Magnetic tunnel junction device with diffusion barrier layer

• US 8,837,208 B2
• Filed: 12/12/2011
• Issued: 09/16/2014
• Est. Priority Date: 11/25/2009
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Li, Xia, Kang, Seung H., Zhu, Xiaochun
• Primary Examiner(s): Byrne, Harry W
• Assistant Examiner(s): REIDLINGER, RONALD LANCE
• Application Number:
  US13/323,212
• Publication Number:
  US 20120086089A1
• Time in Patent Office: 1,009 Days
• Field of Search: 365/158, 365/171, 365/173
• US Class Current: 365/158
• CPC Class Codes: G11C 11/15 using multiple magnetic layers G11C11/155 takes precedence
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: H01L 21/00 Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
• CPC Class Codes: H04W 52/12 Outer and inner loops
• CPC Class Codes: H04W 52/26 using transmission rate or quality of service QoS [Quality of Service]
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission
• CPC Class Codes: H04W 52/54 Signalisation aspects of the TPC commands, e.g. frame structure
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 72/566 of the information or information source or recipient
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: H04W 88/12 Access point controller devices
• CPC Class Codes: H10B 61/10 comprising components having two electrodes, e.g. diodes or MIM elements
• CPC Class Codes: H10N 50/01 Manufacture or treatment
• CPC Class Codes: H10N 50/10 Magnetoresistive devices

Abstract

A magnetic tunnel junction (MTJ) device and fabrication method is disclosed. A particular embodiment includes a magnetic tunnel junction structure above a bottom electrode. The particular embodiment further includes a portion of a diffusion barrier layer adjacent to the magnetic tunnel junction structure. A top of the magnetic tunnel junction structure is connected to a conductive layer.

Claims

1. An apparatus comprising:

a magnetic tunnel junction structure connected to an electrode;

a portion of a diffusion barrier layer connected to the magnetic tunnel junction structure;

a conductive layer, wherein the magnetic tunnel junction structure is connected to the conductive layer;

a cap layer further comprising;

a first portion adjacent to the diffusion barrier layer, wherein the cap layer and the diffusion barrier layer are distinct layers;

a second portion adjacent to the electrode; and

a third portion adjacent to the conductive layer; and

an insulating layer adjacent to the cap layer.

2. The apparatus of claim 1, wherein the electrode includes at least one of tantalum and tantalum nitride.

3. The apparatus of claim 1, wherein the diffusion barrier layer and the cap layer include different materials.

4. The apparatus of claim 3, wherein the diffusion barrier layer includes silicon nitride.

5. The apparatus of claim 1, wherein the insulating layer is adjacent to at least the second portion of the cap layer, and wherein the conductive layer comprises a second electrode.

6. The apparatus of claim 1, wherein the portion of the diffusion barrier layer is further in contact with the conductive layer.

7. The apparatus of claim 1, wherein a first width of the conductive layer is wider than a second width of the magnetic tunnel junction structure.

8. The apparatus of claim 1, wherein the conductive layer includes a first side in contact with the magnetic tunnel junction structure, and wherein the first side is in contact with the third portion.

9. The apparatus of claim 1, wherein the diffusion barrier layer is connected to the conductive layer, and wherein the diffusion barrier layer includes silicon carbide and the cap layer includes silicon nitride.

10. The apparatus of claim 1, further comprising a device selected from the group consisting of a set top box, a music player, a video player, an entertainment unit, a navigation device, a communications device, a personal digital assistant (PDA), a fixed location data unit, and a computer, into which the magnetic tunnel junction structure is integrated.

11. The apparatus of claim 1, wherein the apparatus is made according to a process, the process comprising:

forming the magnetic tunnel junction structure;

forming the diffusion barrier layer;

etching back the diffusion barrier layer, wherein etching back the diffusion barrier layer includes removing a second portion of the diffusion barrier layer, the second portion of the diffusion barrier layer connected to the magnetic tunnel junction structure;

forming the cap layer, wherein the cap layer is connected to the portion of the diffusion barrier layer;

forming an insulating layer that is adjacent to the cap layer; and

connecting the magnetic tunnel junction structure to the conductive layer.

12. The apparatus of claim 1, wherein the insulating layer is adjacent to the conductive layer.

13. The apparatus of claim 1, wherein the conductive layer is adjacent to a metal trench.

14. The apparatus of claim 1, further comprising:

a second magnetic tunnel junction connected to a second electrode; and

a second cap layer adjacent to electrode, the second cap layer adjacent to the second electrode, wherein the electrode and the second electrode are different electrodes.

15. The apparatus of claim 14, further comprising:

a metal trench, the metal trench adjacent to the second cap layer, the metal trench adjacent to the electrode; and

a via adjacent to the metal trench, wherein a second insulating layer is adjacent to the via, the metal trench, and the second cap layer.

16. The apparatus of claim 1, wherein the insulating layer is adjacent to the electrode.

17. The apparatus of claim 1, further comprising:

a second magnetic tunnel junction; and

a second cap layer, the second cap layer adjacent to the second magnetic tunnel junction, wherein the cap layer and the second cap layer are separated by the insulating layer.

18. An apparatus comprising:

an electrode;

means for representing a bit value based on a magnetization characteristic of at least one component of the means for representing the bit value;

a portion of a diffusion barrier layer connected to the means for representing the bit value;

a conductive layer connected to the means for representing the bit value;

a cap layer further comprising;

a first portion adjacent to the diffusion barrier layer, wherein the cap layer and the diffusion barrier layer are distinct layers;

a second portion adjacent to the electrode; and

a third portion adjacent to the conductive layer; and

an insulating layer adjacent to the cap layer.

19. The apparatus of claim 18, wherein the electrode includes at least one of tantalum and tantalum nitride.

20. The apparatus of claim 18, wherein the diffusion barrier layer includes at least one of silicon nitride or silicon carbide.

21. The apparatus of claim 18, further comprising a device selected from the group consisting of a set top box, a music player, a video player, an entertainment unit, a navigation device, a communications device, a personal digital assistant (PDA), a fixed location data unit, and a computer, into which the means for representing the bit value is integrated.

22. The apparatus of claim 18, wherein the apparatus is made according to a process, the process comprising:

forming the means for representing the bit value;

forming the diffusion barrier layer;

etching back the diffusion barrier layer, wherein etching back the diffusion barrier layer includes removing a second portion of the diffusion barrier layer, the second portion of the diffusion barrier layer connected to the means for representing the bit value;

forming the cap layer, wherein the cap layer is connected to the portion of the diffusion barrier layer;

forming an insulating layer adjacent to the cap layer; and

connecting the means for representing the bit value to the conductive layer.

23. A computer-readable non-transitory medium configured to store instructions executable by a processor, the computer-readable non-transitory medium comprising:

a magnetic tunnel junction structure connected to an electrode, wherein a magnetization characteristic associated with a layer of the magnetic tunnel junction structure indicates one of a plurality of bit values associated with the instructions;

a portion of a diffusion barrier layer connected to the magnetic tunnel junction structure;

a conductive layer, wherein the magnetic tunnel junction structure is connected to the conductive layer;

a cap layer comprising;

a first portion adjacent to the diffusion barrier layer, wherein the cap layer and the diffusion barrier layer are distinct layers;

a second portion adjacent to the electrode; and

a third portion adjacent to the conductive layer; and

an insulating layer adjacent to the cap layer.

24. A method comprising:

applying a voltage to at least a portion of a magnetic tunnel junction structure; and

in response to applying the voltage, determining a bit value associated with a magnetization characteristic of a layer of the magnetic tunnel junction structure,

wherein the magnetic tunnel junction structure is connected to an electrode, wherein a portion of a diffusion barrier layer is connected to the magnetic tunnel junction structure, wherein the magnetic tunnel junction structure is connected to a conductive layer, wherein a cap layer has at least a first portion adjacent to the portion of the diffusion barrier layer, wherein the cap layer and the diffusion barrier layer are distinct layers, wherein the cap layer further has at least a second portion adjacent to the electrode, wherein the cap layer further has at least a third portion adjacent to the conductive layer, and wherein the cap layer is adjacent to an insulating layer.