Memory device in a programmed state having a memory layer comprising conductive nanoparticles coated with an organic film formed between two conductive layers

• US 9,006,741 B2
• Filed: 01/23/2008
• Issued: 04/14/2015
• Est. Priority Date: 02/02/2007
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yoshizumi, Kensuke, Harima, Noriko
• Primary Examiner(s): MAI, ANH D
• Application Number:
  US12/018,339
• Publication Number:
  US 20080185578A1
• Time in Patent Office: 2,638 Days
• Field of Search: 257/50, 257/529, 257/530, 257/E23.147
• US Class Current: 257/50
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G11C 13/0014 comprising cells based on organic memory material
• CPC Class Codes: G11C 2213/79 Array wherein the access device being a transistor
• CPC Class Codes: H01L 23/5252 comprising anti-fuses, i.e. connections having their state changed from non-conductive to conductive
• 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 20/20 Programmable ROM [PROM] devices comprising field-effect components H10B20/10 takes precedence
• CPC Class Codes: H10B 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A memory device is provided, which includes a first conductive layer, a second conductive layer, and a memory layer interposed between the first conductive layer and the second conductive layer. The memory layer includes a first portion and a second portion, each of which includes at least a nanoparticle. The nanoparticle includes a conductive material coated with an organic film. The first portion is in contact with the first conductive layer and the second conductive layer, and a side surface of the first portion is surrounded by the second portion.

Claims

1. A memory device comprising:

a first conductive layer;

a second conductive layer;

a memory layer interposed between the first conductive layer and the second conductive layer, wherein;

the memory layer includes a first portion and a second portion,

wherein the second portion includes a composition and at least a nanoparticle including a first conductive material,

wherein the nanoparticle is coated with an organic thin film, and provided into the composition,

wherein the first portion comprises a second conductive material, the second conductive material is in electrical contact with the first conductive layer and the second conductive layer, and

wherein the first portion and the second portion are in contact with the first conductive layer and the second conductive layer,

a first partition wall and a second partition wall over the first conductive layer, the first partition wall and the second partition wall each having tapered shapes at its sides; and

an insulating layer over the second conductive layer, the first partition wall and the second partition wall,

wherein the memory layer is provided over the first conductive layer between the first partition wall and the second partition wall,

wherein a side surface of the memory layer and a side surface of the second conductive layer are in contact with the side with the tapered shape of the first partition wall or the second partition wall,

wherein a top of the first partition and a top of the second partition are over a top surface of the second conductive layer,

wherein the insulating layer is in contact with a whole top surface of the second conductive layer and is in contact with the top of the first partition wall and the top of the second partition wall, and

wherein the insulating layer is separated from the side surface of the second conductive layer by the first partition wall or the second partition wall.

2. The memory device according to claim 1, wherein a grain size of the nanoparticle is greater than or equal to 1 nm and less than or equal to 200 nm.

3. The memory device according to claim 1, wherein the organic thin film includes one of a surfactant, and a material forming a coordinate bond with the first conductive material.

4. The memory device according to claim 1, wherein the organic thin film includes a material selected from the group consisting of a surfactant, a material forming a coordinate bond with the first conductive material, a reducing agent, a binder, and a plasticizer.

5. The memory device according to claim 1, wherein the first portion is one of columnar and subulate in shape.

6. The memory device according to claim 1, wherein the first portion is not in contact with the second portion.

7. The memory device according to claim 1, further comprising an antenna over the memory layer, wherein the insulating layer is provided over and is in contact with the antenna.

8. The memory device according to claim 1, wherein the insulating layer is not in contact with the side surface of the memory layer.

9. The memory device according to claim 1, wherein the insulating layer is not in contact with the side surface of the second conductive layer.

10. The memory device according to claim 1,

wherein a surface of the first conductive layer which is in contact with the memory layer has a first wettability with respect to a fluid discharge material of the memory layer,

wherein surfaces of the first partition wall and the second partition wall which are not in contact with the first conductive layer have a second wettability with respect to a fluid discharge material of the memory layer, and

wherein the first wettability is higher than the second wettability.

11. A memory device comprising:

a first conductive layer;

a second conductive layer;

a memory layer interposed between the first conductive layer and the second conductive layer;

a transistor electrically connected to a memory element including the first conductive layer, the second conductive layer, and the memory layer, wherein;

the memory layer includes a first portion and a second portion,

wherein the second portion includes a composition and at least a nanoparticle including a first conductive material,

wherein the nanoparticle is coated with an organic thin film, and provided into the composition,

wherein the first portion comprises a second conductive material, the second conductive material is in electrical contact with the first conductive layer and the second conductive layer, and

wherein the first portion and the second portion are in contact with the first conductive layer and the second conductive layer,

a first partition wall and a second partition wall over the first conductive layer, the first partition wall and the second partition wall each having tapered shapes at its sides; and

an insulating layer over the second conductive layer, the first partition wall and the second partition wall,

wherein the memory layer is provided over the first conductive layer between the first partition wall and the second partition wall,

wherein a side surface of the memory layer and a side surface of the second conductive layer are in contact with the side with the tapered shape of the first partition wall or the second partition wall,

wherein a top of the first partition and a top of the second partition are over a top surface of the second conductive layer,

wherein the insulating layer is in contact with a whole top surface of the second conductive layer and is in contact with the top of the first partition wall and the top of the second partition wall, and

wherein the insulating layer is separated from the side surface of the second conductive layer by the first partition wall or the second partition wall.

12. The memory device according to claim 11, wherein a grain size of the nanoparticle is greater than or equal to 1 nm and less than or equal to 200 nm.

13. The memory device according to claim 11, wherein the organic thin film includes one of a surfactant, and a material forming a coordinate bond with the first conductive material.

14. The memory device according to claim 11, wherein the organic thin film includes a material selected from the group consisting of a surfactant, a material forming a coordinate bond with the first conductive material, a reducing agent, a binder, and a plasticizer.

15. The memory device according to claim 11, wherein the first portion is one of columnar and subulate in shape.

16. The memory device according to claim 11, wherein the first portion is not in contact with the second portion.

17. The memory device according to claim 11, further comprising an antenna over the memory layer, wherein the insulating layer is provided over and is in contact with the antenna.