Method of Forming Metal Oxide Using an Atomic Layer Deposition Process

• US 20070292628A1
• Filed: 06/28/2007
• Published: 12/20/2007
• Est. Priority Date: 06/09/2004
• Status: Active Grant

• Current Assignee: Jung-Ho Lee, Jung-Sik Chol, Jun-Hyun Cho, Sang-Mun Chon
• Original Assignee: Jung-Ho Lee, Jung-Sik Chol, Jun-Hyun Cho, Sang-Mun Chon
• Inventors: Lee, Jung-Ho, Cho, Jun-Hyun, Chol, Jung-Sik, Chon, Sang-mun
• Granted Patent: US 7,605,094 B2
• Time in Patent Office: Days
• US Class Current: 427/453
• 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: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• CPC Class Codes: H01L 21/02186 the material containing titanium, e.g. TiO2
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• 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 21/31608 Deposition of SiO2 H01L21/31625, H01L21/31629 and H01L21/31633 take precedence
• CPC Class Codes: H01L 21/31616 Deposition of Al2O3
• 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

In a method of forming a metal oxide, an organic metal compound represented by the following chemical formula is introduced into a chamber to chemisorb the organic metal compound onto a substrate,
M[L1]x[L2]y
where M represents a metal, L1 and L2 respectively represents a first and second ligands. In addition, x and y are independently integers and a value of (x+y) is 3 to 5. An oxygen-containing compound is introduced into the chamber to form the metal oxide. The metal oxide is formed by reacting an oxygen of the oxygen-containing compound with the metal, and separating the ligand from the metal. Thus, the metal oxide having a superior step coverage and a high dielectric constant may be formed using the organic metal compound by an atomic layer deposition process.

Claims

1. A method of forming a metal oxide comprising:

introducing a first reactant including a metal, at least one amino group and at least one multidentate ligand including at least two electron pair donors into a chamber to chemisorb the first reactant onto a substrate, and to bond the amino group and the multidentate ligand to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the amino group and the multidentate ligand from the metal.

2. The method of claim 1, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal and R₁ to R₈ independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.

3. The method of claim 2, wherein —

N(R₁)(R₂) and —

N(R₃)(R₄) are substantially identical to each other.

4. The method of claim 2, wherein the first reactant includes at least one compound selected from the group consisting of Hf(NEt₂)₂(DMAMP)₂, Hf(NEtMe)₂(DMAMP)₂ and Ti(NEt₂)₂(DMAMP)₂.

5. The method of claim 1, wherein introducing the first reactant, removing the non-chemisorbed first reactant, and introducing the second reactant are performed at a temperature of about 200°

C. to about 400°

C.

6. The method of claim 1, wherein the first reactant has a temperature of about 40°

C. to about 100°

C. before introducing into the chamber.

7. The method of claim 1, wherein after introducing the second reactant into the chamber, further comprising removing an unreacted second reactant, the amino group and the multidentate ligand from the chamber, the multidentate ligand being separated from the metal by reacting the second reactant with the chemisorbed first reactant.

8. A method of forming a metal oxide comprising:

introducing a first reactant including a metal, at least one alkoxide group and at least one multidentate ligand including at least two electron pair donors into a chamber to chemisorb the first reactant onto a substrate, and to bond the alkoxide group and the multidentate ligand to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the alkoxide group and the multidentate ligand from the metal.

9. The method of claim 8, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal, and R₁ to R₆ independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.

10. The method of claim 9, wherein —

R₁O and —

R₂O are substantially identical to each other.

11. The method of claim 9, wherein the first reactant includes Ti(OtBu)₂ (DMAMP)₂.

12. The method of claim 8, wherein introducing the first reactant, removing the non-chemisorbed first reactant, and introducing the second reactant are performed at a temperature of about 200°

C. to about 400°

C.

13. The method of claim 12, wherein the first reactant has a temperature of about 40°

C. to about 100°

C. before introducing into the chamber.

14. The method of claim 12, wherein after introducing the second reactant into the chamber, further comprising removing an unreacted second reactant, the alkoxide group and the multidentate ligand from the chamber, the multidentate ligand being separated from the metal by reacting the second reactant with the chemisorbed first reactant.