Cross point non-volatile memory cell

• US 8,605,486 B2
• Filed: 08/21/2012
• Issued: 12/10/2013
• Est. Priority Date: 04/03/2009
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk 3D LLC (Western Digital Corporation)
• Inventors: Scheuerlein, Roy E.
• Primary Examiner(s): King, Douglas
• Application Number:
  US13/591,097
• Publication Number:
  US 20130021837A1
• Time in Patent Office: 476 Days
• Field of Search: 365/158, 365/163, 365/171, 365/173
• US Class Current: 365/148
• CPC Class Codes: G11C 13/0007 comprising metal oxide memory material, e.g. perovskites
• CPC Class Codes: G11C 13/0069 Writing or programming circuits or methods
• CPC Class Codes: G11C 2013/0078 Write using current through the cell
• CPC Class Codes: G11C 2213/32 Material having simple binary metal oxide structure
• CPC Class Codes: G11C 2213/34 Material includes an oxide or a nitride
• CPC Class Codes: G11C 2213/71 Three dimensional array
• CPC Class Codes: G11C 2213/72 Array wherein the access device being a diode

Abstract

A memory system includes an X line, a first Y line, a second Y line, a semiconductor region of a first type running along the X line, first switching material and a first semiconductor region of a second type between the first Y line and the semiconductor region of the first type, second switching material and a second semiconductor region of the second type between the second Y line and the semiconductor region of the first type, and control circuitry. The control circuitry changes the programming state of the first switching material to a first state by causing a first current to flow from the second Y line to the first Y line through the first switching material, the second switching material, the semiconductor region of the first type, the first semiconductor region of the second type and the second semiconductor region of the second type.

Claims

1. A non-volatile storage apparatus, comprising:

an X line;

a first Y line;

a second Y line;

a semiconductor region of a first type running along the X line;

first switching material and a first semiconductor region of a second type between the first Y line and the semiconductor region of the first type, the first semiconductor region of the second type is adjacent to the semiconductor region of the first type;

second switching material and a second semiconductor region of the second type between the second Y line and the semiconductor region of the first type, the second semiconductor region of the second type is adjacent to the semiconductor region of the first type; and

control circuitry in communication with the X line and the first Y line and the second Y line, the control circuitry changes the programming state of the first switching material to a first state by causing a first current to flow from the second Y line to the first Y line through the first switching material and the second switching material.

2. The non-volatile storage apparatus of claim 1, wherein:

the control circuitry changes the programming state of the first switching material by causing the first current to flow from the second Y line to the first Y line through the first switching material, the second switching material and the semiconductor region of the first type.

3. The non-volatile storage apparatus of claim 1 wherein:

the first switching material and the second switching material are reversible resistance-switching material.

4. The non-volatile storage apparatus of claim 1, wherein:

the first switching material and the first semiconductor region of the second type form a pillar between the first Y line and the X line;

the second switching material and the second semiconductor region of the second type form a pillar between the second Y line and the X line;

the semiconductor region of the first type and the X line from a rail in one direction; and

the first Y line and the second Y line are rails in a direction different than the one direction.

5. The non-volatile storage apparatus of claim 1, wherein:

the control circuitry changes the programming state of the first switching material to a second state by causing a second current to flow from the first Y line to the X line through the first switching material and the semiconductor region of the first type.

6. The non-volatile storage apparatus of claim 1, wherein:

when changing the programming state of the first switching material to the first state, the control circuitry biases the X line to cause the semiconductor region of the first type, the first semiconductor region of the second type and the second semiconductor region of the second type to act like a transistor.

7. The non-volatile storage apparatus of claim 6, wherein:

the control circuitry changes the programming state of the first switching material by causing the first current to flow from the second Y line to the first Y line through the semiconductor region of the first type;

the first switching material and the second switching material are reversible resistance-switching material;

the first switching material and the first semiconductor region of the second type form a pillar between the first Y line and the X line;

the second switching material and the second semiconductor region of the second type form a pillar between the second Y line and the X line;

the semiconductor region of the first type and the X line from a rail in one direction; and

the first Y line and the second Y line are rails in a direction different than the one direction.

8. The non-volatile storage apparatus of claim 1, wherein:

the semiconductor region of the first type, the first switching material, the first semiconductor region of the second type, the second switching material and the second semiconductor region of the second type are part of a three dimensional monolithic memory array;

the X line is a word line; and

the first Y line and the second Y line are bit lines that are perpendicular to the X line.

9. A non-volatile storage apparatus, comprising:

a plurality of X line rails;

a plurality of Y line rails;

semiconductor regions of a first type shaped as rails and adjacent the X line rails;

pillars between the Y line rails and the X line rails, each of the pillars includes a resistive switching material and semiconductor region of a second type, the semiconductor region of the second type is positioned adjacent to the semiconductor regions of the first type that are shaped as rails, the pillars include a first pillar and a second pillar, the first pillar is positioned between a first Y line rail and a first X line rail, the second pillar is positioned between a second Y line rail and the first X line rail, the first pillar and the second pillar are adjacent a common semiconductor region of the first type; and

control circuitry in communication with the X line rails and the Y line rails, the control circuitry changes the programming state of the first pillar by causing a first current to flow from the second Y line rail to the first Y line rail through the common semiconductor region of the first type, the first pillar and the second pillar.

10. The non-volatile storage apparatus of claim 9, wherein:

when changing the programming state of the first pillar, the control circuitry biases the first X line rail to cause the common semiconductor region of the first type and semiconductor regions of the second type to act like a transistor.