Semiconductor integrated-circuit capacitor having a carbon film electrode

• US 5,440,157 A
• Filed: 07/16/1993
• Issued: 08/08/1995
• Est. Priority Date: 07/17/1992
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Aoyama, Tomonori, Imai, Keitaro, Okayama, Yasunori, Okano, Haruo
• Primary Examiner(s): Mintel, William
• Assistant Examiner(s): BROWN, PETER T
• Application Number:
  US08/094,422
• Time in Patent Office: 753 Days
• Field of Search: 257/77, 257/295, 257/310, 257/741, 257/750, 257/754, 257/296, 257/301, 257/306, 257/532, 257/535, 365/102
• US Class Current: 257/310
• CPC Class Codes: H01L 21/02263 deposition from the gas or vapour phase
• CPC Class Codes: H01L 21/31604 Deposition from a gas or vapour H01L21/31691, H01L21/31695 take precedence
• CPC Class Codes: H01L 28/55 with a dielectric comprising a perovskite structure material
• CPC Class Codes: H01L 28/56 the dielectric comprising two or more layers, e.g. comprising buffer layers, seed layers, gradient layers
• CPC Class Codes: H01L 28/60 Electrodes
• CPC Class Codes: H01L 29/49 Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET H01L29/435 takes precedence
• CPC Class Codes: H01L 29/92 Capacitors having potential barriers
• CPC Class Codes: H10B 12/033 the capacitor extending over the transistor

Abstract

A semiconductor integrated-circuit capacitor comprises a lower electrode formed on a semiconductor substrate, a capacitor insulating film formed on the lower electrode, and an upper electrode formed on the capacitor insulating film. The capacitor insulating film is made of a high-permittivity material, and at least one of the upper and lower electrodes is made of a carbon film or a multilayered film composed of a carbon film and a conductor film other than carbon.

Claims

1. A semiconductor integrated-circuit capacitor comprising a lower electrode formed on a semiconductor substrate, a capacitor insulating film formed on said lower electrode, and an upper electrode formed on said insulating film,

wherein said capacitor insulating film comprises a high-permittivity material, and only one of said upper electrode and said lower electrode comprises a carbon film.

2. A semiconductor integrated-circuit capacitor according to claim 1, wherein said high-permittivity material is selected form the group consisting of tantalum pentoxide, zirconium dioxide (ZrO₂), hafnium dioxide (HfO₂), niobium pentoxide (Nb₂ O₅), lead titanate (PbTiO₃), lead zirconate titanate (PZT), strontium titanate (SrTiO₃), and barium titanate (BaTiO₃).

3. A semiconductor integrated-circuit capacitor according to claim 1, wherein said high-permittivity material has a relative permittivity of 20 or more.

4. A semiconductor integrated-circuit capacitor according to claim 1, wherein said lower electrode consists essentially of a layer of impurity-doped silicon, and said upper electrode consists essentially of said carbon film.

5. A semiconductor integrated-circuit capacitor according to claim 1, wherein said lower electrode consists essentially of a layer of impurity-doped silicon, and said upper electrode consists essentially of a multilayered film composed of said carbon film and a conductor film other than carbon.

6. A semiconductor integrated-circuit capacitor according to claim 1, wherein said lower electrode consists essentially of a film of metal, and said upper electrode consists essentially of said carbon film.

7. A semiconductor integrated-circuit capacitor according to claim 1, wherein said lower electrode consists essentially of a film of metal, and said upper electrode consists essentially of a multilayered film composed of said carbon film and a conductor film other than carbon.

8. A semiconductor integrated-circuit capacitor comprising a lower electrode formed on a semiconductor substrate, a capacitor insulating film formed on said lower electrode, and an upper electrode formed on said insulating film,

wherein said capacitor insulating film comprises a high-permittivity material, and only one of said upper electrode and said lower electrode comprises a multilayered film composed of a carbon film and a conductor film other than carbon.

9. A semiconductor integrated-circuit capacitor according to claim 8, wherein said high-permittivity material is selected from the group consisting of tantalum pentoxide, zirconium dioxide (ZrO₂), hafnium dioxide (HfO₂), niobium pentoxide (Nb₂ O₅), lead titanate (PbTiO₃), lead zirconate titanate (PZT), strontium titanate (SrTiO₃), and barium titanate (BaTiO₃).

10. A semiconductor integrated-circuit capacitor according to claim 8, wherein said high-permittivity material has a relative permittivity of 20 or more.

11. A semiconductor integrated-circuit capacitor according to claim 8, wherein said lower electrode consists essentially of a layer of impurity-doped silicon, and said upper electrode consists essentially of a multilayered film composed of said carbon film and said conductor film other than carbon.

12. A semiconductor integrated-circuit capacitor according to claim 8, wherein said lower electrode consists essentially of a film of metal, and said upper electrode consists essentially of a multilayered film composed of said carbon film and said conductor film other than carbon.

13. A semiconductor integrated-circuit capacitor comprising a lower electrode formed on a semiconductor substrate, a capacitor insulating film formed on said lower electrode, and an upper electrode formed on said insulating film,

wherein said capacitor insulating film comprises silicon nitride, and only one of said upper electrode and said lower electrode consists essentially of a carbon film.

14. A semiconductor integrated-circuit capacitor comprising a lower electrode formed on a semiconductor substrate, a capacitor insulating film formed on said lower electrode, and an upper electrode formed on said insulating film,

wherein said capacitor insulating film comprises silicon nitride, and only one of said upper electrode and said lower electrode comprises a multilayered film composed of a carbon film and a conductor film other than carbon.