Method of manufacturing an oxynitride film for a semiconductor device

• US 9,196,473 B2
• Filed: 12/16/2011
• Issued: 11/24/2015
• Est. Priority Date: 12/27/2010
• Status: Active Grant

• Current Assignee: Kokusai Electric Corp.
• Original Assignee: Hitachi Kokusai Electric Incorporated (Hitachi, Ltd.)
• Inventors: Hirose, Yoshiro, Akae, Naonori, Takasawa, Yushin, Ota, Yosuke
• Primary Examiner(s): CHEN, BRET P
• Application Number:
  US13/976,673
• Publication Number:
  US 20130337660A1
• Time in Patent Office: 1,439 Days
• US Class Current: 1/1
• CPC Class Codes: C23C 16/308 Oxynitrides
• CPC Class Codes: C23C 16/45527 characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: C23C 16/45563 Gas nozzles
• CPC Class Codes: H01L 21/0214 the material being a silicon oxynitride, e.g. SiON or SiON:H
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD

Abstract

A method that includes: forming a specific element-containing layer by supplying a source gas to the substrate heated in a processing vessel, under a condition that a thermal decomposition reaction of the source gas is caused; changing the specific element-containing layer to a nitride layer by supplying a nitrogen-containing gas to the substrate; and changing the nitride layer to an oxynitride layer by supplying an oxygen-containing gas to the substrate, the source gas is sprayed in parallel to a surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in purging the inside of the processing vessel, by supplying an inert gas or a hydrogen-containing gas through the nozzle.

Claims

1. A method of manufacturing a semiconductor device, comprising:

forming an oxynitride film having a specific film thickness on a substrate by alternately repeating;

forming a specific element-containing layer on the substrate by supplying a source gas containing a specific element to the substrate heated in a processing vessel, under a condition that a thermal decomposition reaction of the source gas is caused;

changing the specific element-containing layer to a nitride layer by supplying a nitrogen-containing gas to the substrate heated in the processing vessel under a pressure of less than atmospheric pressure; and

changing the nitride layer to an oxynitride layer by supplying an oxygen-containing gas to the substrate heated in the processing vessel under a pressure of less than atmospheric pressure,

interposing into the above sequences, purging of an inside of the processing vessel by supplying an inert gas into the processing vessel,

wherein in forming the specific element-containing layer, the source gas and an inert gas, or the source gas and a hydrogen-containing gas are supplied to the substrate through a nozzle provided at a lateral side of the substrate, and at this time, the source gas is sprayed in parallel to a surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in purging the inside of the processing vessel, by setting a flow rate of the inert gas or the hydrogen-containing gas to a flow rate larger than a flow rate of the inert gas supplied in purging the inside of the processing vessel.

2. The method of claim 1, wherein in changing the nitride layer to the oxynitride layer, the nitride layer is oxidized without saturating an oxidation reaction of the nitride layer by the oxygen-containing gas.

3. The method of claim 1, wherein the oxygen-containing gas includes a nitrogen oxide-based gas.

4. The method of claim 1, wherein the oxygen-containing gas includes at least one of the gases selected from the group consisting of a N₂O gas, a NO gas, and a NO₂ gas.

5. The method of claim 1, wherein the oxygen-containing gas includes a N₂O gas.

6. The method of claim 1, wherein a temperature of the substrate in forming the oxynitride film having the specific film thickness, is set to 350°

C. or more and 950°

C. or less.

7. The method of claim 1, wherein a temperature of the substrate in forming the oxynitride film having the specific film thickness, is set to 700°

C. or more and 950°

C. or less.

8. The method of claim 1, wherein a temperature of the substrate in forming the oxynitride film having the specific film thickness, is set to 750°

C. or more and 950°

C. or less.

9. The method of claim 1, wherein a temperature of the substrate in forming the oxynitride film having the specific film thickness, is set to 800°

C. or more and 950°

C. or less.

10. The method of claim 1, wherein a source gas supply tube for supplying the source gas into the nozzle, is connected to the nozzle, and a supply tube for supplying the inert gas or the hydrogen-containing gas into the source gas supply tube, is connected to the source gas supply tube, the inert gas or the hydrogen-containing gas being supplied to the substrate together with the source gas through the nozzle.

11. The method of claim 1, wherein in forming the specific element-containing layer, the source gas is sprayed in parallel to the surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in purging the inside of the processing vessel, and more strongly than a case of spraying the nitrogen-containing gas in parallel to the surface of the substrate in changing the specific element-containing layer to the nitride layer.

12. The method of claim 1, wherein in forming the specific element-containing layer, the source gas is sprayed in parallel to the surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in purging the inside of the processing vessel, more strongly than a case of spraying the nitrogen-containing gas in parallel to the surface of the substrate in changing the specific element-containing layer to the nitride layer, and more strongly than a case of spraying the oxygen-containing gas in parallel to the surface of the substrate in changing the niride layer to the oxynitride layer.

13. The method of claim 1, wherein in forming the specific element-containing layer, the specific element-containing layer is formed while inhibiting deposition or adsorption of the specific element-containing layer onto the substrate by spraying the source gas in parallel to the surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in purging the inside of the processing vessel.

14. The method of claim 1, wherein in forming the specific element-containing layer, the specific element-containing layer is formed while inhibiting deposition or adsorption of the specific element-containing layer onto the substrate by spraying the source gas in parallel to the surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in purging the inside of the processing vessel, and at this time, a deposition center or an adsorption center of the specific element-containing layer is moved so as to be close to a center from an edge side of the substrate.

15. The method of claim 1, wherein the oxynitride film is formed as a gate insulating film.

16. The method of claim 15, further comprising forming a gate electrode on the oxynitride film.

17. The method of claim 1, wherein the oxynitride film is formed as a gate insulating film of a MOS capacitor.

18. A method of processing a substrate, comprising:

forming an oxynitride film having a specific film thickness on a substrate by alternately repeating;

forming a specific element-containing layer on the substrate by supplying a source gas containing a specific element to the substrate heated in a processing vessel, under a condition that a thermal decomposition reaction of the source gas is caused;

changing the specific element-containing layer to a nitride layer by supplying a nitrogen-containing gas to the substrate heated in the processing vessel under a pressure of less than atmospheric pressure; and

changing the nitride layer to an oxynitride layer by supplying an oxygen-containing gas to the substrate heated in the processing vessel under a pressure of less than atmospheric pressure;

interposing into the above sequences, purging of an inside of the processing vessel by supplying an inert gas into the processing vessel,

wherein in forming the specific element-containing layer, the source gas and an inert gas, or the source gas and a hydrogen-containing gas are supplied to the substrate through a nozzle provided at a lateral side of the substrate, and at this time, the source gas is sprayed in parallel to a surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in purging the inside of the processing vessel, by setting a flow rate of the inert gas or the hydrogen-containing gas to a flow rate larger than a flow rate of the inert gas supplied in purging the inside of the processing vessel.

19. A non-transitory computer-readable recording medium storing a program that causes a computer to perform a procedure of forming an oxynitride film having a specific film thickness on a substrate by alternately repeating:

a procedure of forming a specific element-containing layer on the substrate by supplying a source gas containing a specific element to the substrate heated in a processing vessel, under a condition that a thermal decomposition reaction of the source gas is caused;

a procedure of changing the specific element-containing layer to a nitride layer by supplying a nitrogen-containing gas to the substrate heated in the processing vessel under a pressure of less than atmospheric pressure; and

a procedure of changing the nitride layer to an oxynitride layer by supplying an oxygen-containing gas to the substrate heated in the processing vessel under a pressure of less than atmospheric pressure,

interposing into the above sequences, a procedure of purging an inside of the processing vessel by supplying an inert gas into the processing vessel,

wherein in the procedure of forming the specific element-containing layer, the source gas and an inert gas, or a the source gas and a hydrogen-containing gas are supplied to the substrate through a nozzle provided at a lateral side of the substrate, and at this time, the source gas is sprayed in parallel to a surface of the substrate more strongly than a case of spraying the inert gas in parallel to the surface of the substrate in the procedure of purging the inside of the processing vessel, by setting a flow rate of the inert gas or the hydrogen-containing gas to a flow rate larger than a flow rate of the inert gas supplied in the procedure of purging the inside of the processing vessel.