Low cost, high-density rectifier matrix memory

• US 7,933,133 B2
• Filed: 11/05/2008
• Issued: 04/26/2011
• Est. Priority Date: 11/05/2007
• Status: Expired due to Fees

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Contour Semiconductor, Inc.
• Inventors: Shepard, Daniel R., Langdo, Thomas A., Pitera, Arthur J.
• Primary Examiner(s): MAI, SON LUU
• Application Number:
  US12/265,456
• Publication Number:
  US 20090225579A1
• Time in Patent Office: 902 Days
• Field of Search: 365/51
• US Class Current: 365/51
• CPC Class Codes: G11C 13/00 Digital stores characterised by the use of storage elements not covered by groups G11C11/00, G11C23/00, or G11C25/00
• CPC Class Codes: G11C 13/0004 comprising amorphous/crystalline phase transition cells
• CPC Class Codes: G11C 17/06 using diode elements G11C17/14 takes precedence
• CPC Class Codes: G11C 17/16 using electrically-fusible links
• CPC Class Codes: G11C 2213/71 Three dimensional array
• CPC Class Codes: G11C 2213/72 Array wherein the access device being a diode
• CPC Class Codes: G11C 5/02 Disposition of storage elements, e.g. in the form of a matrix array
• CPC Class Codes: G11C 5/06 Arrangements for interconnecting storage elements electrically, e.g. by wiring
• CPC Class Codes: H01L 27/105 including field-effect components

Abstract

A high-density memory device is fabricated three-dimensionally in layers. To keep points of failure low, address decoding circuits are included within each layer so that, in addition to power and data lines, only the address signal lines need be interconnected between the layers.

Claims

1. An electronic memory device comprising a plurality of layers of circuitry, wherein:

a first layer comprises (i) storage circuitry for storing and facilitating retrieval of information and

(ii) decoding circuitry for selecting information in the storage circuitry; and

a substrate layer, disposed beneath the first layer, comprises a plurality of buffer drivers for receiving decoded signals from the decoding circuitry.

2. The electronic memory device of claim 1, wherein the first layer is connected to the substrate layer by conductive vias.

3. The electronic memory device of claim 1, wherein each of the plurality of buffer drivers comprises a transistor.

4. The electronic memory device of claim 3, wherein each of the plurality of buffer drivers consists essentially of a transistor.

5. The electronic memory device of claim 3, wherein each transistor is an NMOS transistor.

6. The electronic memory device of claim 3, wherein each transistor is a thin-film transistor.

7. The electronic memory device of claim 1, further comprising one or more additional layers.

8. The electronic memory device of claim 1, wherein the storage circuitry for storing and facilitating retrieval of information comprises:

a first plurality of generally parallel conductors;

a second plurality of generally parallel conductors overlapping and generally orthogonal to the first plurality of generally parallel conductors; and

a plurality of nonlinear conductive devices, each device located proximate to a point of overlap between the first and second pluralities of generally parallel conductors.

9. The electronic memory device of claim 8, wherein at least one of the plurality of nonlinear conductive devices is connected to the second plurality of generally parallel conductors proximate to the point of overlap between the first and second pluralities of generally parallel conductors.

11. The electronic memory device of claim 8, wherein the decoding circuitry comprises:

circuitry for causing a first voltage on a selected one of the first plurality of generally parallel conductors to differ from voltages on the others of the first plurality of generally parallel conductors; and

circuitry for causing a second voltage on a selected one of the second plurality of generally parallel conductors to differ from voltages on the others of the second plurality of generally parallel conductors,

wherein (i) the first and second voltages differ sufficiently to forward bias a nonlinear conductive device at the point of overlap between the selected one of the first plurality of generally parallel conductors and the selected one of the second plurality of generally parallel conductors, and (ii) a voltage differential between the non-selected ones of the first plurality of generally parallel conductors and the non-selected ones of the second plurality of generally parallel conductors is insufficient to forward bias a nonlinear conductive device at any point of overlap therebetween.

13. The electronic memory device of claim 1, wherein the storage circuitry comprises a programmable device.

14. The electronic memory device of claim 13, wherein the programmable device comprises a phase-change material.

15. The electronic memory device of claim 14, wherein the phase-change material comprises a chalcogenide alloy.

16. The electronic memory device of claim 1, wherein the storage circuitry comprises one of a fusible link and an antifusible link.

17. The electronic memory device of claim 8, wherein each of the plurality of nonlinear conductive devices comprises a programmable element.

10. An electronic memory device comprising a plurality of layers of circuitry, wherein:

a first layer comprises (i) storage circuitry for storing and facilitating retrieval of information comprising;

(a) a first plurality of generally parallel conductors;

(b) a second plurality of generally parallel conductors overlapping and generally orthogonal to the first plurality of generally parallel conductors; and

(c) a plurality of nonlinear conductive devices, each device connected to the first plurality of generally parallel conductors at approximately a point of overlap between the first and second pluralities of generally parallel conductors, and (ii) decoding circuitry for selecting information in the storage circuitry; and

a substrate layer, disposed beneath the first layer, comprises a plurality of buffer drivers for receiving decoded signals from the decoding circuitry,

wherein each of the plurality of nonlinear conductive devices comprises a fuse, an antifuse, or a phase-change material.

12. An electronic memory device comprising a plurality of layers of circuitry, wherein:

a first layer comprises (i) storage circuitry for storing and facilitating retrieval of information and (ii) decoding circuitry for selecting information in the storage circuitry; and

a substrate layer, disposed beneath the first layer, comprises a plurality of buffer drivers for receiving decoded signals from the decoding circuitry,

wherein the buffer drivers are connected between the circuitry for storing and facilitating retrieval of information and the decoding circuitry.