Method of depositing dielectric materials in damascene applications

• US 20050233576A1
• Filed: 04/28/2005
• Published: 10/20/2005
• Est. Priority Date: 12/14/2001
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Xia, Li-Qun, Venkataraman, Shankar, Nemani, Srinivas D., Xu, Ping, Han, Fei, Yieh, Ellie, Zheng, Yi, Lee, Ju-Hyung, Moghadam, Farhad K., Sinha, Ashok K., Yim, Kangsub
• Granted Patent: US 7,151,053 B2
• Time in Patent Office: Days
• US Class Current: 438/623
• CPC Class Codes: C23C 16/30 Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02126 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 Class Codes: H01L 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• CPC Class Codes: H01L 21/02216 the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02304 formation of intermediate layers, e.g. buffer layers, layers to improve adhesion, lattice match or diffusion barriers
• CPC Class Codes: H01L 21/31138 by dry-etching
• CPC Class Codes: H01L 21/31144 using masks
• CPC Class Codes: H01L 21/312 Organic layers, e.g. photoresist H01L21/3105, H01L21/32 take precedence; photoresists per se G03C
• CPC Class Codes: H01L 21/3122 layers comprising polysiloxane compounds
• CPC Class Codes: H01L 21/3127 Layers comprising fluoro (hydro)carbon compounds, e.g. polytetrafluoroethylene
• CPC Class Codes: H01L 21/31633 Deposition of carbon doped silicon oxide, e.g. SiOC
• CPC Class Codes: H01L 21/76807 for dual damascene structures
• CPC Class Codes: H01L 21/7681 involving one or more buried masks
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76828 thermal treatment
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
• CPC Class Codes: H01L 21/76834 formation of thin insulating films on the sidewalls or on top of conductors H01L21/76831 takes precedence

Abstract

Methods are provided for depositing an oxygen-doped dielectric layer. The oxygen-doped dielectric layer may be used for a barrier layer or a hardmask. In one aspect, a method is provided for processing a substrate including positioning the substrate in a processing chamber, introducing a processing gas comprising an oxygen-containing organosilicon compound, carbon dioxide, or combinations thereof, and an oxygen-free organosilicon compound to the processing chamber, and reacting the processing gas to deposit an oxygen-doped dielectric material on the substrate, wherein the dielectric material has an oxygen content of about 15 atomic percent or less. The oxygen-doped dielectric material may be used as a barrier layer in damascene or dual damascene applications.

Claims

1. A method for processing a substrate, comprising:

positioning a substrate in a processing chamber;

introducing a processing gas comprising a compound comprising oxygen and carbon and an oxygen-free organosilicon compound; and

generating a plasma of the processing gas by applying a mixed frequency RF power to deposit an oxygen-doped silicon carbide layer on the substrate.

2. The method of claim 1, wherein the compound comprising oxygen and carbon has the formula C_xH_yO_z, with X being between 0 and 2, Y being between 0 and 2, and Z being between 1 and 3, wherein X+Y is at least 1 and X+Y+Z is 3 or less.

3. The method of claim 2, wherein the compound comprising oxygen and carbon is selected from the group consisting of carbon dioxide, carbon monoxide, and combinations thereof.

4. The method of claim 1, wherein the oxygen-free organosilicon compound comprises an organosilane compound selected from the group consisting of methylsilane, dimethylsilane, trimethylsilane, ethylsilane, disilanomethane, bis(m-ethylsilano)methane, 1,2-disilanoethane, 1,2-bis(methylsilano)ethane, 2,2-disilanopropane, 1,3,5-trisilano-2,4,6-trimethylene, and combinations thereof.

5. The method of claim 1, wherein the mixed frequency RF power comprises a first frequency between 13 MHz and 14 MHz and a second frequency RF power is between 100 KHz and 1 MHz.

6. The method of claim 5, wherein the first frequency RF power is about 13.56 MHz and the second frequency RF power is about 356 KHz.

7. The method of claim 5, wherein the mixed frequency RF power is provided in a continuous cycle.

8. The method of claim 5, wherein the mixed frequency RF power is provided in a cycle of a short duration wherein the power is on at a stated level for an on cycle less than about 200 Hz and the on cycles total between about 10% and about 30% of a total cycle.

9. The method of claim 5, wherein the mixed frequency RF power is between about 10 watts and 1000 watts.

10. The method of claim 1, wherein the processing gas further comprises an inert gas selected from the group consisting of helium, argon, neon, xenon, krypton or combinations thereof.

11. The method of claim 1, further comprising exposing the substrate to a plasma of a reducing gas selected from the group consisting of hydrogen, ammonia or combinations thereof.

12. The method of claim 1, further comprising exposing the substrate to a plasma of an inert gas selected from the group consisting of helium, argon, neon, xenon, krypton or combinations thereof.

13. The method of claim 1, wherein the compound comprising oxygen and carbon is carbon dioxide, the oxygen-free organosilicon compound is trimethylsilane, and the inert gas is helium.

14. The method of claim 1, further comprising:

depositing a first dielectric layer on the oxygen-doped silicon carbide layer;

depositing a second oxygen-doped silicon layer on the first dielectric layer; and

then

etching feature definitions in the second oxygen-doped silicon carbide layer to expose the first dielectric layer.

15. A method for processing a substrate comprising:

positioning a substrate in a processing chamber;

introducing a processing gas comprising a compound comprising oxygen and carbon and an oxygen-free organosilicon compound;

generating a plasma of the processing gas by applying a mixed frequency RF power comprising a first frequency RF power is between 13 MHz and 14 MHz and a second frequency RF power is between 100 KHz and 1 MHz at a power density between about 0.03 watts/cm² and about 1500 watts/cm² to deposit an oxygen-doped silicon carbide layer on the substrate; and

exposing the deposited oxygen doped-silicon carbide layer to an in situ plasma of an inert gas.

16. The method of claim 15, wherein the inert gas selected from the group consisting of helium, argon, neon, xenon, krypton or combinations thereof.

17. The method of claim 15, wherein the mixed frequency RF power is between about 10 watts and 1000 watts.

18. The method of claim 17, wherein the mixed frequency RF power is provided in a continuous cycle or the mixed frequency RF power is provided in a cycle of a short duration wherein the power is on at a stated level for an on cycle less than about 200 Hz and the on cycles total between about 10% and about 30% of a total cycle.

19. The method of claim 15, wherein the compound comprising oxygen and carbon has the formula C_xH_yO_z, with X being between 0 and 2, Y being between 0 and 2, and Z being between 1 and 3, wherein X+Y is at least 1 and X+Y+Z is 3 or less.

20. The method of claim 19, wherein the compound comprising oxygen and carbon is selected from the group consisting of carbon dioxide, carbon monoxide, water, and combinations thereof.

21. The method of claim 19, wherein the processing gas further comprises an inert gas selected from the group consisting of helium, argon, neon, xenon, krypton or combinations thereof.

22. The method of claim 20, wherein the compound comprising oxygen and carbon is carbon dioxide, the oxygen-free organosilicon compound is trimethylsilane, and the inert gas is helium.

23. The method of claim 15, wherein the mixed frequency RF power comprises a first frequency RF power between 13 MHz and 14 MHz and a second frequency RF power between 100 KHz and 1 MHz.