Switching device with solid electrolyte layer

• US 7,935,949 B2
• Filed: 06/02/2009
• Issued: 05/03/2011
• Est. Priority Date: 12/29/2008
• Status: Expired due to Fees

• Current Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Original Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Inventors: Lee, Yu-Jin
• Primary Examiner(s): Smith; Bradley K
• Assistant Examiner(s): Valentine; Jami M
• Application Number:
  US12/476,330
• Publication Number:
  US 20100165543A1
• Time in Patent Office: 700 Days
• Field of Search: 257 1- 5, 257/E29.002, 438102-103, 365/163, 361/435
• US Class Current: 257/2
• CPC Class Codes: H10N 70/245 the species being metal cations, e.g. programmable metallization cells
• CPC Class Codes: H10N 70/826 adapted for essentially vertical current flow, e.g. sandwich or pillar type devices
• CPC Class Codes: H10N 70/8416 adapted for supplying ionic species
• CPC Class Codes: H10N 70/8822 Sulfides, e.g. CuS
• CPC Class Codes: H10N 70/8825 Selenides, e.g. GeSe
• CPC Class Codes: H10N 70/8833 Binary metal oxides, e.g. TaOx

Abstract

A switching device with a solid electrolyte layer includes: a substrate; a lower electrode formed over the substrate; a solid electrolyte layer disposed over the lower electrode; and an upper electrode formed over the solid electrolyte layer.

Claims

1. A switching device with a solid electrolyte layer, comprising:

a substrate;

a lower electrode formed over the substrate;

a solid electrolyte layer disposed over the lower electrode; and

an upper electrode formed over the solid electrolyte layer,

wherein the solid electrolyte layer is formed of Gd_xS_y, where Gd denotes gadolinium, S denotes sulfide, and x and y denote positive numbers.

2. The switching device of claim 1, wherein the upper electrode includes diffusive metal.

3. The switching device of claim 2, wherein the diffusive metal is any one selected from the group consisting of copper (Cu), silver (Ag), and zinc (Zn).

4. The switching device of claim 2, wherein the solid electrolyte layer is doped with a metal which is the same as the diffusive metal.

5. The switching device of claim 1, wherein the switching device is switched between an on state and an off state, as a conductive path is created in or removed from the solid electrolyte layer according to voltages applied to the lower electrode and the upper electrode.

6. The switching device of claim 1, wherein the switching device forms a memory cell.

7. A switching device, comprising:

a substrate;

a lower electrode formed over the substrate;

a first solid electrolyte layer disposed over the lower electrode;

a second solid electrolyte layer disposed over the first solid electrolyte layer; and

an upper electrode formed over the second solid electrolyte layer.

8. The switching device of claim 7, wherein the second solid electrolyte layer is formed thicker than the first solid electrolyte layer.

9. The switching device of claim 7, wherein the first solid electrolyte layer has a thickness equal to or less than approximately 10 nm.

10. The switching device of claim 7, wherein the first solid electrolyte layer is formed of Gd_xO_y, where Gd denotes gadolinium, O denotes oxygen;

and x and y denote positive numbers.

11. The switching device of claim 7, wherein the second solid electrolyte layer is formed of Gd_aS_b, where Gd denotes gadolinium, S denotes sulfide, and a and b denote positive numbers.

12. The switching device of claim 7, wherein the upper electrode includes diffusive metal.

13. The switching device of claim 12, wherein the diffusive metal is any one selected from the group consisting of copper (Cu), silver (Ag), and zinc (Zn).

14. The switching device of claim 12, wherein the second solid electrolyte layer is doped with a metal that is the same as the diffusive metal.

15. The switching device of claim 7, wherein the switching device is switched between an on state and an off state, as a conductive path is created in or removed from the first solid electrolyte layer and the second solid electrolyte layer according to voltages applied to the lower electrode and the upper electrode.

16. The switching device of claim 7, wherein the switching device forms a memory cell.