Method for forming a metal oxide film

• US 20040192036A1
• Filed: 03/24/2004
• Published: 09/30/2004
• Est. Priority Date: 03/27/2003
• Status: Active Grant

• Current Assignee: Longitude Licensing Limited (Vector Capital Corporation)
• Original Assignee: Elpida Memory Incorporated (Micron Technology, Inc.)
• Inventors: Koyanagi, Kenichi, Sakuma, Hiroshi
• Granted Patent: US 7,256,144 B2
• Time in Patent Office: Days
• US Class Current: 438/680
• CPC Class Codes: C23C 16/405 of refractory metals or yttrium
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: H01L 21/02175 characterised by the metal H01L21/02197 takes precedence
• 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 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/3141 Deposition using atomic layer deposition techniques [ALD]
• CPC Class Codes: H01L 21/31637 Deposition of Tantalum oxides, e.g. Ta2O5
• CPC Class Codes: H01L 28/84 being a rough surface, e.g. using hemispherical grains
• CPC Class Codes: H01L 28/90 having vertical extensions
• CPC Class Codes: H10B 12/033 the capacitor extending over the transistor

Abstract

A method for forming a capacitor insulation film includes the step of depositing a monoatomic film made of a metal by supplying a metal source including the metal and no oxygen, and depositing a metal oxide film including the metal by using a CVD technique. The method provides the metal oxide film having higher film properties with a higher throughput.

Claims

1. A method for forming a semiconductor device comprising the steps of:

depositing a monoatomic film including a metal on a base by using a metal source including a compound containing said metal and no oxygen;

depositing a metal oxide film including oxide of said metal on said monoatomic film by using a CVD technique.

2. The method according to claim 1, further comprising, before said monoatomic film depositing step, the step of supplying oxidizing gas onto a surface of said base.

3. The method according to claim 2, wherein said oxidizing gas includes heated H₂O.

4. The method according to claim 2, wherein said oxidizing gas includes at least one gas selected from the group consisting of O₂, active oxygen, ozone, and N₂O.

5. The method according to claim 1, further comprising, before said monoatomic film depositing step, the step of supplying hydrofluoric acid onto a surface of said base.

6. The method according to claim 1, wherein said metal source includes at least one said compound selected from the group consisting of TaCl₅, TaF₅, and Ta(N(C₂H₅)₂)₃, and said metal oxide film is tantalum oxide.

7. The method according to claim 1, wherein said metal source includes Al(CH₃)₃, and said metal oxide is titanium oxide.

8. The method according to claim 1, wherein said metal source includes TiCl₄ or Ti(N(CH₃)₂)₄ and said metal oxide is titanium oxide.

9. The method according to claim 1, wherein said metal source includes at least one said compound selected from the group consisting of Hf(NCH₃)₂)₄, Hf(N(C₂H₅)(CH₃))₄ and Hf(C₂H₅)₂)₄, and said metal oxide is hafnium oxide.

10. The method according to claim 1, wherein said metal source includes at least one said compound selected from the group consisting of NbCl₅, NbF₅ and Nb(N(C₂H₅)₂)₃, and said metal oxide is niobium oxide.

11. The method according to claim 1, further comprising, between said monoatomic film depositing step and said metal oxide film depositing step, the step of supplying oxidizing gas onto a surface of said monoatomic film.

13. The method according to claim 1, further comprising the step of forming a conductive film on said metal oxide film, wherein said steps are used for forming a capacitor including said base as a bottom electrode, said metal oxide film as a capacitor insulation film, and said conductive film as a top electrode.

12. The method according to claim 12, wherein said base is either silicon substrate, polysilicon film, silicon nitride film or a metallic film.