Wet-strippable silicon-containing antireflectant
Wet-strippable antireflective compositions comprising one or more silicon-containing polymers that are free of Q-monomers and hydridosilanes as polymerized units are provided. These compositions are useful in the manufacture of various electronic devices.
1. A siloxane polymer comprising as polymerized units one or more first monomers of formula (1) or dimers thereof and one or more second monomers of formula (2) or dimers thereof
R 2 SiX 2 (1)
RSiX 3 (2)
wherein each R is independently chosen from aryl, aralkyl, alkyl, alkenyl, aralkenyl, and R 1 ; R 1 is a C 2-30 organic radial comprising one or more —C(O)—O—C(O)— moieties; and each X is a hydrolyzable moiety; wherein at least one R is R 1 ; wherein at least one R is chosen from C 6-20 aryl, substituted C 6-20 aryl, and benzyl; and wherein ≥30% of the monomers comprising the polymer comprise one or more functional moieties chosen from hydroxy, mercapto, epoxy, glycidyloxy, cyano, alkyleneoxy, sulfolanyl, and —C(O)—O—C(O)—; and wherein the polymer is free of monomers of the formula HSiX 3 and SiX 4 as polymerized units.
2. The siloxane polymer of claim 1 comprising 2 or more different monomers of formula (1) or dimers thereof.
3. The siloxane polymer of claim 1 comprising 2 or more different monomers of formula (2) or dimers thereof.
4. The siloxane polymer of claim 1 wherein one or more R groups are substituted with one or more moieties are chosen from C 1-20 alkyl, C 1-20 alkoxy, C 1-20 hydroxyalkyl, C 2-30 alkoxyalkyl, hydroxy, mercapto, epoxy, glycidyloxy, cyano, alkyleneoxy, and sulfolanyl.
5. The siloxane polymer of claim 1 wherein R 1 is a 5-7 membered cyclic anhydride.
6. The siloxane polymer of claim 1 wherein R 1 is chosen from an organic radical of the formula:
where R 2 is a chemical bond or a C 1-20 organic radical, A represents a 5-7 membered cyclic anhydride, and * represents the point of attachment to silicon.
7. The siloxane polymer of claim 6 wherein R1 is chosen from dihydrofuran-2,5-dionyleth-2-yl, dihydrofuran-2,5-dionylprop-3-yl, dihydrofuran-2,5-dionylbut-4-yl, dihydrofuran-2,5-dionylbut-3-yl, dihydrofuran-2,5-dionylpent-5-yl, dihydrofuran-2,5-dionylpent-4-yl, dihydrofuran-2,5-dionyl-2,2-dimethylprop-3-yl, dihydrofuran-2,5-dionyl-2-methylprop-3-yl, dihydrofuran-2,5-dionylprop-2-yl, dihydrofuran-2,5-dionylhex-6-yl, dihydrofuran-2,5-dionylhex-4-yl, dihydrofuran-2,5-dionylhex-3-yl, isobenzofuran-1,3-dionyl-5-eth-2-yl, isobenzofuran-1,3-dionyl-5-prop-3-yl, isobenzofuran-1,3-dionyl-5-but-4-yl, benzo[de]isochromene-1,3-dionyl-6-propyl, 5-propylhexahydroisobenzofuran-1,3-dione, (3aS,4R,5S,7R,7aS)-5-(trimethoxysilyl)hexahydro-4,7-methanoisobenzofuran-1,3-dione, (3aS,4R,5S,7R,7aR)-5-(trimethoxysilyl)hexahydro-4,7-epoxyisobenzofuran-1,3-dione, dihydro-2H-pyran-2,6(3H)-dionyl-4-methyl, dihydro-2H-pyran-2,6(3H)-dionyl-4-eth-2-yl, dihydro-2H-pyran-2,6(3H)-dionyl-4-prop-3-yl, dihydro-2H-pyran-2,6(3H)-diony-4-1hex-6-yl, tetrahydro-1H-cyclopenta[c]furan-1,3(3aH)-dionyl-3a-prop-3-yl, and hexahydroisobenzofuran-1,3-dionyl-3a-eth-2-yl.
8. The siloxane polymer of claim 1 wherein at least one R is chosen from phenyl, naphthyl, anthracenyl, tolyl, xylyl, mesityl, hydroxyphenyl, hydroxynaphthyl, and hydroxyanthracenyl.
9. The siloxane polymer of claim 1 , wherein the siloxane polymer comprises ≤45 wt % silicon.
10. A composition comprising the siloxane polymer of claim 1 and an organic solvent.
11. A method of patterning comprising: (a) coating a substrate with the composition of claim 10 to form a siloxane polymer layer on the substrate; (b) curing the siloxane polymer layer to form a siloxane underlayer; (c) disposing a layer of a photoresist on the siloxane underlayer; (d) pattern-wise exposing the photoresist layer to form a latent image; (e) developing the latent image to form a patterned photoresist layer having a relief image therein; (f) transferring the relief image to the substrate; and (g) removing the siloxane underlayer.
12. The method of claim 11 further comprising coating a layer of a high carbon-content organic coating on the substrate prior to step (a).
13. The method of claim 11 wherein the siloxane underlayer is removed by a wet stripping step.
14. The method of claim 13 wherein the wet stripping step comprises contacting the siloxane underlayer with a mixture of sulfuric acid and hydrogen peroxide or a mixture of ammonia and hydrogen peroxide.