Graphene-inserted phase change memory device and method of fabricating the same

Patent metadata

Field	Value
Publication number	US-9583702-B2
Application number	US-201615011199-A
Country	US
Kind code	B2
Filing date	Jan 29, 2016
Priority date	Mar 20, 2015
Publication date	Feb 28, 2017
Grant date	Feb 28, 2017

Abstract

Provided is a phase change memory device including a graphene layer inserted between a lower electrode into which heat flows and a phase change material layer, to prevent the heat from being diffused to an outside so as to efficiently transfer the heat to the phase change material layer, and a method of fabricating the phase change memory device. The phase change memory device includes a lower electrode; an insulating layer formed to enclose the lower electrode; a graphene layer formed on the lower electrode; a phase change material layer formed on the graphene layer and the insulating layer; and an upper electrode formed on the phase change material layer. Since a phase of the phase change material layer is changed at a small amount of driving current, the phase change memory device is fabricated to have a high driving speed and a high integration.

First claim

What is claimed is:

1. A phase change memory device comprising:
a lower electrode;
an insulating layer configured to enclose the lower electrode;
a graphene layer on the lower electrode;
a phase change material layer on the graphene layer and the insulating layer; and
an upper electrode on the phase change material layer.

2. The phase change memory device of claim 1 , wherein the graphene layer is only on the lower electrode and is not on the insulating layer.

3. The phase change memory device of claim 1 , wherein a width of the graphene layer is equal to a width of the lower electrode.

4. The phase change memory device of claim 1 , wherein the phase change material layer comprises a germanium antimony tellurium (GST) material.

5. A phase change memory device comprising:
a lower electrode;
an insulating layer configured to enclose the lower electrode;
a graphene layer on the lower electrode and the insulating layer;
a phase change material layer on the graphene layer; and
an upper electrode on the phase change material layer.

6. The phase change memory device of claim 5 , wherein the graphene layer covers the lower electrode and covers a part of the insulating layer.

7. The phase change memory device of claim 5 , wherein the graphene layer covers the lower electrode and an entirety of the insulating layer.

8. The phase change memory device of claim 5 , wherein the phase change material layer comprises a GST material.

9. A method of fabricating a phase change memory device, the method comprising:
sequentially forming an electrode layer and an insulating layer on a substrate;
removing a part of the insulating layer to expose the electrode layer;
forming a lower electrode in the removed part of the insulating layer and then planarizing an uppermost layer of the lower electrode and the insulating layer;
forming a graphene layer on the lower electrode and the insulating layer;
removing the graphene layer on the insulating layer; and
sequentially forming a phase change material layer and an upper electrode on the graphene layer and the insulating layer.

10. The method of claim 9 , wherein the graphene layer is formed by using a transfer method or a direct growth method.

11. The method of claim 9 , wherein the electrode layer and the lower electrode are formed of a same material.

12. The method of claim 9 , wherein all of the graphene layer formed on the insulating layer is removed.

13. The method of claim 9 , wherein a part of the graphene layer formed on the insulating layer is removed.

14. A method of fabricating a phase change memory device, the method comprising:
sequentially forming an electrode layer and an insulating layer on a substrate;
removing a part of the insulating layer to expose the electrode layer;
forming a lower electrode in the removed part of the insulating layer and then planarizing an uppermost layer of the lower electrode and the insulating layer;
forming a graphene layer on the lower electrode and the insulating layer; and
sequentially forming a phase change material layer and an upper electrode on the graphene layer.

15. The method of claim 14 , wherein the graphene layer is formed by using a transfer method or a direct growth method.

16. The method of claim 14 , wherein the electrode layer and the lower electrode are formed of a same material.

17. The method of claim 14 , wherein the graphene layer is formed to cover all of the lower electrode and the insulating layer.

Assignees

• Samsung Electronics Co Ltd
• Univ Leland Stanford Junior

Inventors

• Kim Yongsung
• Ahn Chiyui
• Sood Aditya
• Pop Eric
• Wong H -S Philip
• Goodson Kenneth E
• Fong Scott
• Lee Seunghyun
• Neumann Christopher M
• Asheghi Mehdi

Classifications

• H01L45/126

  Electricity · mapped topic

• H01L45/06

  Electricity · mapped topic

• H01L45/128 Primary

  Electricity · mapped topic

• H01L45/16

  Electricity · mapped topic

• H01L45/144

  Electricity · mapped topic