Method for depositing a coating having a relatively high dielectric constant onto a substrate

• US 20030031793A1
• Filed: 03/19/2002
• Published: 02/13/2003
• Est. Priority Date: 03/20/2001
• Status: Active Grant

• Current Assignee: Mattson Technology, Inc. (Beijing Economic & Technology Development Area), Regents of the University of California (University of California)
• Original Assignee: Mattson Technology, Inc. (Beijing Economic & Technology Development Area)
• Inventors: Levy, Sagy, Kepten, Avishai, Chang, Jane P., Lin, You-Sheng, Bloom, Robin, Sendler, Michael
• Granted Patent: US 6,884,719 B2
• Time in Patent Office: Days
• US Class Current: 427/255.28
• CPC Class Codes: C23C 16/40 Oxides
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• 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 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence
• CPC Class Codes: H01L 21/02148 the material containing hafnium, e.g. HfSiOx or HfSiON
• CPC Class Codes: H01L 21/02159 the material containing zirconium, e.g. ZrSiOx
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• CPC Class Codes: H01L 21/02183 the material containing tantalum, e.g. Ta2O5
• CPC Class Codes: H01L 21/02186 the material containing titanium, e.g. TiO2
• CPC Class Codes: H01L 21/02189 the material containing zirconium, e.g. ZrO2
• CPC Class Codes: H01L 21/02192 the material containing at least one rare earth metal element, e.g. oxides of lanthanides, scandium or yttrium
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/3141 Deposition using atomic layer deposition techniques [ALD]
• CPC Class Codes: H01L 21/31604 Deposition from a gas or vapour H01L21/31691, H01L21/31695 take precedence
• CPC Class Codes: H01L 21/31637 Deposition of Tantalum oxides, e.g. Ta2O5
• CPC Class Codes: H01L 21/31641 Deposition of Zirconium oxides, e.g. ZrO2
• CPC Class Codes: H01L 21/31645 Deposition of Hafnium oxides, e.g. HfO2

Abstract

A method for depositing a high-k dielectric coating onto a substrate, such as a semiconductor wafer, is provided. The substrate is subjected to one or more reaction cycles. For instance, in a typical reaction cycle, the substrate is heated to a certain deposition temperature. Thereafter, in one embodiment, one or more reactive organo-metallic gas precursors are supplied to the reactor vessel. An oxidizing gas is also supplied to the substrate at a certain oxidizing temperature to oxidize and/or densify the layers. As a result, a metal oxide coating is formed that has a thickness equal to at least about one monolayer, and in some instances, two or more monolayers. The dielectric constant of the resulting metal oxide coating is often greater than about 4, and in some instance, is from about 10 to about 80.

Claims

1. A method for depositing a dielectric coating onto a substrate comprising:

i) providing a system comprising a reactor vessel adapted to contain the substrate and an energy source in communication with said reactor vessel for heating the substrate contained in said vessel; and

ii) subjecting the substrate to a first reaction cycle, said first reaction cycle comprising;

a) heating the substrate to a first deposition temperature with said energy source, wherein said first deposition temperature is greater than about 300°

C.;

b) supplying to said reactor vessel a first gas precursor for a first deposition time period while the substrate is at said first deposition temperature, said first gas precursor having a first gas precursor flow rate, said first gas precursor comprising an organo-metallic compound;

c) supplying to said reactor vessel a first oxidizing gas for a first oxidizing gas time period while the substrate is at a first oxidizing gas temperature, said first oxidizing gas having a first oxidizing gas flow rate, wherein at least a partial monolayer of a dielectric is formed during the first reaction cycle; and

iii) subjecting the substrate to one or more additional reaction cycles to achieve a target thickness.

2. A method as defined in claim 1, wherein at least a monolayer is of the dielectric is formed during the first reaction cycle.

3. A method as defined in claim 1, wherein said first deposition temperature is greater than about 500°

C.

4. A method as defined in claim 1, wherein said first deposition temperature is from about 500°

C. to about 900°

C.

5. A method as defined in claim 1, wherein said first oxidizing gas temperature is greater than about 300°

C.

6. A method as defined in claim 1, wherein said first oxidizing gas temperature is from about 500°

C. to about 900°

C.

7. A method as defined in claim 1, further comprising:

subjecting the substrate to a second reaction cycle after said first reaction cycle, said second reaction cycle comprising;

a) supplying to said reactor vessel a second gas precursor for a second deposition time period while the substrate is at a second deposition temperature, said second deposition temperature being greater than about 300°

C., said second gas precursor having a second gas precursor flow rate;

b) supplying to said reactor vessel a second oxidizing gas for a second oxidizing gas time period while the substrate is at a second oxidizing gas temperature, said second oxidizing gas having a second oxidizing gas flow rate, wherein at least a partial monolayer of a dielectric is formed during the second reaction cycle.

8. A method as defined in claim 7, further comprising controlling the first reaction cycle and the second reaction cycle such that said first deposition temperature is different than said second deposition temperature, said first gas precursor flow rate is different than said second gas precursor flow rate, said first deposition time period is different than said second deposition time period, said first oxidizing gas temperature is different than said second oxidizing gas temperature, said first oxidizing gas flow rate is different than said second oxidizing gas flow rate, said first oxidizing gas time period is different than said second oxidizing gas time period, or combinations thereof.

9. A method as defined in claim 1, wherein the dielectric coating has a dielectric constant greater than about 8.

10. A method as defined in claim 1, wherein the dielectric coating has a dielectric constant from about 10 to about 80.

11. A method as defined in claim 1, wherein the dielectric coating contains a metal oxide.

12. A method as defined in claim 11, wherein said metal of said metal oxide coating is selected from the group consisting of aluminum, tantalum, titanium, zirconium, silicon, hafnium, yttrium, and combinations thereof.

13. A method as defined in claim 1, wherein the dielectric coating contains a metal silicate.

14. A method as defined in claim 1, wherein the substrate is a semiconductor wafer.

15. A method for depositing a dielectric coating onto a substrate comprising:

i) providing a system comprising a reactor vessel adapted to contain the substrate and an energy source in communication with said reactor vessel for heating the substrate contained in said vessel; and

ii) subjecting the substrate to a first reaction cycle, said first reaction cycle comprising;

a) heating the substrate to a first deposition temperature with said energy source, wherein said first deposition temperature is greater than about 300°

C.;

b) supplying to said reactor vessel a first gas precursor for a first deposition time period while the substrate is at said first deposition temperature, said first gas precursor having a first gas precursor flow rate, said first gas precursor comprising an organo-metallic compound;

c) supplying to said reactor vessel a first oxidizing gas for a first oxidizing gas time period while the substrate is at a first oxidizing gas temperature, said first oxidizing gas having a first oxidizing gas flow rate, wherein at least a partial monolayer of a dielectric is formed during the first reaction cycle; and

iii) subjecting the substrate to a second reaction cycle, said second reaction cycle comprising;

a) supplying to said reactor vessel a second gas precursor for a second deposition time period while the substrate is at a second deposition temperature, said second deposition temperature being greater than about 300°

C., said second gas precursor having a second gas precursor flow rate;

b) supplying to said reactor vessel a second oxidizing gas for a second oxidizing gas time period while the substrate is at a second oxidizing gas temperature, said second oxidizing gas having a second oxidizing gas flow rate, wherein at least a partial monolayer of a dielectric is formed during the second reaction cycle; and

iv) optionally, subjecting the substrate to one or more additional reaction cycles.

16. A method as defined in claim 15, wherein at least a monolayer of the dielectric is formed during the first reaction cycle, the second reaction cycle, or combinations thereof.

17. A method as defined in claim 15, wherein said first deposition temperature is from about 500°

C. to about 900°

C.

18. A method as defined in claim 16, wherein said first oxidizing gas temperature is from about 500°

C. to about 900°

C.

19. A method as defined in claim 15, further comprising controlling the first reaction cycle and the second reaction cycle such that said first deposition temperature is different than said second deposition temperature, said first gas precursor flow rate is different than said second gas precursor flow rate, said first deposition time period is different than said second deposition time period, said first oxidizing gas temperature is different than said second oxidizing gas temperature, said first oxidizing gas flow rate is different than said second oxidizing gas flow rate, said first oxidizing gas time period is different than said second oxidizing gas time period, or combinations thereof.

20. A method as defined in claim 15, wherein the dielectric coating has a dielectric constant greater than about 8.

21. A method as defined in claim 15, wherein the dielectric coating has a dielectric constant from about 10 to about 80.

22. A method as defined in claim 15, wherein the dielectric coating contains a metal oxide.

23. A method as defined in claim 22, wherein said metal of said metal oxide coating is selected from the group consisting of aluminum, tantalum, titanium, zirconium, silicon, hafnium, yttrium, and combinations thereof.

24. A method as defined in claim 15, wherein the dielectric coating contains a metal silicate.

25. A method as defined in claim 15, wherein the substrate is a semiconductor wafer.

26. A method for depositing a dielectric coating, said method comprising:

i) providing a system comprising a reactor vessel adapted to contain the semiconductor wafer and an energy source in communication with said reactor vessel for heating the semiconductor wafer contained in said vessel; and

ii) subjecting the semiconductor wafer to a first reaction cycle, said first reaction cycle comprising;

a) heating the semiconductor wafer to a first deposition temperature with said energy source, wherein said first deposition temperature is greater than about 300°

C.;

b) supplying to said reactor vessel a first gas precursor for a first deposition time period while the semiconductor wafer is at said first deposition temperature, said first gas precursor having a first gas precursor flow rate;

c) supplying to said reactor vessel a first oxidizing gas for a first oxidizing gas time period while the semiconductor wafer is at a first oxidizing gas temperature, said first oxidizing gas having a first oxidizing gas flow rate, wherein at least a partial monolayer of a dielectric is formed during the first reaction cycle; and

iii) subjecting the semiconductor wafer to a second reaction cycle, said second reaction cycle comprising;

a) supplying to said reactor vessel a second gas precursor for a second deposition time period while the semiconductor wafer is at a second deposition temperature, said second deposition temperature being greater than about 300°

C., said second gas precursor having a second gas precursor flow rate;

b) supplying to said reactor vessel a second oxidizing gas for a second oxidizing gas time period while the semiconductor wafer is at a second oxidizing gas temperature, said second oxidizing gas having a second oxidizing gas flow rate, wherein at least a partial monolayer of a dielectric is formed during the second reaction cycle; and

iv) optionally, subjecting the semiconductor wafer to one or more additional reaction cycles to achieve a target thickness;

wherein said first gas precursor, said second gas precursor, or combinations thereof is an organo-silicon compound so that the resulting dielectric coating contains a metal silicate.

27. A method as defined in claim 26, wherein at least a monolayer is formed during the first reaction cycle, the second reaction cycle, or combinations thereof.

28. A method as defined in claim 26, wherein said first deposition temperature is from about 500°

C. to about 900°

C.

29. A method as defined in claim 26, wherein said first oxidizing gas temperature is from about 500°

C. to about 900°

C.

30. A method as defined in claim 26, further comprising controlling the first reaction cycle and the second reaction cycle such that said first deposition temperature is different than said second deposition temperature, said first gas precursor flow rate is different than said second gas precursor flow rate, said first deposition time period is different than said second deposition time period, said first oxidizing gas temperature is different than said second oxidizing gas temperature, said first oxidizing gas flow rate is different than said second oxidizing gas flow rate, said first oxidizing gas time period is different than said second oxidizing gas time period, or combinations thereof.

31. A method as defined in claim 26, wherein said first gas precursor, said second gas precursor, or combinations thereof comprises an inorganic silicon compound.

32. A method as defined in claim 26, wherein the dielectric coating has a dielectric constant greater than about 8.

33. A method as defined in claim 26, wherein the dielectric coating has a dielectric constant from about 10 to about 80.

34. A method as defined in claim 26, wherein said metal silicate is selected from the group consisting of zirconium silicate, hafnium silicate, and combinations thereof.