CHEMICAL VAPOR DEPOSITION OF HIGH QUALITY FLOW-LIKE SILICON DIOXIDE USING A SILICON CONTAINING PRECURSOR AND ATOMIC OXYGEN

• US 20070281496A1
• Filed: 05/29/2007
• Published: 12/06/2007
• Est. Priority Date: 05/30/2006
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Yuan, Zheng, Gee, Paul, Sapre, Kedar, Ingle, Nitin
• Granted Patent: US 7,825,038 B2
• Time in Patent Office: Days
• US Class Current: 438/778
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02337 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/31612 on a silicon body

Abstract

Methods of depositing a silicon oxide layer on a substrate are described. The methods may include the steps of providing a substrate to a deposition chamber, generating an atomic oxygen precursor outside the deposition chamber, and introducing the atomic oxygen precursor into the chamber. The methods may also include introducing a silicon precursor to the deposition chamber, where the silicon precursor and the atomic oxygen precursor are first mixed in the chamber. The silicon precursor and the atomic oxygen precursor react to form the silicon oxide layer on the substrate, and the deposited silicon oxide layer may be annealed. Systems to deposit a silicon oxide layer on a substrate are also described.

Claims

1. A method of depositing a silicon oxide layer on a substrate, the method comprising:

providing a substrate to a deposition chamber;

generating an atomic oxygen precursor outside the deposition chamber, and introducing the atomic oxygen precursor into the chamber;

introducing a silicon precursor to the deposition chamber, wherein the silicon precursor and the atomic oxygen precursor are first mixed in the chamber;

reacting the silicon precursor and the atomic oxygen precursor to form the silicon oxide layer on the substrate; and

annealing the deposited silicon oxide layer.

2. The method of claim 1, wherein the substrate comprises a silicon wafer having a diameter of about 300 mm or less.

3. The method of claim 1, wherein a plurality of structures are formed on a surface of the substrate, wherein the structures include gaps and trenches having height to width aspect ratios of 7:

1 or more.

4. The method of claim 1, wherein the atomic oxygen precursor is formed by:

forming a plasma from a gas mixture comprising argon; and

introducing an oxygen precursor to the plasma, wherein the oxygen precursor dissociates to form the atomic oxygen.

5. The method of claim 4, wherein the oxygen precursor is selected from the group consisting of molecular oxygen, ozone, water vapor (H₂O), and nitrogen dioxide.

6. The method of claim 1, wherein the atomic oxygen precursor is formed by:

introducing an oxygen precursor into a photodissociation chamber; and

exposing the oxygen precursor to ultraviolet light, wherein the ultraviolet light dissociates the oxygen precursor to form atomic oxygen.

7. The method of claim 6, wherein the oxygen precursor is selected from the group consisting of molecular oxygen, ozone, and nitrogen dioxide.

8. The method of claim 1, wherein the silicon precursor is selected from the group consisting of silane, dimethylsilane, trimethylsilane, tetramethylsilane, diethylsilane, tetramethylorthosilicate (TMOS), tetraethylorthosilicate (TEOS), octamethyltrisiloxane (OMTS), octamethylcyclotetrasiloxane (OMCTS), tetramethyldimethyldimethoxydisilane, tetramethylcyclotetrasiloxane (TOMCATS), DMDMOS, DEMS, methyl triethoxysilane (MTES), phenyldimethylsilane, and phenylsilane.

9. The method of claim 1, wherein the silicon precursor is mixed with a carrier gas comprising helium.

10. The method of claim 1, wherein the deposition chamber comprises a wafer pedestal that supports substrate, wherein the substrate is adjusted by the wafer pedestal to a temperature of about 0°

C. to about 150°

C. as the silicon oxide layer is formed.

11. The method of claim 1, wherein the deposition chamber has a pressure of about 0.1 Torr to about 10 Torr as the silicon oxide layer is formed.

12. The method of claim 1, wherein the silicon oxide layer is formed at a rate of about 250 Å

/min to about 2 μ

m/min.

13. The method of claim 1, wherein the deposited silicon oxide annealing step comprises a thermal anneal, a steam anneal, a plasma anneal, an ultraviolet light anneal, an e-beam anneal, or a microwave anneal.

14. The method of claim 1, wherein the annealing of the deposited silicon oxide layer comprises:

heating the substrate at a first anneal temperature in the presence of steam; and

heating the substrate at a second anneal temperature in dry nitrogen.

15. The method of claim 14, wherein the first anneal temperature is up to about 950°

C. and the second anneal temperature is about 900°

C.

16. The method of claim 1, wherein the method comprises exposing the substrate to a pretreatment plasma before introducing the atomic oxygen precursor or silicon precursor to the deposition chamber.

17. The method of claim 16, wherein the pretreatment plasma is a high-density plasma comprising argon, helium, hydrogen (H₂), xenon, or ammonia.

18. The method of claim 1, wherein the deposition chamber is part of a high-density plasma chemical vapor deposition (HDPCVD) system.

19. A method of forming a silicon oxide layer on a substrate, the method comprising:

providing a silicon wafer substrate to a reaction chamber;

generating an atomic oxygen precursor from a dissociation of molecular oxygen in a high-density argon plasma, wherein the atomic oxygen precursor is generated in a remote plasma generating chamber that is external to the reaction chamber;

mixing the atomic oxygen precursor with a silicon precursor in the reaction chamber, wherein the atomic oxygen precursor and the silicon precursor are not mixed before reaching the reaction chamber; and

depositing the silicon oxide layer on the substrate, wherein the silicon oxide layer comprises reaction products from the reaction of the atomic oxygen with the silicon precursor.

20. The method of claim 19, wherein the method further comprises annealing the deposited silicon oxide layer.

21. The method of claim 20, wherein the deposited silicon oxide annealing step comprises a thermal anneal, a steam anneal, a plasma anneal, an ultraviolet light anneal, an e-beam anneal, or a microwave anneal.

22. The method of claim 19, wherein the silicon precursor is selected from the group consisting of silane, dimethylsilane, trimethylsilane, tetramethylsilane, diethylsilane, tetramethylorthosilicate (TMOS), tetraethylorthosilicate (TEOS), phenyldimethylsilane, and phenylsilane.

23. A system to deposit a silicon oxide layer on a substrate, the system comprising:

a deposition chamber in which the substrate is held;

a remote plasma generating system coupled to the deposition chamber, wherein the plasma generating system is used to generate an atomic oxygen precursor;

a silicon precursor source used to supply a silicon precursor to the deposition chamber; and

precursor handling system used to direct flows of the atomic oxygen precursor and the silicon precursor into the deposition chamber, wherein the precursor handling system keeps the atomic oxygen and silicon precursors from mixing before they enter the deposition chamber.

24. The system of claim 23, wherein the remote plasma generating system is a high-density plasma generating system.

25. The system of claim 24, wherein the system comprises an argon gas source and a molecular oxygen gas source coupled to the remote plasma generating system.

26. The system of claim 23, wherein a carrier gas from a carrier gas source is mixed with the silicon precursor before entering the deposition chamber.

27. The system of claim 23, wherein the precursor handling system comprises a first inlet and a second inlet formed in the deposition chamber, wherein the first and second inlets are positioned in an orthogonal direction to each other, and wherein the atomic oxygen precursor enters the chamber through the first inlet, and the silicon precursor enters the chamber through the second inlet.

28. The system of claim 23, wherein the system comprises an annealing system to anneal the silicon oxide layer.

29. The system of claim 28, wherein the annealing system comprises a thermal annealing system, a steam annealing system, a plasma annealing system, an ultraviolet light annealing system, an e-beam annealing system, or a microwave annealing system.

30. The method of claim 28, wherein the silicon oxide layer is annealed in the deposition chamber.

31. The method claim 23, wherein the system comprises a high-density plasma chemical vapor deposition (HDPCVD) system.