Process for low temperature atomic layer deposition of RH

• US 6,943,073 B2
• Filed: 10/30/2002
• Issued: 09/13/2005
• Est. Priority Date: 06/21/2001
• Status: Expired due to Fees

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Uhlenbrock, Stefan, Marsh, Eugene P.
• Primary Examiner(s): TRINH, MICHAEL MANH
• Application Number:
  US10/283,316
• Publication Number:
  US 20030054606A1
• Time in Patent Office: 1,049 Days
• Field of Search: 438/210, 438/240, 438/239, 438/253, 438/386, 438/393, 438/396, 438/680, 438/686
• US Class Current: 438/210
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/16 from metal carbonyl compounds
• CPC Class Codes: C23C 16/18 from metallo-organic compounds
• CPC Class Codes: C23C 16/4401 Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD
• CPC Class Codes: H01L 28/55 with a dielectric comprising a perovskite structure material
• CPC Class Codes: H01L 28/60 Electrodes
• CPC Class Codes: H01L 28/65 comprising a noble metal or a noble metal oxide, e.g. platinum (Pt), ruthenium (Ru), ruthenium dioxide (RuO2), iridium (Ir), iridium dioxide (IrO2)
• CPC Class Codes: H10B 12/033 the capacitor extending over the transistor
• CPC Class Codes: H10B 12/312 with a bit line higher than the capacitor

Abstract

A method for the formation of rhodium films with good step coverage is disclosed. Rhodium films are formed by a low temperature atomic layer deposition technique using a first gas of rhodium group metal precursor followed by an oxygen exposure. The invention provides, therefore, a method for forming smooth and continuous rhodium films which also have good step coverage and a reduced carbon content.

Claims

1. A method of forming a capacitor comprising the steps of:

forming a first and second electrode;

forming a dielectric layer between said first and second electrode; and

wherein at least one of said first and second electrode is formed by conducting atomic layer deposition of a rhodium group metal precursor in a deposition chamber and introducing oxygen into said deposition chamber to obtain a substantially pure metallic rhodium layer.

2. The method of claim 1, wherein said rhodium group metal precursor comprises an organic rhodium group metal precursor having the formula Ly[Rh]Yz, wherein L is independently selected from the group consisting of neutral and anionic ligands;

y is one of {1, 2, 3, 4};

Y is independently a pi-orbital bonding ligand selected from the group consisting of CO, NO, CN, CS, N₂, PX₃, PR₃, P(OR)₃, AsX₃, AsR₃, As(OR)₃, SbX₃, SbR₃, Sb(OR)₃, NHxR_3-x, CNR, and RCN, wherein R is an organic group, X is a halide and x is one of {0, 1, 2, 3}; and

z is one of {0, 1, 2, 3, 4}.

3. The method of claim 2, wherein said rhodium group metal precursor is dicarbonyl cyclopentadienyl rhodium.

4. The method of claim 1, wherein said atomic layer deposition is performed at a temperature of about 100°

C. to about 200°

C.

5. The method of claim 1, wherein said rhodium group metal precursor is introduced into a reactor chamber at a rate of about 0.1 about 500 sccm.

6. The method of claim 1, wherein said rhodium group metal precursor is introduced into said reactor chamber at a rate of about 0.1 to about 5 sccm.

7. The method of claim 1, wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 500 sccm.

8. The method of claim 7, wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 200 sccm.

9. The method of claim 7, further comprising introducing a first gas into said reactor chamber after said step of introducing said rhodium group metal precursor and before said step of introducing oxygen.

10. The method of claim 9, wherein said first as is selected from the group consisting of helium, argon and nitrogen.

11. The method of claim 9, further comprising introducing a second gas into said reactor chamber after said step of introducing oxygen.

12. The method of claim 11, wherein said second gas is selected from the group consisting of helium, argon and nitrogen.

13. A method of forming a rhodium upper electrode of a capacitor in an insulating layer of a substrate, comprising the steps of:

forming a conductive layer;

forming a dielectric layer over said conductive layer; and

forming a rhodium layer by atomic layer deposition at a temperature of about 100°

C. to about 200°

C. in contact with said dielectric layer, wherein said step of forming said rhodium layer further comprises the steps of introducing said substrate in a deposition region of a reactor chamber, forming a rhodium monolayer and introducing oxygen into said deposition chamber.

14. The method of claim 13, wherein said step of forming said rhodium layer by atomic layer deposition comprises introducing dicarbonyl cyclopentadienyl rhodium into said reactor chamber.

15. The method of claim 14, wherein said dicarbonyl cyclopentadienyl rhodium is introduced at a rate of about 0.1 sccm to about 500 sccm.

16. The method of claim 14, wherein said dicarbonyl cyclopentadienyl rhodium is introduced into said reactor chamber at a rate of about 0.1 sccm to about 5 sccm.

17. A method of forming a rhodium upper electrode of a capacitor in an insulating layer of a substrate, comprising the steps of:

forming a conductive layer;

forming a dielectric layer over said conductive layer; and

forming a rhodium layer by atomic layer deposition at a temperature of about 100°

C. to about 200°

C. over said dielectric layer, wherein said step of forming said rhodium layer by atomic layer deposition further comprises the steps of;

introducing said substrate in a deposition region of a reactor chamber;

introducing dicarbonyl cyclopentadienyl rhodium into said reactor chamber; and

introducing oxygen into said reactor chamber.

18. The method of claim 17, wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 500 sccm.

19. The method of claim 17, wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 200 sccm.

20. A method of forming a capacitor comprising the steps of:

forming a rhodium layer by atomic layer deposition at a temperature of about 100°

C. to about 200°

C., wherein said step of forming said rhodium layer by atomic layer deposition comprises;

introducing a substrate in a deposition region of a reactor chamber;

introducing dicarbonyl cyclopentadienyl rhodium into said reactor chamber;

introducing a gas selected from the group consisting of helium, argon and nitrogen; and

introducing oxygen to form said rhodium layer;

forming a dielectric layer over said rhodium layer; and

forming a conductive layer over said dielectric layer.

21. The method of claim 20, wherein said dicarbonyl cyclopentadienyl rhodium is introduced at a rate of about 0.1 sccm to about 500 sccm.

22. The method of claim 21, wherein said dicarbonyl cyclopentadienyl rhodium is introduced into said reactor chamber at rate of about 0.1 sccm to about 5 sccm.

23. A method of forming a capacitor comprising the steps of:

forming a rhodium layer by atomic layer deposition at a temperature of about 100°

C. to about 200°

C., wherein said step of forming said rhodium layer by atomic layer deposition further comprises introducing a substrate in a deposition region of a reactor chamber, introducing dicarbonyl cyclopentadienyl rhodium into said reactor chamber; and

introducing oxygen into said reactor chamber;

forming a dielectric layer over said rhodium layer; and

forming a conductive layer over said dielectric layer.

24. The method of claim 23, wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 500 sccm.

25. The method of claim 24, wherein said oxygen is introduced into said reactor chamber at a rate of about 10 to about 200 sccm.

26. A method of fabricating a DRAM cell container capacitor comprising the steps of:

forming a first and second conductive layer; and

forming a dielectric between said first and second conductive layer, at least one of said first and second conductive layer being a rhodium layer formed by atomic layer deposition of dicarbonyl cyclopentadienyl rhodium at a temperature of about 100°

C. to about 200°

C. and for about 5 seconds to form an organo-rhodium layer followed by exposure of said organo-rhodium layer to oxygen to form said rhodium layer.