Semiconductor device and method having capacitor and capacitor insulating film that includes preset metal element

• US 7,485,915 B2
• Filed: 05/05/2006
• Issued: 02/03/2009
• Est. Priority Date: 06/30/2005
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nasu, Hayato, Usui, Takamasa, Shibata, Hideki
• Primary Examiner(s): Soward; Ida M
• Application Number:
  US11/418,467
• Publication Number:
  US 20070012973A1
• Time in Patent Office: 1,005 Days
• Field of Search: 257/68, 257/71, 257/277, 257296-300, 257306-313, 257/532, 257/535, 257/906, 257/908, 257/924, 257758-760
• US Class Current: 257/310
• CPC Class Codes: H01L 21/76831 in via holes or trenches, e.g. non-conductive sidewall liners
• CPC Class Codes: H01L 21/7687 Thin films associated with contacts of capacitors
• CPC Class Codes: H01L 23/5223 Capacitor integral with wiring layers
• CPC Class Codes: H01L 23/53233 Copper alloys
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 28/75 comprising two or more layers, e.g. comprising a barrier layer and a metal layer
• CPC Class Codes: H01L 28/91 made by depositing layers, e.g. by depositing alternating conductive and insulating layers
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y10S 257/906 Dram with capacitor electrodes used for accessing, e.g. bit line is capacitor plate
• CPC Class Codes: Y10S 257/908 Dram configuration with transistors and capacitors of pairs of cells along a straight line between adjacent bit lines
• CPC Class Codes: Y10S 257/924 with passive device, e.g. capacitor, or battery, as integral part of housing or housing element, e.g. cap

Abstract

A semiconductor device includes a capacitor which includes a capacitor insulating film at least including a first insulating film and a ferroelectric film formed in contact with the first insulating film, containing a compound of a preset metal element and a constituent element of the first insulating film as a main component and having a dielectric constant larger than that of the first insulating film, a first capacitor electrode formed of one of Cu and a material containing Cu as a main component, and a second capacitor electrode formed to sandwich the capacitor insulating film in cooperation with the first capacitor electrode.

Claims

1. A semiconductor device comprising:

a first capacitor which includes;

a first capacitor insulating film at least including a first insulating film and a first ferroelectric film formed in contact with the first insulating film, the first ferroelectric film containing a compound of a preset metal element and a constituent element of the first insulating film as a main component and having a dielectric constant larger than that of the first insulating film, and

first and second capacitor electrodes formed to sandwich the first capacitor insulating film and formed of one of Cu and a material containing Cu as a main component,

wherein the preset metal element contains at least one element selected from a group consisting of Mn, Nb, Zr, Cr, V, Y, Tc and Re, the constituent element contains O and at least one element selected from a group consisting of Si, C and F, and the first ferroelectric film contains a material selected from a group consisting of α

_xO_y, α

_x Si_yO_z, α

_xC_yO_z and α

_xF_yO_z as a main component, α

indicating the preset metal element.

2. The semiconductor device according to claim 1, wherein the first ferroelectric film is formed in contact with one of the first and second capacitor electrodes.

3. The semiconductor device according to claim 1, wherein the first capacitor insulating film further includes a second insulating film.

4. The semiconductor device according to claim 1, wherein the first capacitor insulating film further includes a second ferroelectric film which is formed in contact with the first insulating film in opposition to the first ferroelectric film, contains a compound of a preset metal element and a constituent element of the first insulating film as a main component and has a dielectric constant larger than that of the first insulating film.

5. The semiconductor device according to claim 1, wherein the first capacitor is formed along an inner wall of a trench formed in an inter-level insulating film.

6. The semiconductor device according to claim 1, further comprising a second capacitor formed on the first capacitor, wherein the second capacitor includes:

a second capacitor insulating film at least including a second insulating film and a second ferroelectric film formed in contact with the second insulating film, containing a compound of a preset metal element and a constituent element of the second insulating film as a main component and having a dielectric constant larger than that of the second insulating film, and

a third capacitor electrode formed to sandwich the second capacitor insulating film in cooperation with one of the first and second capacitor electrodes and formed of one of Cu and a material containing Cu as a main component.

7. The semiconductor device according to claim 1, further comprising:

an inter-level insulating film formed to cover the first capacitor,

a first contact interconnection formed in the inter-level insulating film, formed of one of Cu and a material containing Cu as a main component and electrically connected to the first capacitor electrode, and

a first barrier film formed on an interface between the inter-level insulating film and the first contact interconnection, containing a compound of a preset metal element and a constituent element of the inter-level insulating film as a main component and acting to prevent diffusion of Cu elements in the first contact interconnection.

8. The semiconductor device according to claim 7, further comprising:

a second contact interconnection formed in the inter-level insulating film, formed of one of Cu and a material containing Cu as a main component and electrically connected to the second capacitor electrode, and

a second barrier film formed on an interface between the inter-level insulating film and the second contact interconnection, containing a compound of a preset metal element and a constituent element of the inter-level insulating film as a main component and acting to prevent diffusion of Cu elements in the second contact interconnection.

9. The semiconductor device according to claim 8, wherein the preset metal element contains at least one element selected from a group consisting of Mn, Nb, Zr, Cr, V, Y, Tc and Re, the constituent element contains O and at least one element selected from a group consisting of Si, C and F, and the first and second barrier films and the first ferroelectric film each contain a material selected from a group consisting of α

_xO_y, α

_xSi_yO_z, α

_xC_yO_z and α

_xF_yO_z as a main component, a indicating the preset metal element.

10. A semiconductor device comprising:

a capacitor which includes;

a capacitor insulating film at least including a first insulating film and a ferroelectric film formed in contact with the first insulating film, containing a compound of a preset metal element and a constituent element of the first insulating film as a main component and having a dielectric constant larger than that of the first insulating film,

a first capacitor electrode formed of one of Cu and a material containing Cu as a main component, and

a second capacitor electrode formed to sandwich the capacitor insulating film in cooperation with the first capacitor electrode.

11. The semiconductor device according to claim 10, further comprising:

an inter level insulating film having a groove, the first capacitor electrode being embedded in the groove, and

a barrier film formed on an interface between the inter-level insulating film and the first capacitor electrode, containing a compound of the preset metal element and a constituent element of the inter-level insulating film as a main component and acting to prevent diffusion of Cu element in the first capacitor electrode.

12. The semiconductor device according to claim 11, wherein the ferroelectric film and the barrier film are formed integrally around the first capacitor electrode.

13. The semiconductor device according to claim 10, wherein the ferroelectric film and the first capacitor electrode are formed in contact with each other.

14. The semiconductor device according to claim 10, wherein the capacitor insulating film further includes a second insulating film.

15. The semiconductor device according to claim 10, wherein the first capacitor electrode are formed at the matrial containing Cu as a main component and the preset metal element.