Methods of forming high aspect ratio openings and methods of forming high aspect ratio features
Methods of forming high aspect ratio openings. The method comprises removing a portion of a dielectric material at a temperature less than about 0° C. to form at least one opening in the dielectric material. The at least one opening comprises an aspect ratio of greater than about 30:1. A protective material is formed in the at least one opening and on sidewalls of the dielectric material at a temperature less than about 0° C. Methods of forming high aspect ratio features are also disclosed, as are semiconductor devices.
1. A method of forming high aspect ratio openings, comprising:
removing a portion of a dielectric material at a temperature less than about 0° C. to form at least one opening in the dielectric material, the at least one opening comprising an aspect ratio of greater than about 30:1; and
forming a protective material in the at least one opening and on sidewalls of the dielectric material using atomic layer deposition (ALD), molecular layer deposition (MUD), or plasma chemical vapor deposition (CVD) at a temperature between about −1.00° C. and about −20° C., the protective material comprising a boron-containing material, a sulfur-containing material, or a metal material.
2. The method of claim 1 , wherein forming a protective material in the at least one opening and on sidewalls of the dielectric material comprises forming the protective material comprising a sulfur-containing material.
3. The method of claim 1 , wherein forming a protective material in the at least one opening and on sidewalls of the dielectric material comprises forming the protective material at a temperature of from about −50° C. to about −60° C.
4. The method of claim 1 , wherein removing a portion of a dielectric material at a temperature less than about 0° C. to form at least one opening in the dielectric material comprises forming the at least one opening exhibiting an aspect ratio of greater than about 50:1.
5. The method of claim 4 , wherein removing a portion of a dielectric material comprises removing the portion of the dielectric material at a first pressure between about 1 mTorr and about 10 Torr and forming a protective material comprises forming the protective material at a second pressure between about 20 mTorr and about 1 Torr.
6. The method of claim 4 , wherein forming a protective material in the at least one opening and on sidewalls of the dielectric material comprises forming the protective material with a thickness of between about 1 nm and about 10 nm.
7. The method of claim 4 , wherein removing a portion of a dielectric material comprises removing the portion of the dielectric material with a plasma and forming a protective material comprises forming the protective material in the absence of a plasma.
8. A method of forming high aspect ratio features, comprising:
forming openings in a stack of dielectric materials at a temperature of less than about 0° C., the openings comprising a first depth;
forming a protective material at a temperature between about −100° C. and about −40° C. on sidewalk of the stack exposed to the first depth;
extending the openings to a second depth;
forming another protective material at a temperature between about −100° C. and about −40° C. on sidewalls of the stack exposed to the second depth;
extending the openings to a final depth comprising an aspect ratio of at least about 30:1;
forming an additional protective material at a temperature between about −100° C. and about −40° C. on sidewalls of the stack exposed to the final depth; and
forming features in the openings.
9. The method of claim 8 , wherein forming features in the openings comprises forming the feature in the openings are selected from a group consisting of capacitors, pillars and channel regions.
10. The method of claim 8 , wherein forming features in the openings comprises forming the features comprising capacitors.
11. The method of claim 8 , wherein forming openings in a stack of dielectric materials comprises forming the openings in the stack comprising 50 tiers of alternating dielectric materials.
12. The method of claim 8 , wherein forming openings in a stack of dielectric materials comprises forming the openings in the stack comprising 80 tiers of alternating dielectric materials.
13. The method of claim 8 , further comprising removing the protective material from the openings.
14. The method of claim 13 , wherein removing the protective material from the openings comprises removing the protective material by sublimation.
15. The method of claim 13 , wherein removing the protective material from the openings comprises removing the protective material from the openings by exposing the protective material to a temperature of at least 5° C.
16. The method of claim 7 , wherein extending the openings to a second depth and forming another protective material at a temperature between about −100° C. and about −40° C. on sidewall s of the stack comprises conducting the extending and the forming in a same reaction chamber.
17. A method of forming high aspect ratio openings, comprising:
substantially simultaneously introducing an etch gas, an additive gas, and a protective material precursor into a chamber comprising a semiconductor structure, the etch gas comprising:
at least one material selected from the group consisting of carbon tetrafluoride (CF 4 ), nitrogen trifluoride (NF 3 ), trifluoromethane (CHF 3 ), methyl fluoride (CH 3 F), difluoromethane (CH 2 F 2 ), octofluorocyclobutane (C 4 F 8 ), hexafluoro-1,3, butadiene (C 4 F 6 ), cesium octofluoride (CsF 8 ), trifluoroiodomethane (CF 3 I), trifluorobromomethane (CF 3 Br), borontrifluoride (BF 3 ), sulfur hexafluoride (SF 6 ), chlorine (Cl 2 ), hydrogen bromide (HBr, hydrogen tetrabromide, bromine trifluoride (BrF 3 ), bromine octofluoride (BrF 8 ), bromine heptafluoride (BrF 7 ), and krypton hexabromine (KrBr 6 ),
wherein substantially simultaneously introducing the etch gas, the additive gas, and the protective material precursor into the chamber comprises:
removing a portion of a dielectric material of the semiconductor structure at a temperature less than about −20° C. to form at least one opening in the dielectric material in a single act, the at least one opening comprising an aspect ratio of greater than about 30:1; and
substantially simultaneously forming a protective material in the at least one opening and on sidewalls of the dielectric material at a temperature less than about −20° C.
18. The method of claim 17 , further comprising removing the protective material from the at least one opening by heating the dielectric material to above 5° C.
19. The method of claim 17 , wherein substantially simultaneously introducing an etch gas, an additive gas, and a protective material precursor into a chamber comprising a semiconductor structure comprises introducing gases to generate a pressure in the chamber between about 20 mTorr and about 1 Torr.
20. The method of claim 17 , wherein substantially simultaneously introducing an etch gas, an additive gas, and a protective material into a chamber comprises introducing the additive gas selected from the group consisting of H 2 , O 2 , CO, CO 2 , COS, CH 4 , C x H y , H 2 S, NH 3 , Ne, Ar, Kr, and Xe and the protective material precursor selected from the group consisting of an insulative organic polymer, a conductive organic polymer, a boron-containing material, a sulfur-containing material, and a metal.