Precursors for silicon dioxide gap fill
A full fill trench structure is described, including a microelectronic device substrate having a high aspect ratio trench therein and filled with silicon dioxide of a substantially void-free character and substantially uniform density throughout its bulk mass. A method of manufacturing a semiconductor product also is described, involving use of specific silicon precursor compositions for forming substantially void-free and substantially uniform density silicon dioxide material in the trench. The precursor fill composition may include silicon and germanium, to produce a microelectronic device structure including a GeO 2 /SiO 2 trench fill material. A suppressor component may be employed in the precursor fill composition, to eliminate or minimize seam formation in the cured trench fill material.
1. A full fill trench structure comprising a microelectronic device substrate having a high aspect ratio trench therein and a full filled mass of silicon dioxide in said trench, said silicon dioxide being of a substantially void-free character and having a substantially uniform density throughout its bulk mass, as formed by full fill of the trench with a silicon dioxide precursor composition, and hydrolysis and condensation chemical reactions of the precursor composition to form the silicon dioxide full filled mass in the trench.
2. The full fill trench structure of claim 1 , wherein said precursor composition comprises a precursor silicon compound selected from the group consisting of:
(i) aminosilanes of the formula (R 1 R 2 N) 4-x SiR x , wherein x is an integer having a value in a range of from 0 to 3, and each R, R 1 , and R 2 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(ii) alkoxysilanes of the formula (RO) 4-x SiR 1 x , wherein x is an integer having a value in a range of from 0 to 3, and each R and R 1 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(iii) alkoxydisilanes of the formula (RO) 3-x R 1 x Si—Si(OR) 3-x R 1 x , wherein x is an integer having a value in a range of from 0 to 2, and each R and R 1 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(iv) aminodisilanes of the formula (R 1 R 2 N) 3-x R x Si—Si(NR 1 R 2 ) 3-x R x , wherein x is an integer having a value in a range of from 0 to 2, and each R, R 1 , and R 2 is independently selected from among hydrogen, branched or unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(v) aminodisiloxanes of the formula (R 1 R 2 N) 3-x R x Si—O—Si(NR 1 R 2 ) 3-x R x , wherein x is an integer having a value in a range of from 0 to 2, and each R, R 1 , and R 2 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(vi) alkoxydisiloxanes of the formula (RO) 3-x R 1 x Si—O—Si(OR) 3-x R 1 x , wherein x is an integer having a value in a range of from 0 to 2, and each R and R 1 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(vii) aminodisilazanes of the formula (R 1 R 2 N) 3-x R x Si—NH—Si(NR 1 R 2 ) 3-x R x , wherein x is an integer having a value in a range of from 0 to 2, and each R, R 1 , and R 2 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(viii) alkoxydisilazanes of the formula (RO) 3-x R 1 x Si—NH—Si(OR) 3-x R 1 x , wherein x is an integer having a value in a range of from 0 to 2, and each R and R 1 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(ix) chloroaminosilanes of the formulae Cl 4-x Si(NR 1 R 2 ) x , wherein x is an integer having a value in a range of from 0 to 3, (R 1 R 2 N) 3-x Cl x Si—Si(NR 1 R 2 ) 3-x Cl x , wherein x is an integer having a value of 1 or 2, (R 1 R 2 N) 3-x Cl x Si—O—Si(NR 1 R 2 ) 3-x Cl x , wherein x is an integer having a value of 1 or 2, and (R 1 R 2 N) 3-x Cl x Si—NH—Si(NR 1 R 2 ) 3-x Cl x , wherein x is an integer having a value of from 1 or 2, and each R 1 and R 2 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(x) cyclosiloxanes and cyclosilazanes of the formulae:
wherein n is an integer having a value in the range of from 0 to 4, and each R 1 and R 2 is selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, C 6 -C 13 aryl, C 1 -C 6 dialkylamino, and C 1 -C 6 alkoxide;
(xi) linear polysiloxanes and polysilazanes;
(xii) silicon compounds of general formulae R 4-x SiL x wherein x is an integer having a value of from 1 to 3, and L 3-x R x Si-SiL 3-x R x wherein x is an integer having a value of from 0 to 2, L is selected from isocyanato (NCO), methylethylketoxime (R 1 R 2 C═N—O—), trifluoroacetate (CF 3 OCO), triflate (CF 3 SO 3 ), acyloxy (ROCO), β-diketonate (R 1 COCHCOR 2 ), β-diketiminate (R 1 CNR 2 CHCOR 3 ), β-diiminate (R 1 CNR 2 CHCNR 2 R 3 ), amidinate (RC(NR 1 ) 2 ), guanidinate {(R 1 R 2 N)C(NR 3 ) 2 }, alkylamino (NR 1 R 2 ), hydride, alkoxide (RO), and formato (HCOO) and each R, R 1 , R 2 , and R 3 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(xiii) oxiranylsilanes of the formulae
wherein x is an integer having a value in a range of from 0 to 3, n is an integer having a value in a range of 0 to 3, and each R 1 , R 2 , and R 3 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, C 6 -C 13 aryl, C 1 -C 6 alkylamino, and C 1 -C 6 alkoxide;
(xiv) silicon precursors containing ethylacetate groups, of the formula (ROCOCH 2 CH 2 ) x Si(OR 1 ) 4-x , wherein x is an integer having a value in a range of from 1 to 4, and each of R and R 1 is independently selected from among hydrogen, branched and unbranched C 1 -C 6 alkyl, C 3 -C 8 cycloalkyl, and C 6 -C 13 aryl;
(xv) (tBuHN) 2 (H 2 N)Si—Si(NH 2 )(NHtBu) 2 wherein tBu is tertiary butyl; and
(xvi) pre-polymer partial hydrolysis products of the foregoing compounds (i)-(xv).
3. The full fill trench structure of claim 2 , wherein said precursor silicon compound is hydrolyzed to a sol comprising Si(OH) 4 and said sol is condensed by condensation reaction in the presence of a condensing agent selected from the group consisting of ammonia, amines, disilanes, silicon tetrachloride, and chlorine-substituted compounds.
4. The full fill trench structure of claim 2 , wherein said precursor silicon compound is hydrolyzed in exposure to at least one agent selected from the group consisting of moisture, water and protic solvents.
5. The full fill trench structure of claim 2 , wherein said precursor silicon compound comprises aminosilane of the formula H 4-x Si(NR 2 ) x wherein x has the same integer value of from 1 to 3, and a chloroaminosilane is added to said aminosilane in a catalytically effective amount to catalyze condensation reaction of said aminosilane.
6. The full fill trench structure of claim 5 , wherein said chloroaminosilane comprises Cl 4-x Si(NR 2 ) x , wherein x is an integer having a value in a range of from 1 to 3.
7. The full fill trench structure of claim 6 , wherein said chloroaminosilane is added in an amount of from 0.05-5% weight percent, based on total weight of said chloroaminosilane and said aminosilane.
8. The full fill trench structure of claim 2 , wherein said precursor silicon compound comprises an alkoxysilane, and a chloro-substituted silane or chloro-substituted disilane is added to said alkoxysilane in a catalytically effective amount to catalyze condensation reaction of said alkoxysilane.
9. The full fill trench structure of claim 8 , wherein said chloro-substituted silane or chloro-substituted disilane is added in an amount of from 0.05-5% weight percent, based on total weight of said alkoxysilane and said chloro-substituted silane or chloro-substituted disilane.
10. The full fill trench structure of claim 2 , wherein said precursor silicon compound comprises hexaethylaminodisilane.
11. The full fill trench structure of claim 2 , wherein said precursor silicon compound comprises (tBuHN) 2 (H 2 N)Si—Si(NH 2 )(NHtBu) 2 .
12. The full fill trench structure of claim 2 , wherein said precursor silicon compound comprises Si(NMe 2 ) 4 .
13. The full fill trench structure of claim 1 , wherein said silicon dioxide has been further processed for densification thereof after the hydrolysis and condensation chemical reactions.
14. The full fill trench structure of claim 13 , wherein said densification is effected by exposure of the silicon dioxide to at least one of oxygen exposure, ultraviolet radiation, and low-temperature heating.
15. The full fill trench structure of claim 1 , wherein the silicon dioxide precursor composition includes a composition selected from the group consisting of:
(a) precursor compositions of the formula (RO) 4-x SiH x , wherein x is an integer having a value of from 0 to 3;
(b) precursor compositions of the formula H 4-x Si(NR 2 ) x , wherein x is an integer having a value of from 1 to 4;
(c) precursor compositions of the formula H 4-x Si(NHR) x , wherein x is an integer having a value of from 1 to 4;
(d) precursor compositions of the formula (RO) 3-x H x Si—Si(OR) 3-x H x , wherein x is an integer having a value of from 0 to 2;
(e) precursor compositions of the formula (NR 1 R 2 ) 3-x H x Si—Si(NR 1 R 2 ) 3-x H x wherein x is an integer having a value in a range of from 0 to 2, and
each R, R 1 , R 2 is independently selected from among hydrogen, and branched and unbranched C 1 -C 6 alkyl.
16. The full fill trench structure of claim 1 , wherein the silicon dioxide precursor composition includes a composition selected from the group consisting of silicon precursors in which the silicon atom is coordinated with ligands including at least one of isocyanato, methylethylketoxime, trifluoroacetate, triflate (F 3 SO 3 H), alkylamines, hydrides, alkoxides, disilanes, and formato.