Semiconductor device

• US 20010042920A1
• Filed: 01/12/2001
• Published: 11/22/2001
• Est. Priority Date: 01/14/2000
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Sahara, Massashi, Ohta, Hiroyuki, Nakajima, Takashi, Nishihara, Shinji, Iwasaki, Tomio, Miura, Hideo
• Granted Patent: US 6,476,492 B2
• Time in Patent Office: Days
• US Class Current: 257/758
• CPC Class Codes: H01L 23/53257 the principal metal being a refractory metal
• 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 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: H10B 12/09 with simultaneous manufacture of the peripheral circuit region and memory cells
• CPC Class Codes: H10B 12/315 with the capacitor higher than a bit line

Abstract

In a semiconductor device, which comprises a capacitor component comprising a first electrode, an oxide film with a high dielectric constant or ferroelectricity in contact with the first electrode and a second electrode in contact with the oxide film, as formed in this order, on one principal side of a silicon substrate with a metal wiring layer formed thereon, such problems as breaking of tungsten interconnect, lowering of reliability, lowering of yield, etc. of semi-conductor devices can be solved by using molybdenum-containing tungsten as the material of metal interconnect layer.

Claims

1. A semiconductor device, which comprises a semiconductor substrate;

a metal interconnect composed of tungsten as a main constituent material and containing molybdenum formed on one principal side of the semiconductor substrate; and

a capacitor component comprising a first electrode formed on the one principal side of the semiconductor substrate, an oxide film with a high dielectric constant or ferroelectricity formed in contact with the first electrode, and a second electrode formed in contact with the oxide film.

2. A semiconductor device according to

claim 1

, wherein the metal interconnect has a wiring width of 0.2 μ

m or less.

3. A semiconductor device according to

claim 1

, wherein the main constituent material of the oxide film is a material selected from the group consisting of tantalum oxide, barium strontium titanate (BST) and lead titanate zirconate (PZT).

4. A semiconductor device according to

claim 1

, wherein the content of molybdenum of the interconnect is 0.05 at. %-18 at. %.

5. A semiconductor device, which comprises a silicon substrate;

a metal interconnect with a line width of 0.2 μ

m or less composed of tungsten as a main constituent material and containing 0.05 at. %-18 at. % of molybdenum, formed on one principal side of the silicon substrate; and

a capacitor component comprising a first electrode formed on the one principal side of the silicon substrate, an oxide film selected from the group consisting of tantalum oxide, barium strontium titanate (BST) and lead titante zirconate (PZT), formed in contact with the first electrode and a second electrode formed in contact with the oxide film.

6. A semiconductor device, which comprises a semiconductor substrate with a metal interconnect layer formed thereon;

a memory LSI comprising a capacitor component comprising a first electrode, an oxide film with a high dielectric constant or ferroelectricity, formed in contact with the first electrode and a second electrode formed in contact with the oxide film; and

a logic LSI comprising a MOS transistor with a gate oxide film and a gate electrode formed thereon, the memory LSI and the logic LSI being mounted on one principal side of the semiconductor substrate, characterized in that the main constituent material of the metal interconnect layer is tungsten and the metal interconnect layer contains molybdenum.

7. A semiconductor device, which comprises a memory LSI comprising a first electrode, an oxide film with a high dielectric constant or ferroelectricity in contact with the first electrode and a second electrode in contact with the oxide film, as formed in this order, and a logic LSI comprising a MOS transistor with a gate oxide film and a gate electrode formed thereon, the memory LSI and the logic LSI being mounted on one principal side of a silicon substrate with a metal interconnect layer formed thereon, characterized in that the main constituent material of the oxide film is a material selected from the group consisting of tantalum oxide, barium strontium titanate (BST) and lead titanate zirconate (PZT), the line width of the metal interconnect layer is 0.2 μ

m or less, the main constituent material of the metal interconnect layer is tungsten and the metal interconnect layer contains 0.05 at. %-18 at. % of molybdenum.

8. A process for producing a semiconductor device, which comprises a step of providing a semiconductor substrate;

a step of forming a metal interconnect, composed of tungsten as the main constituent material and containing molybdenum on one principal side of the semiconductor substrate;

a step of forming a first electrode on the one principal side of the semiconductor substrate;

a step of forming an oxide film with a high dielectric constant or ferroelectricity so as to be in contact with the first electrode and then heating the oxide at a temperature of 600°

C. or higher; and

a step of forming a second electrode in contact with the oxide film.

9. A process for producing a semiconductor device, which comprises a step of providing a silicon substrate;

a step of forming a metal interconnect with a line width of 0.2 μ

m or less, composed of tungsten as the main constituent material and containing 0.05 at. %-18 at. % of molybdenum on one principal side of the silicon substrate;

a step of forming a first electrode on the one principal side of the silicon substrate;

a step of forming an oxide film selected from the group consisting of tantalum oxide, barium strontium titanate (BST) and lead titanate zirconate (PZT) in contact with the first electrode and then heating the oxide at a temperature of 700°

C. or higher; and

a step of forming a second electrode in contact with the oxide film after the completion of the heating step.