SILICON-CONTAINING UNDERLAYERS

Abstract

Wet-strippable underlayer compositions comprising one or more silicon-containing polymers comprising a backbone comprising SiO linkages, one or more organic blend polymers, and a cure catalyst are provided. These compositions are useful in the manufacture of various electronic devices.

Claims

1. A process comprising: (a) coating a substrate with a coating composition comprising one or more curable silicon-containing polymers comprising a backbone comprising SiO linkages, one or more organic blend polymers, and one or more organic solvents to form a curable silicon-containing polymer layer on the substrate; (b) curing the silicon-containing 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 by wet stripping.

2. The process of claim 1 wherein the organic blend polymer comprises as polymerized units one or more ethylenically unsaturated monomers.

3. The process of claim 2 wherein the organic blend polymer comprises as polymerized units one or more monomers of the formula ##STR00028## wherein Z is chosen from C.sub.6-30 aryl moiety, substituted C.sub.6-30 aryl moiety, CN, and C(O)R.sup.23; R.sup.20 is chosen from H, C.sub.1-10 alkyl, C.sub.1-10 haloalkyl, halo, C(O)R.sup.24; each of R.sub.21 and R.sup.22 are independently chosen from H, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, halo, and CN; each of R.sup.23 and R.sup.24 is independently chosen from OR.sup.25 and N(R.sup.26).sub.2; R.sup.25 is chosen from H, and C.sub.1-20 alkyl; and each R.sup.26 is independently chosen from H, C.sub.1-20 alkyl, and C.sub.6-20 aryl; wherein Z and R.sup.20 may be taken together to form a 5 to 7-membered unsaturated ring.

4. The process of claim 3 wherein the organic blend polymer comprises as polymerized units one or more monomers of the formula (1a) ##STR00029## wherein ADG is an acid decomposable group; and R.sup.1 is independently chosen from H, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, halo, and CN.

5. The process of claim 3 wherein the organic blend polymer comprises as polymerized units one or more monomers of the formula (1b) ##STR00030## wherein R.sup.5 is chosen from a C.sub.4-30 organic residue bound to the oxygen through a tertiary carbon or a C.sub.4-30 organic residue comprising an acetal functional group; and R is independently chosen from H, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, halo, and CN.

6. The process of claim 3 wherein the organic blend polymer comprises as polymerized units one or more monomers of the formula (2) ##STR00031## wherein R.sup.1 is independently chosen from H, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, halo, and CN; and R.sup.2 is a monovalent organic residue having a lactone moiety.

7. The process of claim 6 wherein the lactone moiety of R.sup.2 is a 5 to 7-membered ring or a substituted 5 to 7-membered ring.

8. The process of claim 1 wherein the coating composition further comprises one or more cure catalysts.

9. The process of claim 1 wherein the one or more silicon-containing polymers comprise as polymerized units one or more monomers chosen from formulae (3), (4), (5a), and (5b)
R.sup.3SiY.sub.3 (3)
SiY.sup.1.sub.4 (4)
R.sup.5.sub.2SiY.sup.2.sub.2 (5a)
R.sup.5.sub.3SiY.sup.2 (5b) wherein each Y, Y.sup.1 and Y.sup.2 is independently a hydrolyzable moiety chosen from halo, C.sub.1-10 alkoxy, and OC(O)R.sup.4; R.sup.3 is C.sub.1-30 hydrocarbyl moiety or substituted C.sub.1-30 hydrocarbyl moiety; each R.sup.4 is chosen from H, OH, C.sub.1-10 alkyl, and C.sub.1-10 alkoxy; and each R.sup.5 is independently C.sub.1-30 hydrocarbyl moiety or substituted C.sub.1-30 hydrocarbyl moiety.

10. The process of claim 9 wherein the one or more silicon-containing polymers comprise as polymerized units one or more units of formula (6) and optionally one or more units of formula (7) ##STR00032## wherein each R.sup.7 is independently chosen from C.sub.1-30 hydrocarbyl moiety, substituted C.sub.1-30 hydrocarbyl moiety, and OR.sup.8; each R.sup.8 is chosen from H, Si(R.sup.9).sub.xO(R.sup.10).sub.y, C.sub.1-30 hydrocarbyl moiety, and substituted C.sub.1-30 hydrocarbyl moiety; each R.sup.9 is independently C.sub.1-30 hydrocarbyl moiety or substituted C.sub.1-30 hydrocarbyl moiety; each R.sup.10 is independently H, C.sub.1-10 alkyl or C(O)C.sub.1-10 alkyl; each R.sup.11 is independently chosen from H, C.sub.1-10 alkyl, and C(O)C.sub.1-10 alkyl; n refers to the number of repeat units of formula (6) in the polymer and is an integer from 1 to 100; m refers to the number of repeat units of formula (7) in the polymer and is an integer from 0 to 50; x=0 to 3; Y=0 to 3, and x+y=3.

11. The process of claim 1 further comprising coating a layer of a high carbon-content organic coating on the substrate prior to step (a).

12. The process of claim 1 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.

13. A composition comprising: one or more curable silicon-containing polymers comprising a backbone comprising SiO linkages; one or more organic blend polymers comprising as polymerized units one or more monomers of formula (1b) ##STR00033## wherein R.sup.5 is chosen from a C.sub.4-30 organic residue bound to the oxygen through a tertiary carbon or a C.sub.4-30 organic residue comprising an acetal functional group; and R.sup.1 is independently chosen from H, C.sub.1-4 alkyl, C.sub.1-4haloalkyl, halo, and CN; and one or more cure catalysts.

14. The composition of claim 13 further comprising one or more organic solvents.

15. The composition of claim 13 wherein the organic blend polymer further comprises as polymerized units one or more monomers of formula (2) ##STR00034## wherein R.sup.1 is independently chosen from H, C.sub.1-4 alkyl, C.sub.1-4 haloalkyl, halo, and CN; and R.sup.2 is a monovalent organic residue having a lactone moiety.

16. The composition of claim 15 wherein the one or more monomers of formula (1b) and the one or more monomers of formula (2) are in a mole ratio of 1:99 to 99:1.

17. The composition of claim 15 wherein the blend polymer further comprises as polymerized units one or more ethylenically unsaturated third monomers.

18. The composition of claim 15 wherein the lactone moiety of R.sup.2 is a 5 to 7-membered ring or a substituted 5 to 7-membered ring.

19. The composition of claim 13 wherein the one or more silicon-containing polymers comprise as polymerized units one or more monomers chosen from formulae (3), (4), (5a), and (5b)
R.sup.3SiY.sub.3 (3)
SiY.sup.1.sub.4 (4)
R.sup.5.sub.2SiY.sup.2.sub.2 (5a)
R.sup.5.sub.3SiY.sup.2 (5b) wherein each Y, Y.sup.1 and Y.sup.2 is independently a hydrolyzable moiety chosen from halo, C.sub.1-10 alkoxy, and OC(O)R.sup.4; R.sup.3 is C.sub.1-30 hydrocarbyl moiety or substituted C.sub.1-30 hydrocarbyl moiety; each R.sup.4 is chosen from H, OH, C.sub.1-10 alkyl, and C.sub.1-10 alkoxy; and each R.sup.5 is independently C.sub.1-30 hydrocarbyl moiety or substituted C.sub.1-30 hydrocarbyl moiety.

20. The composition of claim 19 wherein the one or more silicon-containing polymers comprise as polymerized units one or more units of formula (6) and optionally one or more units of formula (7) ##STR00035## wherein each R.sup.6 is independently chosen from C.sub.1-30 hydrocarbyl moiety or substituted C.sub.1-30 hydrocarbyl moiety; each R.sup.7 is independently chosen from C.sub.1-30 hydrocarbyl moiety, substituted C.sub.1-30 hydrocarbyl moiety, and OR.sup.8; each R.sup.8 is chosen from H, Si(R.sup.9).sub.xO(R.sup.10).sub.y, C.sub.1-30 hydrocarbyl moiety, and substituted C.sub.1-30 hydrocarbyl moiety; each R.sup.9 is independently C.sub.1-30 hydrocarbyl moiety or substituted C.sub.1-30 hydrocarbyl moiety; each R.sup.10 is independently H, C.sub.1-10 alkyl or C(O)C.sub.1-10 alkyl; each R.sup.11 is independently chosen from H, C.sub.1-10 alkyl, and C(O)C.sub.1-10 alkyl; n refers to the number of repeat units of formula (6) in the polymer and is an integer from 1 to 100; m refers to the number of repeat units of formula (7) in the polymer and is an integer from 0 to 50; x=0 to 3; Y=0 to 3, and x+y=3.

Description

SYNTHESIS EXAMPLE 1

Preparation of Silicon Polymer 1

[0041] Hydrochloric acid (6.15 g of 12.1N) in water (156 g) was added to a mixture of methyltrimethoxysilane (99.80 g), phenyltrimethoxysilane (50.41 g), vinyltrimethoxysilane (62.75 g) and tetraethyl orthosilicate (294 g) and 2-propanol (467 g) over 10 min. The reaction mixture was stirred at room temperature for 1 hr., heated to reflux for 24 hr. and then cooled to room temperature. The solution was diluted with PGEE (800 g) and low boiling reaction mixture components were removed under reduced pressure. The resulting solution was diluted with PGEE to afford a final 10 wt % solution of Silicon Polymer 1 (M.sub.w=9000 Da).

SYNTHESIS EXAMPLE 2

Preparation of Silicon Polymer 2

[0042] Acetic acid (35.5 g) in water (160 g) was added to a mixture of methyltrimethoxysilane (99.8 g), phenyltrimethoxysilane (50.4 g), vinyltrimethoxysilane (62.8 g) and tetraethyl orthosilicate (294 g) and PGMEA (467 g) over 10 min. The reaction mixture was stirred at room temperature for 1 hr., heated to 85 C. for 6 hr. and then cooled to room temperature. Low boiling reaction mixture components were removed under reduced pressure and the resulting solution was diluted with PGMEA to afford a final solution of Silicon Polymer 2 (ca. 10-12 wt %) (M.sub.w=4000 Da).

SYNTHESIS EXAMPLE 3

Preparation of Silicon Polymer 3

[0043] Hydrochloric acid (0.265 g of 12.1N) in water (29.4 g) was added to a mixture of vinyltrimethoxysilane (4.75 g), phenyltrimethoxysilane (12.7 g), bis(triethoxysilyl)ethylene (83.5 g) and 2-propanol (160 g) over 10 min. The reaction mixture was stirred at room temperature for 1 hr., heated to reflux for 18 hr. and then cooled to room temperature. The solution was diluted with PGEE (300 g) and low boiling reaction mixture components were removed under reduced pressure. The resulting solution of Silicon Polymer 3 was diluted with PGEE to afford a final concentration of 10 wt % (M.sub.w=28000 Da).

SYNTHESIS EXAMPLE 4

Preparation of Silicon Polymer 4

[0044] Hydrochloric acid (6.15 g of 12.1N) in water (225 g) was added to a mixture of 3-(3-(triethoxysilyl)propyl)dihydrofuran-2,5-dione (223 g), phenyltrimethoxysilane (50.41 g), vinyltrimethoxysilane (62.75 g) and tetraethyl orthosilicate (294 g) and 2-propanol (467 g) over 10 min. The reaction mixture was stirred at room temperature for 1 hr., heated to reflux for 24 hr. and then cooled to room temperature. The solution was diluted with PGEE (800 g) and low boiling reaction mixture components were removed under reduced pressure. The resulting solution was diluted with PGEE to afford a final 10 wt % solution of Silicon Polymer 4 (M.sub.w=3900 Da).

SYNTHESIS EXAMPLE 5

Preparation of Organic Polymer 1

[0045] A solution of 2-hydroxyethyl methacrylate (HEMA), (3.34 g) gamma butyrolactone methacrylate (GBLMA), (4.37 g) and tert-butylmethacrylate (tBMA), (7.30 g) dissolved in 1,3-dioxolane (11.5 g) and a solution of V-65 initiator (2.55 g) dissolved in 2:1 v/v tetrahydrofurane/acetonitrile (2.55 g) were both added dropwise over 2 hr. to a reaction vessel containing 3-dioxolane (26.7 g) at 75 C. under a nitrogen blanket. After addition, the reaction solution was held at 75 C. for an additional two hr., cooled to room temperature, diluted with 15 g THF and isolated by drop-wise addition into 500 mL of stirred di-isopropylether. The precipitated polymer was collected by vacuum filtration and vacuum oven dried for 24 hr. to afford Polymer 1 as a white solid (9.40 g, 63% yield). M.sub.w was determined to be 3800 Da.

SYNTHESIS EXAMPLES 6-21

[0046] Organic Polymers 2 to 17, reported in Table 2 below, were synthesized according to Synthesis Example 5 above using the monomers listed in Table 1 below. Polymers 2 to 17 were isolated in 50-99% yield and had a M.sub.w in the range of 3500-3800 Da.

TABLE-US-00001 TABLE 1 [00010] Monomer 1 [00011] Monomer 2 [00012] Monomer 3 [00013] Monomer 4 [00014] Monomer 5 [00015] Monomer 6 [00016] Monomer 7 [00017] Monomer 8 [00018] Monomer 9 [00019] Monomer 10 [00020] Monomer 11 [00021] Monomer 12 [00022] Monomer 13 [00023] Monomer 14 [00024] Monomer 15 [00025] Monomer 16 [00026] Monomer 17 [00027] Monomer 18

TABLE-US-00002 TABLE 2 Organic Monomer A Monomer B Monomer C Monomer D Monomer E Example Polymer (mol %) (mol %) (mol %) (mol %) (mol %) 6 2 Monomer 1 Monomer 4 (40) (60) 7 3 Monomer 1 Monomer 2 Monomer 3 (25) (25) (50) 8 4 Monomer 5 Monomer 6 Monomer 3 (25) (40) (35) 9 5 Monomer 8 Monomer 2 Monomer 3 (25) (40) (35) 10 6 Monomer 5 Monomer 3 (50) (50) 11 7 Monomer 2 Monomer 3 (50) (50) 12 8 Monomer 2 Monomer 9 (50) (50) 13 9 Monomer 5 Monomer 9 (50) (50) 14 10 Monomer 5 Monomer 2 Monomer 3 (25) (40) (35) 15 11 Monomer 7 Monomer 10 Monomer 2 Monomer 11 Monomer 13 (20) (25) (30) (20) (5) 16 12 Monomer 2 Monomer 3 Monomer 18 Monomer 15 (28.3) (28.3) (28.3) (15) 17 13 Monomer 12 Monomer 4 (50) (50) 18 14 Monomer 15 Monomer 16 (50) (50) 19 15 Monomer 14 (100) 20 16 Monomer 4 Monomer 1 Monomer 17 (20) (30) (30) 21 17 Monomer 4 Monomer 3 (50) (50)

[0047] Comparative Formulation 1. Comparative Formulation 1 was prepared by combining 2.38 g of Silicon Polymer 1 from Synthesis Example 1 (Silicon Polymer Solution A); 0.640 g of a 0.1 wt % solution of tetrabutylammonium chloride in PGEE in 5.66 g of PGEE (Catalyst 1); and 8.24 g of ethyl lactate.

FORMULATION EXAMPLES 1-19

[0048] Formulations 1-19 of the invention, described in Table 4 below, were prepared according to the general procedure of Comparative Formulation 1, except that the components in Table 3 were used. Comparative Formulations 2 and 3, identified in Table 4, were similarly prepared. In Table 4, the heading Organic Polymer/OPS refers to the Organic Polymer of the invention from Examples 5 to 21 used to form the particular Organic Polymer Solutions from Table 3.

TABLE-US-00003 TABLE 3 Component Description Silicon Polymer Solution B Silicon Polymer 2 (11.3 wt % in PGMEA) Silicon Polymer Solution C Silicon Polymer 2 (10.8 wt % in PGMEA) Silicon Polymer Solution D Silicon Polymer 3 (10 wt % in PGEE) Silicon Polymer Solution E Silicon Polymer 4 (10 wt % in PGEE) Organic Polymer Solution OPS1 20 wt % of any of Organic Polymers 1-17 in PGMEA Organic Polymer Solution OPS2 10 wt % of any of Organic Polymers 1-17 in PGMEA Organic Polymer Solution OPS3 5 wt % of any of Organic Polymers 1-17 in PGMEA Organic Polymer Solution OPS4 10 wt % of any of Organic Polymers 1-17 in EL Organic Polymer Solution OPS5 10 wt % of any of Organic Polymers 1-17 in HBM Organic Polymer Solution OPS6 10 wt % of any of Organic Polymers 1-17 in PGEE Catalyst 2 0.1 wt % of tetramethylammonium chloride in PGMEA Catalyst 3 0.1 wt % of tetramethylammonium chloride in EL

TABLE-US-00004 TABLE 4 Silicon Organic Formu- Polymer Polymer/ Cata- lation Solution (g) OPS (g) lyst (g) Solvent (g) 1 B (37.2) Polymer 2/ 2 (0.600) PGMEA (254)/ OPS1 (8.99) EL (54.8) 2 C (3.10) Polymer 3/ 2 (0.480) PGMEA (18)/ OPS3 (1.33) EL (3.95) 3 C (1.86) Polymer 4/ 3 (0.288) PGMEA (9)/ OPS3 (1.73) EL (4.1) 4 Polymer 5/ PGMEA (9)/ OPS3 (1.73) EL (4.1) 5 Polymer 6/ PGMEA (9)/ OPS3 (1.73) EL (4.1) 6 Polymer 7/ PGMEA (9)/ OPS3 (1.73) EL (4.1) 7 Polymer 8/ PGMEA (9)/ OPS3 (1.73) EL (4.1) 8 Polymer 17/ PGMEA (9)/ OPS3 (1.73) EL (4.1) 9 Polymer 10/ PGMEA (9.9)/ OPS2 (0.863) EL (4.1) 10 Polymer 7/ PGMEA (9.9)/ OPS2 (0.863) EL (4.1) 11 B (1.78) Polymer 12/ PGMEA (6.3)/ OPS 4 (0.863) EL (7.8) 12 B (1.28) Polymer 13/ PGMEA (11.7)/ OPS2 (1.44) EL (2.4) 13 B (2.48) Polymer 16/ 3 (0.400) PGMEA (16.3)/ OPS2 (1.44) EL (3.3) 14 B (1.78) Polymer 14/ 3 (0.288) PGMEA (11.7)/ OPS2 (1.44) EL (2.4) 15 Polymer 15/ PGMEA (11.7)/ OPS2 (1.44) EL (2.4) 16 A (1.73) Polymer 2/ 1 (0.777) PGEE (5.4)/ OPS5 (1.15) HBM (7.8) 17 D (1.66) Polymer 3/ 1 (0.640) PGEE (5.4)/ OPS5 (0.712) HBM (8.2) 18 A (1.44) Polymer 11/ 1 (0.777) PGEE (5)/ OPS5 (1.44) HBM (7.6) 19 E (1.73) Polymer 3/ PGEE (5.4)/ OPS1 (1.15) HBM (7.8) Compar- D (2.38) 1 (0.640) PGEE (5)/ ative 2 HBM (8.9) Compar- E (2.88) 1 (0.254) PGEE (4.3)/ ative 3 HBM (8.9)

[0049] Wet Strippability. Formulation samples tested were filtered through 0.2 m polytetrafluoroethylene syringe and were spin-coated on bare 200 mm silicon wafers at 1500 rpm and baked at 240 C. for 60 sec. using an ACT-8 Clean Track (Tokyo Electron Co.). Film thickness after baking of each coated film was measured with an OptiProbe instrument from Therma-wave Co. The coated sample was then evaluated for SC-1 wet strippability using a mixture of 30% NH.sub.4OH/30% H.sub.2O.sub.2/water in a w/w/w ratio of 1/1/5, 1/1/10, 1/5/40, or 1/1/40. The SC-1 mixture was heated to 70 C. for the 1/1/5, 1/5/40 and 1/1/40 stripping mixtures, and heated to 45 C. for the 1/1/10 w/w/w stripping solution. Coupons of each coated wafer were immersed into the stripping solution for 5 min. The coupons were removed from the SC-1 mixture and rinsed with deionized water. The film thickness loss for each sample was calculated as the difference in film thickness before and after contact with the SC-1 stripping mixture. A separate film prepared as described above is optionally tested for SC-1 strippability after etching. Etching was performed for 60 sec. using RIE790 from Plasma-Therm Co. with oxygen gas, 25 sscm flow, 180 W of power, and 6 mTorr of pressure.

[0050] The data for a stripping mixture of 30% NH.sub.4OH/30% H.sub.2O.sub.2/water in a 1/1/5 w/w/w ratio are reported in Table 5, in Table 6 for a 1/5/40 w/w/w ratio, in Table 7 for a 1/1/10 w/w/w ratio, and in Table 8 for a 1/1/40 w/w/w ration. Data labeled as No Etch were calculated as a percentage by taking the difference in film thickness between the coated wafer and the film thickness after exposure to the SC-1 stripping mixture. Data labeled as After Etch were calculated as a percentage by taking the difference in film thickness between the coated wafer after exposure to oxygen etch and the film thickness after the same wafer was exposed to the SC-1 stripping mixture.

[0051] In Tables 5 to 8, the stripping data for Comparative Formulation 1 were normalized to 1.00, and designated with . Inventive examples that outperformed Comparative Formulation 1 by <2 times are designated with .square-solid.; inventive examples that outperformed Comparative Formulation 1 by 2 to 10 times are designated with ; inventive examples that outperformed Comparative Formulation 1 by 10 to 30 times are designated with ; and inventive examples that outperformed Comparative Formulation 1 by over 30 times are designated with .

TABLE-US-00005 TABLE 5 SC-1 1/1/5 w/w/w Formulation No Etch After Etch Comparative Formulation 1 1

TABLE-US-00006 TABLE 6 SC-1 1/5/40 w/w/w Formulation No Etch Comparative Formulation 1 1 2 3 4 5 6 .square-solid. 7 8 9 10 .square-solid. 17

TABLE-US-00007 TABLE 7 SC-1 1/1/10 w/w/w Formulation No Etch Comparative Formulation 1 11 12 13 14 15

TABLE-US-00008 TABLE 8 SC-1 1/1/40 w/w/w Formulation No Etch After Etch Comparative Formulation 1 16 .square-solid. 18 19

[0052] The data in Tables 5-8 clearly show that the formulations of the invention improve the wet strippability of silicon-containing materials.