Method of forming oxynitride film

• US 10,559,458 B1
• Filed: 11/26/2018
• Issued: 02/11/2020
• Est. Priority Date: 11/26/2018
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM IP Holding B.V. (ASM International NV)
• Inventors: Suemori, Hidemi, Sekiguchi, Hiroo, Yoshida, Takashi
• Primary Examiner(s): Ahmed, Selim U
• Assistant Examiner(s): Clinton, Evan G
• Application Number:
  US16/200,100
• Time in Patent Office: 442 Days
• CPC Class Codes: C23C 16/308 Oxynitrides
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/45529 specially adapted for making a layer stack of alternating different compositions or gradient compositions
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: C23C 16/45538 Plasma being used continuously during the ALD cycle
• CPC Class Codes: C23C 16/4554 Plasma being used non-continuously in between ALD reactions C23C16/56 takes precedence
• CPC Class Codes: C23C 16/45542 Plasma being used non-continuously during the ALD reactions
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD
• CPC Class Codes: C23C 16/505 using radio frequency discharges
• CPC Class Codes: H01L 21/0214 the material being a silicon oxynitride, e.g. SiON or SiON:H
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02172 the material containing at least one metal element, e.g. metal oxides, metal nitrides, metal oxynitrides or metal carbides materials containing silicon H01L21/02123; metal silicates H01L21/02142
• CPC Class Codes: H01L 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• CPC Class Codes: H01L 21/02247 formation by nitridation, e.g. nitridation of the substrate
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02332 into an oxide layer, e.g. changing SiO to SiON

Abstract

A method of forming a nitrogen-incorporated silicon or metal oxide film, includes (i) depositing by a plasma a silicon or metal oxide film on a substrate using a precursor containing a silicon or metal and an oxidizing gas, said plasma having a first plasma density; and (ii) nitriding by a plasma the silicon or metal oxide film using a nitriding gas without using any precursor, said plasma having a second plasma density which is higher than the first plasma density.

Claims

1. A method of forming a nitrogen-incorporated silicon or metal oxide film, comprising steps of:

(i) depositing by a plasma a silicon or metal oxide film on a substrate using a precursor containing a silicon or metal and an oxidizing gas, said plasma having a first plasma density; and

(ii) nitriding by a plasma the silicon or metal oxide film using a nitriding gas without using any precursor, said plasma having a second plasma density which is higher than the first plasma density.

2. The method according to claim 1, further comprising, prior to step (i), (ii) nitriding by a plasma a surface of the substrate using a nitriding gas without using any precursor.

3. The method according to claim 1, wherein in step (i), the silicon or metal oxide film is deposited by plasma-enhanced atomic layer deposition (PEALD).

4. The method according to claim 3, wherein the oxidizing gas contains both oxygen and nitrogen.

5. The method according to claim 3, wherein in step (i), the plasma is a capacitively coupled plasma generated by applying RF power to electrodes, wherein a duration of RF power is 2.0 seconds or less in each cycle of PEALD and a power of RF power is 0.28 W per cm² of the substrate surface or less.

6. The method according to claim 5, wherein in step (ii), the plasma is generated by applying RF power to the electrodes, wherein a power of RF power is 0.42 W per cm² of the substrate surface or higher.

7. The method according to claim 1, wherein step (i) and step (ii) are conducted in a same reaction space or different reaction spaces to which an inert gas is supplied through steps (i) and (ii).

8. The method according to claim 7, wherein in step (ii), a flow ratio of the nitriding gas to the inert gas is 1/99 to 50/50.

9. The method according to claim 3, wherein step (ii) is repeatedly conducted after every one to 100 cycles of PEALD.

10. The method according to claim 1, wherein the substrate has a recess pattern and the silicon or metal oxide film is conformally deposited on the recess pattern.

11. The method according to claim 3, wherein in step (i), the plasma is an inductively coupled plasma generated by applying RF power to electrodes or a remote plasma generated in a remote plasma unit.

12. A method of forming a nitrogen-incorporated silicon or metal oxide film by converting a silicon or metal oxide film to a silicon or metal oxynitride film at a desired location, comprising steps of:

(a) designing a layer structure of a nitrogen-incorporated silicon or metal oxide film, which layer structure is composed of a layer A constituted by a silicon or metal oxide film and a layer B constituted by a silicon or metal oxynitride film;

(b) according to the design, depositing, for the layer A, by a plasma the silicon or metal oxide film on a substrate using a precursor containing a silicon or metal and an oxidizing gas, said plasma having a first plasma density; and

(c) according to the design, nitriding, for the layer B, by a plasma the silicon or metal oxide film using a nitriding gas without using any precursor in a manner converting the silicon or metal oxide film to the silicon or metal oxynitride film, said plasma having a second plasma density which is higher than the first plasma density.

13. The method according to claim 12, wherein the nitrogen-incorporated silicon or metal oxide film is constituted by multiple layers of the layer A and multiple layers of the layer B, alternately layered.

14. The method according to claim 12, wherein a ratio of a total thickness of the layer A to a total thickness of the layer B is 0/100 to 99/1.

15. A method of forming an oxygen-incorporated silicon or metal nitride film, comprising steps of:

(i) depositing by a plasma a silicon or metal nitride film on a substrate using a precursor containing a silicon or metal and a nitriding gas, said plasma having a first plasma density; and

(ii) oxidizing by a plasma the silicon or metal nitride film using an oxidizing gas without using any precursor, said plasma having a second plasma density which is lower than the first plasma density.

16. A method of forming an element X-incorporated silicon or metal oxide film, comprising steps of:

(i) depositing by a plasma a silicon or metal oxide film on a substrate using a precursor containing a silicon or metal and an oxidizing gas, said plasma having a first plasma density; and

(ii) exciting an element X-containing gas by a plasma and incorporating the element X into the silicon or metal oxide film without using any precursor for deposition, said plasma having a second plasma density which is higher than the first plasma density.

17. The method according to claim 16, wherein the element X is selected from the group consisting of B, C, Al, P, S, Ga, and As.