Compositions for anti pattern collapse treatment comprising gemini additives

Abstract

A method of reducing defects of a semiconductor substrate whereby the substrate is rinsed with an aqueous composition containing a gemini additive of the general formula I after the development of a photoresist or a photolithographic mask ##STR00001## wherein X is a divalent group, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are substituted or unsubstituted monovalent groups, n is an integer from 1 to 5, or 1 to 10000 depending on R.sup.3 and R.sup.4, z is an integer, which is chosen so that the overall surfactant is electrically uncharged, and Z is a counter-ion.

Claims

1. A method, comprising: providing a patterned photoresist layer on a semiconductor substrate, wherein the patterned photoresist layer has line-space dimensions of 50 nm or less, rinsing the patterned photoresist layer with an aqueous composition consisting essentially of at least one gemini additive of the formula I and water, wherein a pH of the aqueous composition is adjusted to a pH of about 6 to about 8 prior to the rinsing, ##STR00020## wherein X is a divalent group, for each repeating unit 1 to n independently selected from the group consisting of (a) a linear or branched C.sub.1 to C.sub.20 alkanediyl, which may optionally be substituted and which may optionally be interrupted by up to 5 heteroatoms selected from O, N, or both, (b) a C.sub.5 to C.sub.20 cycloalkanediyl, which may optionally be substituted and which may optionally be interrupted by up to 5 heteroatoms selected from O, N, or both, (c) a C.sub.6 to C.sub.20 organic group of formula X.sup.1-A-X.sup.2, wherein X.sup.1 and X.sup.2 are independently selected from a C.sub.1 to C.sub.7 linear or branched alkanediyl and A is selected from a C.sub.5 to C.sub.12 aromatic moiety or a C.sub.5 to C.sub.30 cycloalkanediyl, which may optionally be substituted and which C atoms may optionally be interrupted by up to 5 heteroatoms selected from O, N, or both, and (d) a polyoxyalkylene diradical of formula II: ##STR00021## wherein p is 0 or 1, r is an integer from 1 to 100, and R.sup.5 is H or a linear or branched C.sub.1 to C.sub.20 alkyl group; R.sup.1 and R.sup.2 are monovalent groups independently selected from the group consisting of H, linear or branched C.sub.1 to C.sub.20 alkyl, C.sub.5 to C.sub.20 cycloalkyl, C.sub.5 to C.sub.20 aryl, C.sub.6 to C.sub.20 alkylaryl, C.sub.6 to C.sub.20 arylalkyl, C.sub.1 to C.sub.20 hydroxyalkyl, and C.sub.2 to C.sub.4 oxyalkylene homo or copolymers, all of which may optionally be substituted; R.sup.3 and R.sup.4 are monovalent groups independently selected from the group consisting of a linear or branched C.sub.5 to C.sub.30 alkyl group, a C.sub.5 to C.sub.30 cycloalkyl, a C.sub.1 to C.sub.20 hydroxyalkyl, and a C.sub.2 to C.sub.4 oxyalkylene homo or copolymers, all of which may optionally be substituted, and wherein pair-wise R.sup.3R.sup.4 and adjacent R.sup.4R.sup.4 and R.sup.3 R.sup.3 may optionally together form a bivalent group X, and may also be a continuation Q of the molecule by branching, and, if n is equal to or greater than 2, R.sup.3, R.sup.4 or R.sup.3 and R.sup.4 may also be hydrogen atoms; or R.sup.3 and R.sup.4 independently are represented by the formula VI: ##STR00022## wherein X.sup.3 is selected from a chemical bond and a linear or branched C.sub.1 to C.sub.4 alkanediyl, R.sup.5 is selected from the group consisting of OH, H and a linear or branched C.sub.1-C.sub.5 alkyl, R.sup.6 is selected from the group consisting of H, a linear or branched C.sub.1 to C.sub.20 alkyl, a C.sub.1 to C.sub.20 cycloalkyl, a C.sub.1 to C.sub.20 aryl, C.sub.1 to C.sub.20 alkylaryl and C.sub.1 to C.sub.20 arylalkyl, R.sup.7 is selected from the group consisting of H and linear or branched C.sub.1 to C.sub.10 alkyl; n is an integer from 1 to 5, and provided that, if a Q is present, n includes all repeating units of branches Q; Q is ##STR00023## z is an integer, which is chosen so that the overall surfactant is electrically uncharged; Z is a counter-ion.

2. The method according to claim 1, wherein X is selected from an unsubstituted linear or branched C.sub.3-C.sub.12 alkanediyl.

3. The method according to claim 1, wherein X is selected from the group consisting of butane-1,6-diyl, hexane-1,6-diyl, and octane-1,8-diyl.

4. The method according to claim 1, wherein X is selected from formula X.sup.3OX.sup.4, where X.sup.3 and X.sup.4 are a linear or branched C.sub.1-C.sub.9 alkanediyl.

5. The method according claim 1, wherein X.sup.1 and X.sup.2 are independently selected from the group consisting of methanediyl, ethanediyl, propanediyl and butanediyl and A is benzene or anthracene.

6. The method according to claim 1, wherein R.sup.1 and R.sup.2 are independently selected from C.sub.1-C.sub.12 alkanediyl.

7. The method according to claim 1, wherein R.sup.1 is H and R.sup.2 is independently selected from H, linear or branched C.sub.1 to C.sub.20 alkyl, C.sub.5 to C.sub.20 cycloalkyl, C.sub.5 to C.sub.20 aryl, C.sub.6 to C.sub.20 alkylaryl, C.sub.6 to C.sub.20 arylalkyl, C.sub.1 to C.sub.20 hydroxyalkyl, and C.sub.2 to C.sub.4 oxyalkylene homo or copolymers, all of which may optionally be substituted.

8. The method according to claim 1, wherein R.sup.3 and R.sup.4 independently are represented by the formula VI: ##STR00024## wherein X.sup.3 is selected from a chemical bond and a linear or branched C.sub.1 to C.sub.4 alkanediyl, R.sup.5 is selected from the group consisting of OH, H and a linear or branched C.sub.1-C.sub.5 alkyl, R.sup.6 is selected from the group consisting of H, a linear or branched C.sub.1 to C.sub.20 alkyl, a C.sub.1 to C.sub.20 cycloalkyl, a C.sub.1 to C.sub.20 aryl, C.sub.1 to C.sub.20 alkylaryl and C.sub.1 to C.sub.20 arylalkyl, R.sup.7 is selected from the group consisting of H and linear or branched C.sub.1 to C.sub.10 alkyl.

9. The method according to claim 1, wherein R.sup.3 and R.sup.4 independently are represented by the formula V: ##STR00025## wherein u is an integer of from 0 to 100; R.sup.8 is, for each repeating unit u independently, selected from H and a linear or branched C.sub.1 to C.sub.2 alkyl group, and R.sup.10 is selected from the group consisting of hydroxy, carboxy or its salts, amine, amide, sulphonamide, sulphonate or its salts, sulphate or its salts, phosphonate or its salts and phosphate or its salts.

10. The method according to claim 1, wherein the semiconductor substrate comprises structures comprising apertures of 30 nm or below.

11. The method according to claim 1 for cleaning the semiconductor substrate.

12. The method according to claim 1, wherein the patterned photoresist layer on the semiconductor substrate has line-space dimensions of 32 nm or less and aspect ratios of greater than 2.

13. The method according to claim 1, wherein the composition comprises, based on a complete weight of the solution, 0.0005 to 1% by weight of the gemini additive.

14. The method according to claim 1, wherein the semiconductor substrate is manufactured by a photolithographic process comprising: (i) exposing a photoresist layer on the semiconductor substrate to actinic radiation through a mask with or without an immersion liquid; (ii) developing the exposed photoresist layer with a developer solution to obtain a developed patterned photoresist layer having line-space dimensions of 32 nm or less and an aspect ratio >2; (iii) applying a chemical rinse solution to the developed patterned photoresist layer; and (iv) spin drying the semiconductor substrate after the application of the chemical rinse solution; wherein at least one of the immersion liquid and the chemical rinse solution, is an aqueous solution comprising the gemini additive.

15. The method according to claim 1, for preventing pattern collapse, for reducing line edge roughness, for preventing and removing watermark defects and for reducing defects by removing particles.

16. A method, comprising: providing a substrate having a patterned photoresist layer having line-space dimensions of 50 nm or less and aspect ratios of at least 2; contacting the substrate at least once with an aqueous solution consisting essentially of at least one gemini additive of the formula I and water, wherein a pH of the aqueous composition is adjusted to a pH of about 6 to about 8 prior to the contacting: ##STR00026## wherein X is a divalent group, for each repeating unit 1 to n independently selected from the group consisting of: (a) a linear or branched C.sub.1 to C.sub.20 alkanediyl, which may optionally be substituted and which may optionally be interrupted by up to 5 heteroatoms selected from O, N, or both, (b) a C.sub.5 to C.sub.20 cycloalkanediyl, which may optionally be substituted and which may optionally be interrupted by up to 5 heteroatoms selected from O, N, or both, (c) a C.sub.6 to C.sub.20 organic group of formula X.sup.1-A-X.sup.2, wherein X.sup.1 and X.sup.2 are independently selected from a C.sub.1 to C.sub.7 linear or branched alkanediyl and A is selected from a C.sub.5 to C.sub.12 aromatic moiety or a C.sub.5 to C.sub.30 cycloalkanediyl, which may optionally be substituted and which C atoms may optionally be interrupted by up to 5 heteroatoms selected from O, N, or both, and (d) a polyoxyalkylene diradical of formula II: ##STR00027## wherein p is 0 or 1, r is an integer from 1 to 100, and R.sup.5 is H or a linear or branched C.sub.1 to C.sub.20 alkyl group; R.sup.1 and R.sup.2 are monovalent groups independently selected from the group consisting of H, linear or branched C.sub.1 to C.sub.20 alkyl, C.sub.5 to C.sub.20 cycloalkyl, C.sub.5 to C.sub.20 aryl, C.sub.6 to C.sub.20 alkylaryl, C.sub.6 to C.sub.20 arylalkyl, C.sub.1 to C.sub.20 hydroxyalkyl, and C.sub.2 to C.sub.4 oxyalkylene homo or copolymers, all of which may optionally be substituted; R.sup.3 and R.sup.4 are monovalent groups independently selected from the group consisting of a linear or branched C.sub.5 to C.sub.30 alkyl group, a C.sub.5 to C.sub.30 cycloalkyl, a C.sub.1 to C.sub.20 hydroxyalkyl, and a C.sub.2 to C.sub.4 oxyalkylene homo or copolymers, all of which may optionally be substituted, and wherein pair-wise R.sup.3R.sup.4 and adjacent R.sup.4R.sup.4 and R.sup.3 R.sup.3 may optionally together form a bivalent group X, and may also be a continuation Q of the molecule by branching, and, if n is equal to or greater than 2, R.sup.3, R.sup.4 or R.sup.3 and R.sup.4 may also be hydrogen atoms; or R.sup.3 and R.sup.4 independently are represented by the formula VI: ##STR00028## wherein X.sup.3 is selected from a chemical bond and a linear or branched C.sub.1 to C.sub.4 alkanediyl, R.sup.5 is selected from the group consisting of OH, H and a linear or branched C.sub.1-C.sub.5 alkyl, R.sup.6 is selected from the group consisting of H, a linear or branched C.sub.1 to C.sub.20 alkyl, a C.sub.1 to C.sub.20 cycloalkyl, a C.sub.1 to C.sub.20 aryl, C.sub.1 to C.sub.20 alkylaryl and C.sub.1 to C.sub.20 arylalkyl, R.sup.7 is selected from the group consisting of H and linear or branched C.sub.1 to C.sub.10 alkyl; n is an integer from 1 to 5, and provided that, if a Q is present, n includes all repeating units of branches Q; Q is ##STR00029## z is an integer, which is chosen so that the overall surfactant is electrically uncharged; Z is a counter-ion; and removing the aqueous solution from the contact with the substrate, wherein the substrate from which the aqueous solution has been removed from the contact with the substrate, is essentially free from a collapsed pattern.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) As FIG. 1 is of exemplary nature, the depicted spatial and dimensional relationships are not to be construed as an exact replica of the practical conditions.

(2) In the Figures the reference numbers have the following meaning: 1 substrate, 2 photoresist patterns or high aspect ratio stack (HARS), 3 gemini additive, 4 cleaning solution containing Gemini additive, and

(3) FIG. 1 illustrates how the photoresist structures or a high aspect ratio stacks 2 are drawn towards each other by the capillary forces of the evaporating cleaning solution 4, which capillary forces lead to pattern collapse.

(4) FIG. 2 shows the result of a rinse treatment of photoresist Line-Space structures by using gemini surfactant A1 according to example 1.

(5) FIG. 3 shows the result of a rinse treatment of photoresist Line-Space structures by using gemini surfactant A2 according to example 2.

(6) FIG. 4 shows the result of a photoresist development treatment by using utra pure water without any additive according to comparative example 3.

EXAMPLES

Example 1

(7) The manufacture of patterned photoresist layers having features with line-space structures and line-width of 40 nm and an aspect ratio of about 2.5 using surfactant (A1). The space between the photoresist lines was 80 nm.

(8) Silicon wafers were provided with 100 nm thick layers of an immersion photoresist. The photoresist layers were exposed to UV radiation of a wavelength of 193 through a mask using ultrapure water as the immersion liquid. Thereafter, the exposed photoresist layers were baked and developed with an aqueous developer solution containing tetramethylammonium hydroxide (TMAH). The baked and developed photoresist layers were subjected to a chemical rinse treatment using a chemical rinse solution containing 0.002% by weight of surfactant (A1).

(9) ##STR00018##

(10) The chemical rinse solution was applied on the wafer as a puddle. Thereafter, the silicon wafers were spun dry.

(11) FIG. 2 shows the respective height profile measured by AFM after the rinse treatment by using gemini surfactant A1. The dried patterned photoresist layers having patterns with line-space dimensions of 40 nm and an aspect ratio of about 2.5 did not show any pattern collapse.

Example 2

(12) Example 1 was repeated except that gemini surfactant A2 was used instead of gemini surfactant A1 in the chemical rinse solution.

(13) ##STR00019##

(14) FIG. 3 shows the respective height profile measured by AFM after the rinse treatment by using gemini surfactant A2. The dried patterned photoresist layers having photoresist line-width dimensions of 40 nm and an aspect ratio of about 2.5 did not show any pattern collapse.

Example 3

(15) Example 1 was repeated except that ultra pure water without any additive was used in the chemical rinse solution.

(16) FIG. 4 shows the result of a photoresist development treatment by using ultra pure water without any additive. The dried patterned photoresist layers having photoresist line-width dimensions of 40 nm and an aspect ratio of about 2.5 showed significantly increased pattern collapse compared to the rinse according to examples 1 and 2.