Plasma activated conformal dielectric film deposition

Patent metadata

Field	Value
Publication number	US-9611544-B2
Application number	US-201113224240-A
Country	US
Kind code	B2
Filing date	Sep 1, 2011
Priority date	Apr 15, 2010
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

Methods of depositing a film on a substrate surface include surface mediated reactions in which a film is grown over one or more cycles of reactant adsorption and reaction. In one aspect, the method is characterized by intermittent delivery of dopant species to the film between the cycles of adsorption and reaction.

First claim

What is claimed is:

1. A method of depositing a nitrogen and/or carbon doped dielectric film stack on a substrate surface in a reaction chamber, the method comprising:
depositing a first dielectric portion of the dielectric film stack by a process comprising two or more cycles of dielectric deposition, each cycle comprising:
(a) introducing a dielectric film precursor into the reaction chamber under conditions allowing the precursor to adsorb onto the substrate surface;
(b) thereafter purging at least some unadsorbed precursor from the reaction chamber while some precursor remains adsorbed on the substrate surface;
(c) exposing the substrate surface to plasma to drive a reaction of the dielectric film precursor adsorbed on the substrate surface to form a portion of the dielectric film stack;

forming a first nitrogen and/or carbon rich portion of the dielectric film stack after depositing the first dielectric portion, by a process comprising:
(d) introducing a carbon and/or nitrogen-containing dopant species, not introduced during (a)-(c), into the reaction chamber under conditions allowing the dopant species to contribute nitrogen and/or carbon to the partially-formed dielectric film stack;

depositing a second dielectric portion of the dielectric film stack after forming the first nitrogen and/or carbon rich portion, by a process comprising two or more cycles of dielectric deposition, each cycle comprising (a)-(c); and
forming a second nitrogen and/or carbon rich portion of the dielectric film stack after depositing the second dielectric portion, by a process comprising (d);

wherein after deposition of the dielectric film stack, the nitrogen and/or carbon concentration in any of the first or second nitrogen and/or carbon rich portions of the stack is greater than the nitrogen and/or carbon concentration in any of the first or second dielectric portions of the stack and wherein nitrogen and/or carbon is present in each of the first and second dielectric portions of the stack.

2. The method of claim 1 , further comprising flowing an oxidant into the reaction chamber prior to and during the two or more cycles of dielectric deposition comprising (a)-(c) for depositing the first and second dielectric portions of the dielectric film stack.

3. The method of claim 2 , wherein during (a) the dielectric film precursor and the oxidant co-exist in vapor phase in the reaction chamber and wherein during (a) and (b) the precursor and the oxidant do not appreciably react with one another in the reaction chamber until exposure to plasma in (c).

4. The method of claim 2 , wherein the oxidant is nitrous oxide.

5. The method of claim 1 , wherein the processes for forming the first and second nitrogen and/or carbon rich portions of the dielectric film stack further comprise:
(e) reacting the carbon and/or nitrogen-containing dopant species to contribute nitrogen and/or carbon to the partially-formed dielectric film stack.

6. The method of claim 5 , wherein (e) further comprises exposing the carbon and/or nitrogen-containing dopant species to a plasma.

7. The method of claim 1 , further comprising exposing the substrate surface to the carbon and/or nitrogen-containing dopant species prior to performing (a) to deposit the first dielectric portion of the dielectric film stack.

8. The method of claim 1 , wherein the processes for depositing the first and second dielectric portions of the dielectric film stack each comprise three or more cycles of dielectric film deposition, each cycle comprising (a)-(c).

9. The method of claim 1 , wherein the dielectric film precursor is selected from the group consisting of dichlorosilane, BTBAS and BDEAS.

10. The method of claim 1 , wherein the carbon and/or nitrogen-containing dopant species is selected from the group consisting of hydrocarbons, alcohols, ketones, aldehydes, ethers, esters, carboxylic acids, oxolanes, and furans.

11. The method of claim 10 , wherein the carbon and/or nitrogen-containing dopant species is selected from the group consisting of methane, ethane, propane, acetylene, ethylene, propylene, t-amyl alcohol, ethanol, propanol, ethyleneglycol, and propyne.

12. The method of claim 1 , wherein the carbon and/or nitrogen-containing dopant species is selected from the group consisting of ammonia, amines, nitriles, amides, nitrogen-containing heterocyclic compounds, and amino alcohols.

13. The method of claim 12 , wherein the carbon and/or nitrogen-containing dopant species is selected from the group consisting of ammonia, hydrazine, elemental nitrogen, acetonitrile, t-butylamine, ethanolamine, ethylamine, and triethylamine.

14. The method of claim 1 , wherein the amount of film deposited during one cycle of dielectric deposition (a)-(c) is between about 0.5 to 5 Angstroms.

15. The method of claim 1 , wherein the total film thickness is between about 10-20000 Angstroms.

16. The method of claim 1 , wherein the substrate is held at a temperature of between about 100° C. and 350° C. during (a)-(c) and (d).

17. The method of claim 1 , wherein the dielectric film is silicon oxide doped with nitrogen, and wherein the concentration of oxygen in the dielectric film is between about 2-35 atomic percent and wherein the concentration of nitrogen in the dielectric film is between about 2-35 atomic percent.

18. The method of claim 1 , wherein the dielectric film is silicon oxide doped with carbon, and wherein the concentration of oxygen in the dielectric film is between about 2-35 atomic percent and wherein the concentration of carbon in the dielectric film is between about 2-35 atomic percent.

19. The method of claim 1 , further comprising:
applying photoresist to the substrate surface;
exposing the photoresist to light;
patterning the photoresist and transferring the pattern to the substrate surface; and
selectively removing the photoresist from the substrate surface.

20. The method of claim 1 , wherein:
forming the first nitrogen and/or carbon rich portion of the dielectric film stack further comprises one or more cycles of dielectric deposition performed prior to (d), each cycle comprising (a)-(c); and
forming the second nitrogen and/or carbon rich portion of the dielectric film stack further comprises one or more cycles of dielectric deposition performed prior to (d), each cycle comprising (a)-(c).

21. The method of claim 1 , further comprising:
depositing a third dielectric portion of the dielectric film stack after depositing the second nitrogen and/or carbon rich portion, by a process comprising two or more cycles of dielectric deposition, each cycle comprising (a)-(c); and
forming a third nitrogen and/or carbon rich portion of the dielectric film stack after depositing the third dielectric portion, by a process comprising (d);

wherein after deposition of the dielectric film stack, the nitrogen and/or carbon concentration in any of the first, second, or third nitrogen and/or carbon rich portions of the stack is greater than the nitrogen and/or carbon concentration in any of the first, second, or third dielectric portions of the stack.

22. The method of claim 21 , wherein:
forming the first nitrogen and/or carbon rich portion of the dielectric film stack further comprises one or more cycles of dielectric deposition performed prior to (d), each cycle comprising (a)-(c);
forming the second nitrogen and/or carbon rich portion of the dielectric film stack further comprises one or more cycles of dielectric deposition performe

Assignees

• Lavoie Adrien
• Sriram Mandyam
• Novellus Systems Inc

Inventors

• Lavoie Adrien
• Sriram Mandyam

Classifications

• H10P14/69433

  the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz · CPC title

• H10P14/69215

  the material being a silicon oxide, e.g. SiO2 · CPC title

• H10P14/6922

  the material containing Si, O and at least one of H, N, C, F or other non-metal elements, e.g. SiOC, SiOC:H or SiONC · CPC title

• H10P14/6538

  by exposure to UV light · CPC title

• H10P14/6339

  deposition by cyclic CVD, e.g. ALD, ALE or pulsed CVD · CPC title