SYSTEMS AND METHODS FOR THIN-FILM DEPOSITION OF METAL OXIDES USING EXCITED NITROGEN-OXYGEN SPECIES

• US 20110070380A1
• Filed: 08/11/2010
• Published: 03/24/2011
• Est. Priority Date: 08/14/2009
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM America Incorporated (ASM International NV)
• Inventors: Raisanen, Petri I., Wang, Chang-Gong, Jung, Sung Hoon, Shero, Eric
• Granted Patent: US 8,883,270 B2
• Time in Patent Office: Days
• US Class Current: 427/569
• CPC Class Codes: C01B 13/11 by electric discharge
• CPC Class Codes: C01B 2201/64 Oxygen
• CPC Class Codes: C23C 16/40 Oxides
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence

Abstract

Systems and methods are delineated which, among other things, are for depositing a film on a substrate that is within a reaction chamber. In an exemplary method, the method may comprise applying an atomic layer deposition cycle to the substrate, wherein the cycle may comprise exposing the substrate to a precursor gas for a precursor pulse interval and then removing the precursor gas thereafter, and exposing the substrate to an oxidizer comprising an oxidant gas and a nitrogen-containing species gas for an oxidation pulse interval and then removing the oxidizer thereafter. Aspects of the present invention utilize molecular and excited nitrogen-oxygen radical/ionic species in possible further combination with oxidizers such as ozone. Embodiments of the present invention also include electronic components and systems that include devices fabricated with methods consistent with the present invention.

Claims

1. A method for depositing a film on a substrate that is within a reaction chamber, the method comprising applying an atomic layer deposition cycle to the substrate, the cycle comprising:

exposing the substrate to a precursor gas for a precursor pulse interval then removing the precursor gas thereafter; and

exposing the substrate to an oxidizer comprising an oxidant gas and a nitrogen-containing species gas for an oxidation pulse interval then removing the oxidizer thereafter.

2. The method of claim 1 wherein the precursor gas comprises a rare earth metal selected from the group consisting of Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof.

3. The method of claim 1 wherein the precursor gas comprises at least one of an organo-metallic and a metal halide compound.

4. The method of claim 1 wherein the precursor gas comprises at least one of:

hafnium tetrachloride (HfCl₄);

titanium tetrachloride (TiCl₄);

tantalum pentachloride (TaCl₅);

tantalum pentafluoride (TaF₅);

zirkonium tetrachloride (ZrCl₄);

rare earth betadiketonate compounds including (La(THD)₃) and (Y(THD)₃);

rare earth cyclopentadienyl (Cp) compounds including La(iPrCp)₃;

rare earth amidinate compounds including lanthanum tris-formamidinate La(FAMD)₃;

cyclooctadienyl compounds including rare earth metals;

alkylamido compounds including;

tetrakis-ethyl-methylamino hafnium (TEMAHf);

tetrakis (diethylamino) hafnium ((Et₂N)₄Hf or TDEAH); and

tetrakis (dimethylamino) hafnium ((Me₂N)₄Hf or TDMAH);

alkoxides;

halide compounds of silicon;

silicon tetrachloride;

silicon tetrafluoride; and

silicon tetraiodide.

5. The method of claim 1 wherein the oxidant gas is the nitrogen-containing species gas.

6. The method of claim 1 wherein the nitrogen-containing species gas including activated ionic or radical species including at least one of NO*, N₂O*, NO₂*, NO₃*, and N₂O₅*.

7. The method of claim 1 wherein the oxidant gas comprises ozone and one or more gasses selected from the group consisting of O, O₂, NO, N₂O, NO₂, NO₃, N₂O₅, an NxOy radical species, an NxOy ionic species, and combinations thereof.

8. The method of claim 7 wherein the oxidant gas comprises approximately 5 atomic percent to 25 atomic percent O₃.

9. The method of claim 7 wherein O₃ is produced from O₂ and a nitrogen source gas wherein a mixture of the O₂ and nitrogen source gas is subjected to a plasma discharge.

10. The method of claim 9 wherein the nitrogen source gas is at least one of N₂, NO, N₂O, NO₂, NO₃, and N₂O₅.

11. The method of claim 1 wherein the nitrogen-containing species gas comprises an excited N_xO_y radical species, an excited N_xO_y ionic species, and combinations thereof.

12. The method of claim 1 wherein oxidant gas comprises a mixture of two or more of O, O₂, NO, N₂O, NO₂, NO₃, N₂O₅, NO, N_xO_y, radicals thereof, and O₃, and wherein the mixture comprises approximately 5 atomic percent to 25 atomic percent O₃.

13. The method of claim 10 wherein flow ratio of N₂/O₂ is >

0.001.

14. The method of claim 10 wherein the ratio of the O₂ and the nitrogen source gas determine at least one of:

an amount of a nitrogen-containing species gas comprising activated ionic or radical species including at least one of NO*, N₂O*, NO₂*, NO₃*, and N₂O₅*;

a concentration of a nitrogen-containing species gas comprising activated ionic or radical species including at least one of NO*, N₂O*, NO₂*, NO₃*, and N₂O₅*;

a growth rate of the deposited film;

a film uniformity across the substrate;

a dielectric constant of the deposited film;

an index of refraction of the deposited film; and

a molecular composition of the deposited film.

15. The method of claim 10 wherein a power input controls the plasma, and an amount of power delivered to the plasma determine at least one of:

an amount of a nitrogen-containing species gas comprising activated ionic or radical species including at least one of NO*, N2O*, NO2*, NO3*, and N2O5*;

a concentration of a nitrogen-containing species gas comprising activated ionic or radical species including at least one of NO*, N2O*, NO2*, NO3*, and N2O5*;

a growth rate of the deposited film;

a film uniformity across the substrate;

a dielectric constant of the deposited film;

an index of refraction of the deposited film; and

a molecular composition of the deposited film.

16. The method of claim 10 further comprising:

generating the oxidizer by exposing O₂ and a nitrogen source gas to a plasma discharge;

monitoring a ratio of O₃ and excited N_xO_y species generated by the plasma discharge; and

adjusting at least one of a power input to the plasma discharge, a temperature of a housing;

a flow rate of the O₂, and a flow rate of the nitrogen source gas to achieve a predetermined criterion.

17. The method of claim 16 wherein the predetermined criterion includes at least one of:

an oxidizer flow rate;

an oxidant/N_xO_y concentration ratio;

an active N_xO_y species concentration;

a ratio of active N_xO_y species, wherein the excited N_xO_y species gas contains a plurality of excited nitrogen-oxygen compounds; and

a concentration of a particular active nitrogen-oxygen compound.

18. The method of claim 1 further comprising:

exposing the substrate to a second precursor gas for a second precursor pulse interval then removing the second precursor gas thereafter; and

after removing the second precursor gas, exposing the substrate to an oxidizer comprising an oxidant gas and a nitrogen-containing species gas for a oxidation pulse interval then removing the oxidizer thereafter.

23. A system comprising:

a reaction chamber;

a precursor reactant source coupled to the reactor chamber;

a purge gas source coupled to the reactor chamber;

an oxidant source coupled to the reactor chamber;

an excited nitrogen species source coupled to the reactor chamber;

and a system operation and control mechanism wherein the system is configured to perform the steps of the method of claim 1, and all claims dependent thereon, whether disjointly or in combination.

19. A method comprising depositing a metal oxide at least one of in any film stack using a metal halide precursor and an oxidant comprising ozone and excited nitrogen-oxygen species.

20. The method of claim 19 wherein the metal oxide comprises at least one of Al₂O₃, HfO₂, ZrO₂, La₂O₃ and Ta₂O₅.

21. The method of claim 19 wherein the metal halide comprises any metal in compound combination with any halide element.

22. A method for depositing a film on a substrate comprising controlling uniformity of deposition of the deposited film by adjusting an amount of an active nitrogen-oxygen species exposed to the substrate.