Plasma enhanced atomic layer deposition of silicon-containing films
A method comprising: providing a substrate in a processing station comprising a substrate support and a showerhead, the substrate comprising a gap to be filled; and depositing silicon-containing film in the gap by a plasma-enhanced atomic layer deposition (PEALD) process comprising multiple cycles of operations (a)-(d): (a) a dose operation comprising flowing a silicon-containing precursor into the processing station via the showerhead to allow the silicon-containing precursor to adsorb onto the substrate; (b) after (a), flowing a purge gas into the processing station; (c) after (b), exposing the substrate to plasma species to react with the adsorbed silicon-containing precursor; and (d) after (c), flowing a purge gas into the processing station, wherein the silicon-containing precursor continues to flow into the processing station during at least (b).
1 . A method comprising:
providing a substrate in a processing station comprising a substrate support and a showerhead, the substrate comprising a gap to be filled; and
depositing silicon-containing film in the gap by a plasma-enhanced atomic layer deposition (PEALD) process comprising multiple cycles of operations (a)-(d):
(a) a dose operation comprising flowing a silicon-containing precursor into the processing station via the showerhead to allow the silicon-containing precursor to adsorb onto the substrate;
(b) after (a), flowing a purge gas into the processing station;
(c) after (b), exposing the substrate to plasma species to react with the adsorbed silicon-containing precursor; and
(d) after (c), flowing a purge gas into the processing station,
wherein the silicon-containing precursor continues to flow into the processing station during at least (b).
2 . The method of claim 1 , wherein the silicon-containing precursor continues to flow into the processing station during at least part of (c).
3 . The method of claim 1 , wherein the silicon-containing precursor continues to flow into the processing station during (c) and at least part of (d).
4 . The method of claim 1 , wherein after (a), the silicon-containing precursor flow continues into flow into the processing station at a decreasing flow rate.
5 . The method of claim 1 , wherein (a) comprises flowing an inert gas and a vaporized silicon-containing precursor from a silicon-containing precursor source fluidically connected to a gas delivery line via an outlet valve, the gas delivery line fluidically connected to the showerhead, and at the end of (a), closing the outlet valve.
6 . The method of claim 5 , wherein silicon-containing precursor in the gas delivery line continues to flow into the processing station after the outlet valve is closed.
7 . The method of claim 1 , further comprising diverting silicon-containing precursor from the processing station during one or more of (c) and (d).
8 . The method of claim 1 , wherein the plasma in (c) is a dual frequency RF plasma generated using high frequency (HF) and low frequency (LF) RF power.
9 . The method of claim 8 , further comprising increasing an inert gas flow into the processing station during (c).
10 . The method of claim 8 , wherein the HF power is at least 4 kW and the LF power is between 500 W and 5 kW.
11 . The method of claim 8 , further comprising sputtering and re-depositing silicon-containing film in the gap during deposition of the silicon-containing film in the gap.
12 . The method of claim 1 , wherein the plasma species are generated from oxygen (O 2 ).
13 . The method of claim 1 , wherein the plasma species are generated from nitrous oxide (N 2 O).
14 . The method of claim 1 , wherein the plasma species are generated from nitrogen (N 2 ).
15 . The method of claim 1 , wherein (b) is between 50-500 milliseconds in duration.
16 . The method of claim 1 , wherein the gap to be filled is a gap between memory stacks of a 3D NAND structure.
17 . The method of claim 1 , wherein the gap has aspect ratio of at least 20:1.
18 . The method of claim 1 , further comprising exposing the deposited film to an inhibition plasma before at least one of the multiple cycles.
19 . A method comprising:
providing a substrate in a processing station comprising a substrate support and a showerhead;
depositing a silicon-containing film on the substrate by a plasma-enhanced atomic layer deposition (PEALD) process comprising multiple cycles of operations (a)-(d):
(a) a dose operation comprising flowing a silicon-containing precursor into the processing station via the showerhead to allow the silicon-containing precursor to adsorb onto the substrate;
(b) after (a), flowing a purge gas into the processing station;
(c) after (b), exposing the substrate to plasma species to react with the adsorbed silicon-containing precursor; and
(d) after (c), flowing a purge gas into the processing station,
wherein the plasma in (c) is a dual frequency RF plasma generated using high frequency (HF) and low frequency (LF) RF power.
20 . The method of claim 19 , wherein the silicon-containing film fills a gap on the substrate.
21 . The method of claim 19 , wherein the silicon-containing film is a protective film non-conformally deposited on a structure having two stacks separated by a gap such that the protective film is deposited at the top of the stacks extending only partially into gap.
22 . The method of claim 21 , further comprising: performing one or more cycles of:
exposing the substrate including the protective film to an inhibition plasma comprising halogen species to inhibit deposition on a portion of the gap; and after exposing the substrate to the inhibition, depositing dielectric material in the gap.
23 . The method of claim 22 , wherein the protective film is etched during exposure to the inhibition plasma.
24 . The method of claim 21 , wherein the silicon-containing precursor continues to flow into the processing station during at least (b).
25 . A method comprising:
providing a substrate in a processing station comprising a substrate support and a showerhead, the substrate comprising a gap to be filled; and
depositing silicon-containing film in the gap by a plasma-enhanced atomic layer deposition (PEALD) process comprising multiple cycles of operations (a)-(d):
(a) a dose operation comprising flowing a silicon-containing precursor into the processing station via the showerhead to allow the silicon-containing precursor to adsorb onto the substrate;
(b) after (a), flowing a purge gas into the processing station;
(c) after (b), exposing the substrate to plasma species generated from a reactant gas to react with the adsorbed silicon-containing precursor; and
(d) after (c), flowing a purge gas into the processing station, wherein the purge gas is a different gas than the reactant gas and
wherein the reactant gas and/or the plasma species continue to flow into the processing station during at least (a).