(R 2 ) a SiO b ] n ,  wherein 
 R 1  and R 2  are members independently selected from C 1  to C 100  alkyl groups;  
 a is less than or equal to 1;  
 b is greater than or equal to 1.5; and  
 c, d and n are members independently selected from the group consisting of the integers greater than 10.  
   
     
     
         45 . The object according to  claim 44 , wherein said object comprises a wafer.  
     
     
         46 . The wafer according to  claim 45 , wherein said wafer comprises a member selected from Si, SiON, SiN, SiO 2 , Cu, Ta, TaN and combinations thereof.  
     
     
         47 . The wafer according to  claim 45 , wherein said wafer is a member selected from Si wafers, SiO 2  wafers and combinations thereof.  
     
     
         48 . The wafer according to  claim 47 , wherein said wafer is metallized.  
     
     
         49 . The metallized wafer according to  claim 48 , metallized with a member selected from copper, titanium, titanium nitride and combinations thereof.