Limited thermal budget formation of PMD layers

• US 7,431,967 B2
• Filed: 01/14/2004
• Issued: 10/07/2008
• Est. Priority Date: 09/19/2002
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Venkataraman, Shankar, Ingle, Nitin K., Yuan, Zheng, Wong, Shang, Ching, Cary, Mukai, Kevin Mikio
• Primary Examiner(s): Meeks; Timothy
• Assistant Examiner(s): GAMBETTA, KELLY M
• Application Number:
  US10/757,770
• Publication Number:
  US 20040166695A1
• Time in Patent Office: 1,728 Days
• Field of Search: 427/255.23, 427/255.26, 427/255.38, 438/738
• US Class Current: 427/255.28
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/45512 Premixing before introduction in the reaction chamber
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence
• CPC Class Codes: H01L 21/02129 the material being boron or phosphorus doped silicon oxides, e.g. BPSG, BSG or PSG
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• 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 21/31608 Deposition of SiO2 H01L21/31625, H01L21/31629 and H01L21/31633 take precedence
• CPC Class Codes: H01L 21/31625 Deposition of boron or phosphorus doped silicon oxide, e.g. BSG, PSG, BPSG
• CPC Class Codes: H01L 21/76837 Filling up the space between adjacent conductive structures; Gap-filling properties of dielectrics

Abstract

A method of filling a gap on a substrate includes providing flows of silicon-containing processing gas oxidizing processing gas, and phosphorous-containing processing gas to a chamber housing the substrate and depositing a first portion of a P-doped silicon oxide film as a substantially conformal layer in the gap by causing a reaction among the processing gases and varying over time a ratio of the gases. The temperature of the substrate is maintained below about 500° C. throughout deposition of the conformal layer. The method also includes depositing a second portion of the P-doped silicon oxide film as a bulk layer by maintaining the ratio of the gases substantially constant throughout deposition of the bulk layer. The temperature of the substrate is maintained below about 500° C. throughout deposition of the bulk layer.

Claims

1. A method of filling a gap defined by adjacent raised features on a substrate, comprising:

providing a flow of a silicon-containing processing gas to a chamber housing the substrate;

providing a flow of an oxidizing processing gas to the chamber;

providing a flow of a phosphorous-containing processing gas to the chamber;

depositing a first portion of a P-doped silicon oxide film as a substantially conformal layer in the gap by causing a reaction between the silicon-containing processing gas, the phosphorous-containing processing gas, and the oxidizing processing gas, wherein depositing the conformal layer comprises varying between a beginning and end of the depositing of the conformal layer, and throughout the depositing of the conformal layer a ratio of the (silicon-containing processing gas plus phosphorous-containing processing gas);

(oxidizing processing gas) and maintaining the temperature of the substrate below about 500°

C. throughout deposition of the conformal layer; and

thereafter, depositing a second portion of the P-doped silicon oxide film as a bulk layer, wherein depositing a second portion of the film comprises maintaining the ratio of the (silicon-containing processing gas plus phosphorous-containing processing gas);

(oxidizing processing gas) substantially constant throughout deposition of the bulk layer and maintaining the temperature of the substrate below about 500°

C. throughout deposition of the bulk layer.

2. The method of claim 1, further comprising:

thereafter, patterning metal lines on the substrate over the P-doped silicon oxide film; and

maintaining the temperature of the substrate below a reflow temperature of the P-doped silicon oxide film from a point in time immediately after deposition of the bulk layer to a point in time after patterning metal lines on the substrate.

3. The method of claim 2, wherein maintaining the temperature of the substrate below a reflow temperature of the P-doped silicon oxide film from a point in time immediately after deposition of the bulk layer to a point in time after patterning metal lines on the substrate comprises not annealing any portion of the substrate.

4. The method of claim 1, wherein the substrate comprises nickel silicide connectors and the P-doped silicon oxide film comprises a pre-metal dielectric layer.

5. A method of filling a gap defined by adjacent raised features on a substrate, comprising:

providing a flow of a silicon-containing processing gas to a chamber housing the substrate;

providing a flow of an oxidizing processing gas to the chamber;

depositing a first portion of a silicon oxide film as a substantially conformal layer in the gap by causing a reaction between the silicon-containing processing gas and the oxidizing processing gas, wherein depositing the conformal layer comprises varying between a beginning and end of the depositing of the conformal layer, and throughout the depositing of the conformal layer a ratio of the (silicon-containing processing gas);

(oxidizing processing gas) and maintaining the temperature of the substrate below about 500°

C. throughout deposition of the conformal layer;

thereafter, depositing a second portion of the silicon oxide film as a bulk layer, wherein depositing a second portion of the film comprises maintaining the ratio of the (silicon-containing processing gas);

(oxidizing processing gas) substantially constant throughout deposition of the bulk layer and maintaining the temperature of the substrate below about 500°

C. throughout deposition of the bulk layer; and

thereafter, depositing a cap layer comprising a P-doped silicon oxide film while maintaining the substrate below about 500°

C throughout deposition of the cap layer.

6. The method of claim 5, further comprising:

thereafter, patterning metal lines on the substrate over the P-doped silicon oxide film; and

maintaining the temperature of the substrate below a reflow temperature of either the silicon oxide film or the P-doped silicon oxide film from a point in time immediately after deposition of the bulk layer to a point in time after patterning metal lines on the substrate.

7. The method of claim 6, wherein maintaining the temperature of the substrate below a reflow temperature of either the silicon oxide film or the P-doped silicon oxide film from a point in time immediately after deposition of the bulk layer to a point in time after patterning metal lines on the substrate comprises not annealing any portion of the substrate.

8. A method of processing a semiconductor substrate, comprising:

providing a flow of a silicon-containing process gas to a chamber housing the substrate;

providing a flow of an oxidizer process gas to the chamber;

causing a reaction between the silicon-containing process gas and the oxidizing process gas to form a silicon oxide layer on the substrate;

varying throughout the deposition of a substantially conformal layer a ratio of the (silicon-containing gas);

(oxidizing gas) flowed into the chamber to alter a rate of deposition of the silicon oxide on the substrate between a beginning and end of the deposition of the substantially conformal layer; and

maintaining the substrate at or below a reflow temperature of the silicon oxide layer throughout processing of the semiconductor substrate.

9. The method of claim 8, wherein maintaining the substrate at or below a reflow temperature of the silicon oxide layer throughout processing of the semiconductor substrate comprises not annealing the substrate.

10. The method of claim 8, wherein the silicon oxide layer comprises a pre-metal dielectric layer.

11. The method of claim 8, wherein the substrate comprises a gap between adjacent surfaces, and wherein the silicon oxide is deposited in the gap.

12. The method of claim 8, wherein the substrate comprises nickel silicide.

13. The method of claim 8, further comprising providing a flow of a phosphorous-containing process gas to the chamber during a time period, wherein the flow of silicon-containing process gas is provided at least partly during the time period.

14. The method of claim 13, wherein the silicon-containing process gas comprises TEOS and wherein the phosphorous-containing process gas comprises TEPO.

15. The method of claim 13, further comprising:

thereafter providing a subsequent flow of phosphorous-containing process gas to the chamber.

16. The method of claim 15, further comprising, while providing the subsequent flow of phosphorous-containing process gas to the chamber, regulating a pressure of the chamber to a pressure in a range from about 200 torr to about 760 torr.

17. The method of claim 15, further comprising, while providing the subsequent flow of phosphorous-containing process gas to the chamber, forming a plasma from the phosphorous-containing process gas.

18. The method of claim 17, wherein the plasma has a density greater than about 1011 ions/cm3.

19. A method of processing a semiconductor substrate, comprising:

providing a flow of a silicon-containing process gas to a chamber housing the substrate;

providing a flow of an oxidizing process gas to the chamber;

providing a flow of a phosphorous-containing process gas to the chamber;

causing a reaction between the silicon-containing process gas, the oxidizing process gas, and the phosphorous-containing gas to form a P-doped silicon oxide layer on the substrate; and

varying throughout the deposition of a substantially conformal layer a ratio of the (silicon-containing gas);

(oxidizing gas);

(phosphorous-containing gas) flowed into the chamber to alter a rate of deposition of the silicon oxide on the substrate between a beginning and end of the deposition of the substantially conformal layer.

20. The method of claim 19, further comprising maintaining the substrate at or below at reflow temperature of the P-doped silicon oxide layer.

21. The method of claim 19, wherein the substrate comprises a gap between adjacent surfaces, and wherein the silicon oxide is deposited in the gap.

22. The method of claim 19, wherein the P-doped silicon oxide layer comprises a pre-metal dielectric layer.

23. The method of claim 19, wherein the substrate comprises nickel silicide.

24. The method of claim 19, wherein the silicon-containing process gas comprises TEOS and wherein the phosphorous-containing process gas comprises TEPO.

25. The method of claim 24, further comprising:

thereafter providing a subsequent flow of phosphorous-containing process gas to the chamber.

26. The method of claim 25, further comprising, while providing the subsequent flow of phosphorous-containing process gas to the chamber, regulating a pressure of the chamber to a pressure in a range from about 200 torr to about 760 torr.

27. The method of claim 25, further comprising, while providing the subsequent flow of phosphorous-containing process gas to the chamber, forming a plasma from the phosphorous-containing process gas.

28. The method of claim 27, wherein the plasma has a density greater than about 10¹¹ ions/cm³.