Memory devices and formation methods

• US 8,455,853 B2
• Filed: 04/09/2012
• Issued: 06/04/2013
• Est. Priority Date: 10/30/2008
• Status: Active Grant

• Current Assignee: Ovonyx Memory Technology, LLC (Micron Technology, Inc.)
• Original Assignee: Micron Technology, Inc.
• Inventors: Liu, Jun, Sandhu, Gurtej S.
• Primary Examiner(s): WILCZEWSKI, MARY A
• Application Number:
  US13/442,047
• Publication Number:
  US 20120193598A1
• Time in Patent Office: 421 Days
• Field of Search: 257/2, 257/5, 257/379, 257/776, 257/E27.002, 257/E27.003, 257/E47.001, 257/4, 257/E45.002, 365/163, 438/455, 438/458
• US Class Current: 257/2
• CPC Class Codes: H01L 21/02225 characterised by the process for the formation of the insulating layer
• CPC Class Codes: H10B 63/20 comprising selection components having two electrodes, e.g. diodes
• CPC Class Codes: H10B 63/82 the switching components having a common active material layer
• CPC Class Codes: H10B 63/84 arranged in a direction perpendicular to the substrate, e.g. 3D cell arrays
• CPC Class Codes: H10N 70/011 Manufacture or treatment of multistable switching devices
• CPC Class Codes: H10N 70/231 based on solid-state phase change, e.g. between amorphous and crystalline phases, Ovshinsky effect
• CPC Class Codes: H10N 70/801 Constructional details of multistable switching devices
• CPC Class Codes: H10N 70/826 adapted for essentially vertical current flow, e.g. sandwich or pillar type devices
• CPC Class Codes: H10N 70/8828 Tellurides, e.g. GeSbTe

Abstract

A method includes forming an electrical insulator material over an integrated circuit having a metal-containing conductive interconnect and activating a dopant in a semiconductor material of a substrate to provide a doped region. The doped region provides a junction of opposite conductivity types. After activating the dopant, the substrate is bonded to the insulator material and at least some of the substrate is removed where bonded to the insulator material. After the removing, a memory cell is formed having a word line, an access diode, a state-changeable memory element containing chalcogenide phase change material, and a bit line all electrically connected in series, the access diode containing the junction as a p-n junction. A memory device includes an adhesion material over the insulator material and bonding the word line to the insulator material.

Claims

1. A memory device comprising:

an integrated circuit having

an electrical insulator material thereover;

a memory cell having a word line, an access diode above the word line, a state-changeable memory element above the access diode and containing chalcogenide phase change material, and a bit line above the memory element all electrically connected in series, the access diode containing a p-n junction in a semiconductor material, the bit line and the word line overlapping at a cross-point, and the access diode and memory element extending between the word line and the bit line at the cross-point; and

an electrically insulative adhesion material over the insulator material and bonding the word line to the insulator material.

2. The device of claim 1 wherein the integrated circuit comprises a structure selected from the group consisting of a memory array, a peripheral circuit, a central processing unit, an application-specific integrated circuit, a field-programmable gate array, and combinations thereof.

3. The device of claim 1 wherein the integrated circuit comprises a peripheral circuit configured to operate the memory cell formed thereover.

4. The device of claim 1 wherein the adhesion material comprises an organic nanoglue.

5. The device of claim 1 wherein the integrated circuit comprises another memory cell having another word line, another access diode, another state-changeable memory element containing chalcogenide phase change material, and another bit line all electrically connected in series, the other bit line and the other word line overlapping at another cross-point and the other access diode and other memory element extending between the other word line and the other bit line at the other cross-point.

6. The device of claim 1 wherein the insulator material is selected from the group consisting of silicon oxide, silicon nitride, silicon oxynitride, and combinations thereof.

7. The device of claim 1 wherein the interconnect exhibits properties such that, if exposed to at least one operating condition used in dopant activation, a physical structure of the interconnect would be altered.

8. The device of claim 7 wherein the at least one operating condition comprises heating to greater than 400°

C.

9. The device of claim 1 wherein the semiconductor material comprises a monocrystalline material and the p-n junction lies within the monocrystalline material.

10. The device of claim 1 wherein the semiconductor material comprises monocrystalline silicon exhibiting p-type conductivity.

11. A memory device comprising:

an integrated circuit having an electrical insulator material thereover;

a memory cell having a word line, an access diode above the word line, a state-changeable memory element above the access diode and containing chalcogenide phase change material, and a bit line above the memory element all electrically connected in series, the access diode containing a p-n junction in a semiconductor material, the bit line and the word line overlapping at a cross-point, and the access diode and memory element extending between the word line and the bit line at the cross-point; and

an electrically conductive adhesion material over the insulator material and bonding the word line to the insulator material.

12. The device of claim 11 wherein the integrated circuit comprises another memory cell having another word line, another access diode, another state-changeable memory element containing chalcogenide phase change material, and another bit line all electrically connected in series, the other bit line and the other word line overlapping at another cross-point and the other access diode and other memory element extending between the other word line and the other bit line at the other cross-point.

13. The device of claim 11 wherein the interconnect exhibits properties such that, if exposed to at least one operating condition used in dopant activation, a physical structure of the interconnect would be altered.

14. The device of claim 13 wherein the at least one operating condition comprises heating to greater than 400°

C.

15. A memory device comprising:

an integrated circuit having an electrical insulator material thereover; and

a memory cell having a word line, an access diode above the word line, a state-changeable memory element above the access diode and containing chalcogenide phase change material, and a bit line above the memory element all electrically connected in series, the access diode containing a p-n junction in a semiconductor material, the bit line and the word line overlapping at a cross-point, the access diode and memory element extending between the word line and the bit line at the cross-point, a via in series electrical connection with and between the access diode and the memory element, the via comprising a conductive liner and insulative fill material radially inward thereof; and

an adhesion material over the insulator material and bonding the word line to the insulator material.

16. The device of claim 15 wherein the conductive liner comprises TiN.

17. The device of claim 15 wherein the conductive liner does not comprise TiN.

18. The device of claim 15 wherein the conductive liner comprises a conductive material other than TiN.

19. The device of claim 18 wherein the conductive liner comprises TiN.

20. The device of claim 15 wherein the conductive liner comprises spaced vertically extending portions in at least one straight line cross section.

21. The device of claim 15 wherein the conductive liner comprises a horizontally extending portion in at least one straight line cross section.

22. The device of claim 15 wherein the conductive liner comprises spaced vertically extending portions in at least one straight line cross section and a horizontally extending portion in the straight line cross section connected with the spaced vertically extending portions.

23. The device of claim 15 wherein the conductive liner is generally U-shaped in at least one straight line cross section.

24. The device of claim 15 wherein the adhesion material is electrically conductive.

25. The device of claim 15 wherein the adhesion material is electrically insulative.