Semiconductor storage device and manufacturing method thereof

• US 20070075357A1
• Filed: 02/01/2006
• Published: 04/05/2007
• Est. Priority Date: 09/30/2005
• Status: Abandoned Application

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Tanaka, Masayuki, Ishida, Hirokazu
• Application Number:
  US11/344,074
• Publication Number:
  US 20070075357A1
• Time in Patent Office: Days
• US Class Current: 257/321
• CPC Class Codes: H10B 41/30 characterised by the memory core region
• CPC Class Codes: H10B 69/00 Erasable-and-programmable ROM [EPROM] devices not provided for in groups H10B41/00 - H10B63/00, e.g. ultraviolet erasable-and-programmable ROM [UVEPROM] devices

Abstract

A non-volatile semiconductor storage device having a high-dielectric-constant insulator and a manufacturing method thereof suitable for miniaturization are disclosed. According to one aspect of the present invention, it is provided a semiconductor storage device comprising a semiconductor substrate, a plurality of first conductor layers formed on the semiconductor substrate through a first insulator, an isolation formed between the plurality of first conductor layers, a silicon oxide film formed on the first conductor layer, a high-dielectric-constant insulator formed on the silicon oxide film and the isolation and being diffused silicon and oxygen at least in a surface thereof contacting with the silicon oxide film, and a second conductor film formed above the high-dielectric-constant insulator.

Claims

1. A semiconductor storage device comprising:

a semiconductor substrate;

a plurality of first conductor layers formed on the semiconductor substrate through a first insulator;

an isolation formed between the plurality of first conductor layers;

a silicon oxide film formed on the first conductor layer;

a high-dielectric-constant insulator formed on the silicon oxide film and the isolation and being diffused silicon and oxygen at least in a surface thereof contacting with the silicon oxide film; and

a second conductor film formed above the high-dielectric-constant insulator.

2. The semiconductor storage device according to claim 1, wherein the silicon oxide film has a film thickness of 4 nm or less.

3. The semiconductor storage device according to claim 1, wherein a relative dielectric constant of the second insulator is 5 or greater.

4. The semiconductor storage device according to claim 3, wherein the second insulator is a laminated film consisting of a plurality of insulators including an insulator whose relative dielectric constant is 5 or greater.

5. The semiconductor storage device according to claim 1, wherein the second insulator contains at least aluminum or hafnium.

6. The semiconductor storage device according to claim 1, wherein the second insulator contains at least an oxide or a nitride of aluminum, hafnium or zirconium.

7. A manufacturing method of a semiconductor storage device, comprising:

depositing a first conductor layer on a semiconductor substrate through a first insulator;

patterning the first conductor layer, the first insulator and the semiconductor substrate to form an isolation extending in a first direction;

forming a silicon oxide film on the first conductor layer;

depositing a high-dielectric-constant insulator on the silicon oxide film;

depositing a second conductor film on the high-dielectric-constant insulator;

recovering defects in the high-dielectric-constant insulator by decomposing the silicon oxide film and supplying oxygen and/or silicon to the insulator by a heat treatment; and

patterning the second conductor layer and the high-dielectric-constant insulator to be extended in a second direction orthogonal to the first direction to form a memory cell.

8. The manufacturing method of a semiconductor storage device according to claim 7, wherein the silicon oxide film has a film thickness of 1.5 nm to 4 nm.

9. The manufacturing method of a semiconductor storage device according to claim 7, wherein a relative dielectric constant of the second insulator is 5 or greater.

10. The manufacturing method of a semiconductor storage device according to claim 9, wherein the second insulator is a laminated film consisting of a plurality of insulators including an insulator whose relative dielectric constant is 5 or greater.

11. The manufacturing method of a semiconductor storage device according to claim 7, wherein the heat treatment for the recovering is performed at a temperature of 500°

C. to 1200°

C.

12. The manufacturing method of a semiconductor storage device according to claim 7, wherein the recovering is carried out between the depositing the high-dielectric-constant insulator and the depositing the second conductor layer.

13. The manufacturing method of a semiconductor storage device according to claim 7, wherein the silicon oxide film is completely decomposed during the recovering.

14. The manufacturing method of a semiconductor storage device according to claim 13, wherein the silicon oxide film has a film thickness of 1.5 nm to 4 nm.

15. The manufacturing method of a semiconductor storage device according to claim 13, wherein a relative dielectric constant of the second insulator is 5 or greater.

16. The manufacturing method of a semiconductor storage device according to claim 15, wherein the second insulator is a laminated film consisting of a plurality of insulators including an insulator whose relative dielectric constant is 5 or greater.

17. The manufacturing method of a semiconductor storage device according to claim 13, wherein the second insulator contains at least aluminum or hafnium.

18. The manufacturing method of a semiconductor storage device according to claim 17, wherein the second insulator contains at least an oxide or a nitride of aluminum, hafnium or zirconium.

19. The manufacturing method of a semiconductor storage device according to claim 13, wherein the heat treatment for the recovering is performed at a temperature of 500°

C. to 1200°

C.

20. The manufacturing method of a semiconductor storage device according to claim 13, wherein the recovering is carried out between the depositing the high-dielectric-constant insulator and the depositing the second conductor layer.