Methods for filling a gap and related systems and devices
Methods and related systems for filling a gap feature comprised in a substrate are disclosed. The methods comprise a step of providing a substrate comprising one or more gap features into a reaction chamber. The one or more gap features comprise an upper part comprising an upper surface and a lower part comprising a lower surface. The methods further comprise a step of subjecting the substrate to a plasma treatment. Thus, the upper surface is inhibited while leaving the lower surface substantially unaffected. Then, the methods comprise a step of selectively depositing a silicon-containing material on the lower surface.
1. A method for filling a gap feature on a substrate surface, the method comprising, in the given order:
a step of positioning a substrate on a substrate support in a reaction chamber, the substrate comprising one or more gap features, the one or more gap features comprising an upper part comprising an upper surface and a lower part comprising a lower surface;
a step of subjecting the substrate to a plasma pre-treatment, thereby inhibiting the upper surface while leaving the lower surface substantially unaffected; and,
a step of selectively depositing a silicon-containing material on the lower surface;
wherein the step of selectively depositing a silicon-containing material on the lower surface comprises a cyclical process, the cyclical process comprising a plurality of sub cycles, a sub cycle comprising, in the given order:
a step of exposing the substrate to a silicon precursor in a silicon precursor pulse, thereby forming chemisorbed silicon precursor on the lower surface; and,
a step of exposing the substrate to a post silicon precursor pulse plasma treatment, thereby allowing one or more reactive species comprised in the plasma to react with the chemisorbed silicon precursor on the lower surface;
wherein the silicon precursor comprises an amine group and two or more silicon atoms.
2. The method according to claim 1 wherein the amine group is selected from NH 2 , NHR i , and NR i R ii , with at least one of R i and R ii being a C 1 to C 4 alkyl.
3. The method according to claim 1 wherein the silicon precursor comprises a compound selected from the list consisting of an aminosilane, a silylamine, and a cyclosiloxane.
4. The method according to claim 1 wherein the silicon precursor comprises an alkylaminosilane.
5. The method according to claim 1 wherein the silicon precursor comprises a compound selected from SiR 1 R 3 R 4 —SiR 2 R 5 R 6 , SiR 1 R 3 R 4 —SiR 5 R 6 —SiR 2 R 7 R 8 , and SiR 1 R 3 R 4 —SiR 2 R 5 —SiR 6 R 7 R 8 , wherein R 1 and R 2 are NR 9 R 10 , with R 3 , R 4 , R 5 , R 6 R 7 , R 8 R 9 , and R 10 being independently selected from H and a C 1 to C 4 alkyl6.
6. The method according to claim 1 wherein the silicon precursor comprises a silylamine.
7. The method according to claim 6 wherein the silicon precursor comprises a compound that can be represented by a chemical structure according to formula (1)
wherein R 11 and R 12 are independently selected from H and a C 1 to C 4 alkyl.
8. The method according to claim 1 wherein the silicon precursor comprises a cyclosiloxane comprising at least one amine group.
9. The method according to claim 1 wherein the plasma pre-treatment comprises subjecting the substrate to a noble gas plasma.
10. The method according to claim 1 wherein the plasma pre-treatment comprises subjecting the substrate to a nitrogen-containing plasma.
11. The method according to claim 1 wherein the plasma pre-treatment comprises subjecting the substrate to a nitrogen and hydrogen-containing plasma.
12. The method according to claim 1 wherein the plasma pre-treatment comprises subjecting the substrate to a first plasma treatment and subjecting the substrate to a second plasma treatment.
13. The method according to claim 12 wherein the first plasma treatment comprises generating a nitrogen-containing plasma in the reaction chamber.
14. The method according to claim 13 wherein the nitrogen-containing plasma is a N 2 -containing plasma.
15. The method according to claim 12 wherein the second plasma treatment comprises generating a noble gas-containing plasma in the reaction chamber.
16. The method according to claim 1 comprising executing a plurality of super cycles, a super cycle comprising
the step of subjecting the substrate to a plasma pre-treatment; and,
the step of selectively depositing a silicon-containing material on the lower surface.
17. The method according to claim 1 wherein the post silicon precursor pulse plasma treatment comprises generating an oxygen-containing plasma in the reaction chamber, and wherein the silicon-containing material comprises silicon oxide.
18. The method according to claim 1 wherein, during the step of subjecting the substrate to a plasma pre-treatment, the silicon precursor is diverted through a silicon precursor bypass duct.
19. The method according claim 1 wherein, during the step of exposing the substrate to a silicon precursor, a plasma gas is diverted through a plasma gas bypass duct.
20. A semiconductor processing apparatus comprising:
a reaction chamber comprising a substrate support for supporting a substrate comprising one or more gap features;
a heater constructed and arranged to heat the substrate in the reaction chamber;
a first plasma gas source in fluid communication with the reaction chamber via a first plasma gas valve;
a second plasma gas source in fluid connection with the reaction chamber via a second plasma gas valve;
a third plasma gas source in fluid connection with the reaction chamber via a third plasma gas valve;
a plasma module comprising a radio frequency power source constructed and arranged to generate a plasma in the reaction chamber;
one or more silicon precursor sources in fluid connection with the reaction chamber via one or more precursor valves; and,
a controller configured for causing the apparatus to perform a method according to claim 1 .