METHOD OF FORMING CRYSTALLOGRAPHICALLY STABILIZED DOPED HAFNIUM ZIRCONIUM BASED FILMS

• US 20080233288A1
• Filed: 03/20/2007
• Published: 09/25/2008
• Est. Priority Date: 03/20/2007
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Clark, Robert D.
• Granted Patent: US 7,833,913 B2
• Time in Patent Office: Days
• US Class Current: 427/255.394
• CPC Class Codes: C23C 16/308 Oxynitrides
• CPC Class Codes: C23C 16/34 Nitrides C23C16/303 takes precedence
• CPC Class Codes: C23C 16/405 of refractory metals or yttrium
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: C23C 16/45536 Use of plasma, radiation or electromagnetic fields
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD

Abstract

A method is provided for forming doped hafnium zirconium based films by atomic layer deposition (ALD) or plasma enhanced ALD (PEALD). The method includes disposing a substrate in a process chamber and exposing the substrate to a gas pulse containing a hafnium precursor, a gas pulse containing a zirconium precursor, and a gas pulse containing one or more dopant elements. The dopant elements may be selected from Group II, Group XIII, silicon, and rare earth elements of the Periodic Table. Sequentially after each precursor and dopant gas pulse, the substrate is exposed to a gas pulse containing an oxygen-containing gas, a nitrogen-containing gas, or an oxygen- and nitrogen-containing gas. In alternative embodiments, the hafnium and zirconium precursors may be pulsed together, and either or both may be pulsed with the dopant elements. The sequential exposing steps may be repeated to deposit a doped hafnium zirconium based film with a predetermined thickness.

Claims

1. A method of processing a substrate, comprising:

disposing the substrate in a process chamber; and

exposing the substrate to a gas pulse sequence to deposit a doped hafnium zirconium based film with a predetermined thickness, wherein the gas pulse sequence includes, in any order;

a) sequentially first, exposing the substrate to a gas pulse comprising a hafnium precursor, and second, exposing the substrate to a gas pulse comprising an oxygen-containing gas, a nitrogen-containing gas, or an oxygen- and nitrogen-containing gas;

b) sequentially first, exposing the substrate to a gas pulse comprising a zirconium precursor, and second, exposing the substrate to a gas pulse comprising the oxygen-containing gas, the nitrogen-containing gas, or the oxygen- and nitrogen-containing gas; and

c) sequentially first, exposing the substrate to a gas pulse comprising one or more dopant elements selected from Group II, Group XIII, silicon, and rare earth elements of the Periodic Table, and second, exposing the substrate to a gas pulse comprising the oxygen-containing gas, the nitrogen-containing gas, or the oxygen- and nitrogen-containing gas,

wherein each of a), b), and c) are alternatingly performed, any number of desired times to achieve the predetermined thickness.

2. The method of claim 1, wherein the dopant elements are selected from Be, Mg, Ca, Sr, Ba, Ra, B, Al, Ga, In, TI, Si, Y, Lu, La, Ce, Pr, Nd, Sm, Eu, Gd, The Dy, Ho, Er, Tm, and Yb.

3. The method of claim 1, wherein the oxygen-containing gas comprises O₂, H₂O, H₂O₂, ozone, or plasma excited oxygen, or a combination of two or more thereof.

4. The method of claim 1, wherein the nitrogen-containing gas comprises NH₃, N₂H₄, C₁-C₁₀ alkylhydrazine compounds, or plasma excited nitrogen, or a combination thereof.

5. The method of claim 1, wherein the oxygen- and nitrogen-containing gas comprises NO, NO₂, or N₂O, or a combination thereof.

6. The method of claim 1, wherein a) comprises:

alternating the first and second exposing steps a plurality of times.

7. The method of claim 1, wherein b) comprises:

alternating the first and second exposing steps a plurality of times.

8. The method of claim 1, wherein c) comprises:

alternating the first and second exposing steps a plurality of times.

9. The method of claim 1, further comprising purging or evacuating the process chamber after at least one of a), b) or c).

10. The method of claim 1, further comprising purging or evacuating the process chamber between the first and second exposing steps in at least one of a), b) or c).

11. The method of claim 1, further comprising:

sequentially first exposing the substrate to a gas pulse comprising the hafnium or the zirconium precursors with the one or more dopant elements by performing the first exposing steps in a) or b) concurrently with the first exposing step in c); and

second expose the substrate to a gas pulse comprising the oxygen-containing gas, the nitrogen-containing gas, or the oxygen- and nitrogen-containing gas by performing the second exposing steps in a) or b) concurrently with the second exposing step in c).

12. The method of claim 11, further comprising alternating a plurality of times the first exposing the substrate to a gas pulse comprising the hafnium or the zirconium precursors with the one or more dopant elements, and the second exposing the substrate to a gas pulse comprising the oxygen-containing gas, the nitrogen-containing gas, or the oxygen- and nitrogen-containing gas.

13. The method of claim 1, further comprising:

sequentially first exposing the substrate to a gas pulse comprising both the hafnium and zirconium precursors by performing the first exposing steps in a) and b) concurrently; and

second exposing the substrate to a gas pulse comprising the oxygen-containing gas, the nitrogen-containing gas, or the oxygen- and nitrogen-containing gas by performing the second exposing steps in a) and b) concurrently.

14. The method of claim 13, further comprising alternating a plurality of times the first exposing the substrate to a gas pulse comprising the hafnium and the zirconium precursors, and the second exposing the substrate to a gas pulse comprising the oxygen-containing gas, the nitrogen-containing gas, or the oxygen- and nitrogen-containing gas.

15. The method of claim 1, further comprising:

exposing the deposited doped hafnium zirconium based film to ozone, plasma excited oxygen, or plasma excited nitrogen, or a combination thereof.

16. A method processing a substrate, comprising:

a) disposing the substrate in a process chamber;

b) exposing the substrate to a gas pulse comprising hafnium and zirconium precursors and one or more dopant elements selected from Group II, Group XIII, silicon, and rare earth elements of the Periodic Table; and

c) exposing the substrate to a gas pulse containing an oxygen-containing gas, a nitrogen-containing gas, or an oxygen- and nitrogen-containing gas.

17. The method of claim 16, wherein the dopant elements are selected from Be, Mg, Ca, Sr, Ba, Ra, B, Al, Ga, In, TI, Si, Y, Lu, La, Ce, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, and Yb.

18. The method of claim 16, wherein the oxygen-containing gas comprises O₂, H₂O, H₂O₂, ozone, or plasma excited oxygen, or a combination of two or more thereof.

19. The method of claim 16, wherein the nitrogen-containing gas comprises NH₃, N₂H₄, C₁-C₁₀ alkylhydrazine compounds, or plasma excited nitrogen, or a combination thereof.

20. The method of claim 16, wherein the oxygen- and nitrogen-containing gas comprises NO, NO₂, or N₂O, or a combination thereof.

21. The method of claim 16, further comprising purging or evacuating the process chamber after at least one of the exposing steps.

22. The method of claim 16, further comprising:

exposing the deposited doped hafnium zirconium based film to ozone, plasma excited oxygen, or plasma excited nitrogen, or a combination thereof.

23. The method of claim 16, further comprising:

d) repeating steps b)-c) a predetermined number of times to deposit a doped hafnium zirconium based film with a desired thickness.

24. The method of claim 16, wherein the steps b) and c) are performed concurrently for a predetermined time after step a) to deposit a doped hafnium zirconium based film with a desired thickness.