U.S. patent application number 14/083845 was filed with the patent office on 2014-12-25 for near-field transducer peg encapsulation.
This patent application is currently assigned to Seagate Technology LLC. The applicant listed for this patent is Seagate Technology LLC. Invention is credited to Sarbeswar Sahoo, James Gary Wessel.
Application Number | 20140376341 14/083845 |
Document ID | / |
Family ID | 52110827 |
Filed Date | 2014-12-25 |
United States Patent
Application |
20140376341 |
Kind Code |
A1 |
Wessel; James Gary ; et
al. |
December 25, 2014 |
NEAR-FIELD TRANSDUCER PEG ENCAPSULATION
Abstract
A near field transducer with a peg region, an enlarged region
disposed adjacent the peg region, and a barrier material disposed
between the peg region and the enlarged region. The barrier
material reduces or eliminates interdiffusion of material between
the peg region and the enlarged region.
Inventors: |
Wessel; James Gary; (Savage,
MN) ; Sahoo; Sarbeswar; (Shakopee, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Seagate Technology LLC |
Cupertino |
CA |
US |
|
|
Assignee: |
Seagate Technology LLC
Cupertino
CA
|
Family ID: |
52110827 |
Appl. No.: |
14/083845 |
Filed: |
November 19, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61838862 |
Jun 24, 2013 |
|
|
|
Current U.S.
Class: |
369/13.33 ;
29/603.07 |
Current CPC
Class: |
G11B 5/1278 20130101;
G11B 5/3133 20130101; G11B 5/4866 20130101; G11B 13/08 20130101;
G11B 5/1871 20130101; G11B 5/187 20130101; Y10T 29/49025 20150115;
Y10T 29/49032 20150115; G11B 5/314 20130101; G11B 5/6088 20130101;
G11B 2005/0021 20130101; G11B 5/127 20130101; G11B 5/3163
20130101 |
Class at
Publication: |
369/13.33 ;
29/603.07 |
International
Class: |
G11B 13/08 20060101
G11B013/08; G11B 5/31 20060101 G11B005/31 |
Claims
1. An apparatus, comprising: a near field transducer comprising a
peg region and an enlarged region disposed adjacent the peg region;
and a barrier material disposed between the peg region and the
enlarged region configured to reduce interdiffusion between the peg
region and the enlarged region.
2. The apparatus of claim 1, wherein the peg region comprises a
plasmonic metal.
3. The apparatus of claim 2, wherein the enlarged region comprises
a second plasmonic metal that has a same composition as the
plasmonic metal of the peg region.
4. The apparatus of claim 1, wherein the barrier material comprises
one or more of ZrN, ZrN, TiN, Rh, Zr, Hf, Ru, AuN, TaN, Ir, W, Mo,
Co, and alloys thereof.
5. The apparatus of claim 1, wherein the barrier material comprises
one or more layers that substantially separate the peg region from
the enlarged region.
6. The apparatus claim 1, wherein the barrier material extends
along a non-media interfacing end of the peg region.
7. The apparatus of claim 1, wherein the barrier material has a
thickness of between about 1.0 nm and about 10.0 nm.
8. The apparatus of claim 1, wherein the barrier material is
disposed only between the enlarged region and the peg region.
9. The apparatus of claim 1, wherein the barrier material is
disposed between the enlarged region and the peg region and along
one or more additional surfaces of the enlarged region.
10. The apparatus of claim 1, wherein the enlarged region is a disk
shaped object.
11. An apparatus, comprising: a system configured to facilitate
heat assisted magnetic recording; and a near field transducer
disposed in the system, the near field transducer comprising: a peg
region and an enlarged region; and a barrier material disposed
between the peg region and the enlarged region configured to reduce
interdiffusion between the peg region and the enlarged region.
12. The system of claim 11, wherein the enlarged region comprises a
second plasmonic material that has a same composition as a first
plasmonic material of the peg region.
13. The system of claim 11, wherein the barrier material comprises
one or more of ZrN, TiN, Rh, Zr, Hf, Ru, AuN, TaN, Ir, W, Mo, Co,
and alloys thereof.
14. The system of claim 11, wherein the barrier material has a
thickness of between about 1.0 nm and about 10.0 nm.
15. The system of claim 11, wherein the barrier material is
disposed only between the enlarged region and the peg region.
16. The system of claim 11, wherein the barrier material is
disposed between the enlarged region and the peg region and along
one or more additional surfaces of the enlarged region.
17. A method, comprising: forming a peg region of a near field
transducer along a substrate of a heat assisted magnetic recording
head; disposing a sacrificial material over a first portion of the
peg region leaving a second portion of the peg region exposed;
fabricating a barrier material over at least the second portion of
the peg region; forming an enlarged region adjacent the second
portion of the peg region such that the barrier material is
disposed at least between the second portion and the enlarged
region to reduce interdiffusion between the peg region and the
enlarged region; and removing the sacrificial material.
18. The method of claim 17, wherein the step of fabricating
includes annealing the second portion.
19. The method of claim 18, wherein the step of annealing comprises
contacting the second portion with one or more of nitrogen,
nitrogen plasma, oxygen, and oxygen plasma.
20. The method of claim 17, wherein the step of fabricating the
barrier material comprises electroplating one or more surfaces of
the second portion.
Description
SUMMARY
[0001] Embodiments disclosed include a near field transducer with a
peg region, an enlarged region disposed adjacent the peg region,
and a barrier material disposed between the peg region and the
enlarged region. The barrier material reduces or eliminates
interdiffusion of material between the peg region and the enlarged
region.
[0002] Embodiments are directed to a system for a heat assisted
magnetic recording head that includes a near field transducer
having a peg region, an enlarged region, and a barrier material.
The barrier material is disposed between the peg region and the
enlarged region to reduce interdiffusion of material between the
peg region and the enlarged region.
[0003] Further embodiments are directed to a method of fabricating
a near field transducer for a heat assisted magnetic recording head
including forming a peg region along a substrate of a heat assisted
magnetic recording head, disposing a sacrificial material over a
first portion of the peg region leaving a second portion of the peg
region exposed, fabricating a barrier material over at least the
second portion of the peg region, forming an enlarged region
adjacent the second portion of the peg region such that the barrier
material is disposed at least between the second portion and the
enlarged region to reduce interdiffusion between the peg region and
the enlarged region, and removing the sacrificial material.
[0004] The above summary is not intended to describe each disclosed
embodiment or every implementation of the present disclosure. The
figures and the detailed description below more particularly
exemplify illustrative embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Throughout the specification reference is made to the
appended drawings, where like reference numerals designate like
elements, and wherein:
[0006] FIG. 1 is a perspective view of a hard drive slider that
includes a disclosed near-field transducer;
[0007] FIG. 2 is a side cross-sectional view of an apparatus that
includes the near-field transducer of FIG. 1, a write pole, a heat
sink, and a waveguide according to an example embodiment;
[0008] FIG. 3 is a first cross-sectional view of one embodiment of
a near-field transducer that includes a peg region separated from
an enlarged region by a barrier material;
[0009] FIG. 3A is a second cross-sectional view of the near-field
transducer of FIG. 3;
[0010] FIG. 4 is side cross-sectional view of another embodiment of
a near-field transducer that includes a peg region separated from
an enlarged region by a barrier material;
[0011] FIG. 4A is a second cross-sectional view of the near-field
transducer of FIG. 4;
[0012] FIG. 5 is a cross-sectional view of another embodiment of a
near-field transducer with a spacing element and a peg region of
the near-field transducer separated from one another;
[0013] FIG. 5A is a second cross-sectional view of the near-field
transducer and spacing element of FIG. 5; and
[0014] FIG. 6 is an illustration of one step in various fabrication
techniques used to form a near-field transducer.
[0015] The figures are not necessarily to scale. Like numbers used
in the figures refer to like components. However, it will be
understood that the use of a number to refer to a component in a
given figure is not intended to limit the component in another
figure labeled with the same number.
DETAILED DESCRIPTION
[0016] In the following description, reference is made to the
accompanying set of drawings that form a part of the description
hereof and in which are shown by way of illustration several
specific embodiments. It is to be understood that other embodiments
are contemplated and may be made without departing from the scope
of the present disclosure. The following detailed description,
therefore, is not to be taken in a limiting sense.
[0017] Unless otherwise indicated, all numbers expressing feature
sizes, amounts, and physical properties used in the specification
and claims are to be understood as being modified in all instances
by the term "about." Accordingly, unless indicated to the contrary,
the numerical parameters set forth in the foregoing specification
and attached claims are approximations that can vary depending upon
the desired properties sought to be obtained by those skilled in
the art utilizing the teachings disclosed herein. The use of
numerical ranges by endpoints includes all numbers within that
range (e.g. 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5) and
any range within that range.
[0018] Various embodiments disclosed herein are generally directed
to systems and apparatuses that facilitate coupling a laser diode
to a magnetic writer that includes a magnetic write head. In
particular, the systems and apparatuses include a plasmonic
near-field transducer for heat assisted magnetic recording (HAMR).
Plasmonic near-field transducers (NFTs) can generate a large amount
of heat in their writing tip also called a "peg" or "peg region".
This heat can negatively impact the operational life of the
near-field transducer. Disclosed are apparatuses, systems, and
methods directed to increasing NFT operational life by reducing
likelihood of peg recession of the writing tip. In particular,
disclosed herein are systems, apparatuses, and methods that
separate a peg region from the remainder of the NFT by a barrier
material. This encapsulation of the peg region (writing tip) from
the remainder of the NFT reduces or eliminates interdiffusion of
material between the peg region and the remainder of the NFT. The
reduction or elimination of interdiffusion of material reduces the
likelihood of peg recession. Thus, the near-field transducer can
better withstand heat buildup in the peg for HAMR.
[0019] The present disclosure relates to HAMR, which can be used to
increase areal data density of magnetic media. In a HAMR device,
information bits are recorded in a storage layer at elevated
temperatures in a specially configured magnetic media. The use of
heat can overcome superparamagnetic effects that might otherwise
limit the areal data density of the media. As such, HAMR devices
may include magnetic write heads for delivering electromagnetic
energy to heat a small confined media area (spot size) at the same
time the magnetic write head applies a magnetic field to the media
for recording.
[0020] One way to achieve a tiny confined hot spot is to use an
optical near-field transducer (NFT), such as a plasmonic optical
antenna or an aperture, located near an air-bearing surface of a
hard drive slider. Light may be launched from a light source (e.g.,
a laser diode) into optics such as a waveguide integrated into the
slider. Light propagating in the waveguide may be directed to an
optical focusing element, such as a planar solid immersion mirror
(PSIM). The PSIM may concentrate the energy into a NFT. The NFT
causes the energy to be delivered to the media in a very small
spot.
[0021] FIG. 1 is a perspective view of a hard drive slider that
includes a disclosed plasmonic NFT. HAMR slider 100 includes laser
diode 102 located on top of HAMR slider 100 proximate to trailing
edge surface 104 of HAMR slider 100. Laser diode 102 delivers light
proximate to read/write head 106, which has one edge on air-bearing
surface 108 (also referred to as "media-facing surface" or "media
interfacing surface") of HAMR slider 100. Air-bearing surface 108
is held proximate to a moving media surface (not shown) during
device operation.
[0022] Laser diode 102 provides electromagnetic energy to heat the
media at a point near to read/write head 106. Optical coupling
components, such as a waveguide 110, are formed integrally within
HAMR slider 100 to deliver light from laser diode 102 to the media.
In particular, waveguide 110 and NFT 112 may be located proximate
read/write head 106 to provide local heating of the media during
write operations. Laser diode 102 in this example may be an
integral, edge-emitting device, although it will be appreciated
that waveguide 110 and NFT 112 may be used with any light source
and light delivery mechanisms. For example, a surface emitting
laser (SEL) may be used instead of the edge firing laser
illustrated.
[0023] While the example in FIG. 1 shows laser diode 102 integrated
with HAMR slider 100, the NFT 112 discussed herein may be useful in
any type of light delivery configuration. For example, in a
free-space light delivery configuration, a laser may be mounted
externally to the slider, and coupled to the slider by way of optic
fibers and/or waveguides. The slider in such an arrangement may
include a grating coupler into which light is coupled and delivered
to slider-integrated waveguide 110 which energizes the NFT 112.
[0024] The HAMR device utilizes the types of optical devices
described above to heat he magnetic recording media (e.g., hard
disc) in order to overcome the superparamagnetic effects that limit
the areal data density of typical magnetic media. When writing to a
HAMR medium, the light can be concentrated into a small hotspot
over the track where writing takes place. The light propagates
through waveguide 110 where it is coupled to the NFT 112 either
directly from the waveguide or by way of a focusing element. Other
optical elements, such as couplers, mirrors, prisms, etc., may also
be formed integral to the slider. The optical elements used in HAMR
recording heads are generally referred to as integrated optics
devices.
[0025] As a result of what is known as the diffraction limit,
optical components cannot be used to focus light to a dimension
that is less than about half the wavelength of the light. The
lasers used in some HAMR designs produce light with wavelengths on
the order of 700-1550 nm, yet the desired hot spot is on the order
of 50 nm or less. Thus the desired hot spot size is well below half
the wavelength of the light. Optical focusers cannot be used to
obtain the desired hot spot size, being diffraction limited at this
scale. As a result, the NFT 112 is employed to create a hotspot on
the media.
[0026] The NFT 112 is a near-field optics device designed to reach
local surface plasmon resonance at a designed wavelength. A
waveguide and/or other optical element concentrates light on a
transducer region (e.g., focal point) where the NFT 112 is located.
The NFT 112 is designed to achieve surface plasmon resonance in
response to this concentration of light. At resonance, a high
electric field surrounds the NFT 112 due to the collective
oscillations of electrons at the metal surface. Part of this field
will tunnel into a storage medium and get absorbed, thereby raising
the temperature of a spot on the media as it being recorded. NFTs
generally have a surface that is made of a material that supports
surface plasmons ("plasmonic metal") such as aluminum, gold,
silver, copper, or alloys thereof. They may also have other
materials but they must have a material that supports surface
plasmons on their outer surface.
[0027] FIG. 2 is a cross-sectional view shows details of an
apparatus 200 used for HAMR according to an example embodiment. The
NFT 112 is located proximate a media interfacing surface 202 (e.g.,
ABS), which is held near a magnetic recording media 204 during
device operation. In the orientation of FIG. 2, the media
interfacing surface 202 is arranged parallel to the x-z plane. A
waveguide 206 may be disposed proximate the NFT 112, which is
located at or near the media writing surface 214.
[0028] The NFT 112, waveguide 206, and other components are built
on a substrate plane, which is parallel to the x-y plane in this
view. Waveguide 206 is shown configured as a planar waveguide, and
is surrounded by cladding layers (not shown) that have different
indices of refraction than a core of the waveguide 206. Other
waveguide configurations may be used instead of a planar waveguide,
e.g., channel waveguide. Light propagates through the waveguide
206. Electrical field lines emanate from the waveguide 206 and
excite the NFT 112. The NFT 112 delivers surface plasmon-enhanced,
near-field electromagnetic energy along the negative y-direction
where it exits at the media interfacing surface 202. This may
result in a highly localized hot spot (not shown) on the magnetic
recording media 204. A magnetic recording pole 215 that is located
alongside NFT 112. The magnetic recording pole 215 generates a
magnetic field (e.g., perpendicular field) used in changing the
magnetic orientation of the hotspot during writing.
[0029] Many NFT designs include an enlarged region as well a peg
region. The enlarged region will typically comprise substantially
90% or more of the volume of the NFT in some embodiments. Although
discussed as a separate region or portion, typically the peg region
is integrally fabricated of a same material as the enlarged region.
The specific wavelength of light from the laser diode dictates the
size of the enlarged region of the NFT and a length of the peg
region in order to get optimal (maximum) coupling efficiency of the
laser light to the NFT.
[0030] As discussed previously, the peg region acts as the writing
tip of the NFT while the enlarged region is configured to receive
concentrated light from the laser diode/waveguide and is designed
to help NFT achieve surface plasmon resonance in response to this
concentration of light. The peg region is in optical and/or
electrical communication with the enlarged region and creates a
focal point for the energy received by the enlarged region.
[0031] As is known, temperature increases in the peg region are a
challenge for the durability of HAMR devices. A temperature
mismatch between the relatively higher temperature peg region and
relatively lower temperature enlarged region as well as mechanical
stresses are thought to lead to an exchange of material (and
vacancies) between the two regions. As used herein, the term
"material" additionally includes any vacancies within the material.
The temperature mismatch between the two regions as wells as the
mechanical stresses are thought to be phenomenon that drive peg
deformation and peg recession, which can lead to failure of the
HAMR device.
[0032] The present disclosure relates to apparatuses, systems, and
methods related to an NFT for the HAMR device. In particular,
embodiments of the NFT include a peg region that is separated from
the remainder of the NFT by a barrier material. This encapsulation
of the peg region from the remainder of the NFT reduces or
eliminates interdiffusion of material between the peg region and
the remainder of the NFT. The reduction or elimination of
interdiffusion of material reduces the likelihood of peg recession
and failure of the HAMR device.
[0033] FIG. 3 shows a cross-sectional view of one embodiment of an
NFT 312. FIG. 3A is a second cross-sectional view of the NFT 312.
As illustrated in FIGS. 3 and 3B, the NFT 312 includes a peg region
302, an enlarged region 304, and a barrier material 306.
Additionally, the peg region 302 includes surfaces 308a, 308b,
308c, and 308d and the enlarged region 304 includes arcuate surface
310 and bottom surface 314.
[0034] The enlarged region 304 is disposed adjacent the peg region
302. The barrier material 306 is disposed between the peg region
302 and the enlarged region 304 to reduce or eliminate
interdiffusion of materials between the peg region 302 and the
enlarged region 304. However, the peg region 302 remains in optical
and/or electrical communication with the enlarged region 304.
[0035] The peg region 302 can extend from the enlarged region 304
toward media-facing surface (e.g., media interfacing surface 202 in
FIG. 2). In the illustrated embodiment, the enlarged region 304 has
a circular disk shape. In the context of describing the shape of
the enlarged region 304, the term "disk" refers to
three-dimensional shapes that include a cylindrical or tapered
cylindrical portion, a bottom surface 314, and a top surface. Thus,
the disk shape can include a truncated conical shape in some
instances. The bottom surface 314 may or may not be arranged in a
plane parallel with the top surface. The peg region 302 and the
enlarged region 304 can be formed from a thin film of plasmonic
metal (e.g., aluminum, gold, silver, copper, and combinations or
alloys thereof) on a substrate plane of the slider proximate the
write pole (e.g., magnetic recording pole 215 in FIG. 2). In some
embodiments, the peg region 302 and the enlarged region 304 can be
formed from the same material.
[0036] The barrier material 306 is disposed between the peg region
302 and the enlarged region 304, and in particular, is arranged to
substantially separate (encapsulate) the peg region 302 from the
enlarged region 304. As illustrated in FIGS. 3 and 3A, the barrier
material 306 can be disposed on a portion of the peg region 302
opposing the surface 308a (i.e., a non-media interfacing end of the
peg region 302). The length, thickness, and other dimensional and
physical properties of the barrier material 306 will depend upon
the composition of the peg region and enlarged region and upon the
specific wavelength of light from the laser diode. In one
embodiment the barrier material 306 has a thickness of between
about 1.0 nm and about 10.0 nm.
[0037] As illustrated, the barrier material 306 disposed along a
side of the peg region 302 can have thicknesses t.sub.1 that differ
from a thickness t.sub.2 of the barrier material 306 disposed along
a top of the peg region 302 and/or a thickness t.sub.3 of the
barrier material 306 disposed along a non-media interfacing back of
the peg region 302. The barrier material 306 can be comprised of
one or more of ZrN, TiN, Rh, Zr, Hf, Ru, AuN, TaN, Ir, W, Mo, Co,
and alloys thereof. It is desirable that barrier material 306
create a diffusion barrier for Au and other plasmonic metals and
have a thermal conductivity greater than about 10 W/m-K in some
embodiments. It is also desirable in some instances that barrier
material 306 has appreciable optical figure of merit. Although best
described as a layer in some embodiments, barrier material 306 can
include one or more layers or can be a component that is not
layered in nature in some instances.
[0038] As shown in FIGS. 3 and 3A, the barrier material 306
encapsulates the peg region 302 by extending between the arcuate
surface 310 and the bottom surface 314 of enlarged region 304. In
the embodiment illustrated, the barrier material 306 extends along
a plane that substantially aligns with surfaces 308b, 308c, and
308d of the peg region 302. However, in other embodiments the
barrier material 306 may not substantially align with surfaces
308b, 308c, and 308d. As will be discussed subsequently, the
barrier material 306 is fabricated to be self-aligned using
electro-deposition, plasma treatment/annealing, dopant/annealing,
and/or plasma treatment/electrochemical processing etc. The
self-aligned fabrication methods allow the barrier material 306 to
be disposed substantially only between the peg region 302 and the
enlarged region 304 according to various embodiments.
[0039] FIGS. 4 and 4A show another embodiment of an NFT 412
fabricated using non-self-aligned methods. FIG. 4 shows a first
cross-sectional view of the NFT 412. FIG. 4A is a second
cross-sectional view of the NFT 412. As illustrated in FIGS. 4 and
4B, the NFT 412 includes a peg region 402, an enlarged region 404,
and a barrier material 406. Additionally, the peg region 402
includes surfaces 408a, 408b, 408c, and 408d and the enlarged
region 404 includes an arcuate surface 410 and bottom surface
414.
[0040] The general characteristics of the NFT 412 have been
previously described in reference to the NFT 312 of FIGS. 3 and 3A,
and, therefore, will not be described in great detail. However, the
embodiment of FIGS. 4 and 4A differs from that of FIGS. 3 and 3A in
that the barrier material 406 is disposed between the enlarged
region 404 and the peg region 402 and is additionally disposed
along the arcuate surface 410 and the bottom surface 414 of the
enlarged region 404. In FIGS. 4 and 4A, the barrier material 406 is
fabricated to be non-self-aligned using known lithography methods,
e.g. sputtering. The non-self-aligned fabrication methods allow the
barrier material 406 to be disposed between the enlarged region 404
and the peg region 402 and along one or more additional surfaces of
the enlarged region 404.
[0041] FIG. 5 shows a cross-sectional view of another embodiment of
an NFT 512 and a spacing element 516. FIG. 5A is a second
cross-sectional view of the NFT 512 and the spacing element 516. As
illustrated in FIGS. 5 and 5A, the NFT 512 includes a peg region
502, an enlarged region 504, and a barrier material 506.
Additionally, the peg region 502 includes surface 508a and the
enlarged region 504 includes arcuate surface 510 and bottom surface
514.
[0042] The general characteristics of the NFT 512 have been
previously described in reference to the NFT 512 of FIGS. 5 and 5A,
and, therefore, will not be described in great detail. However, the
embodiment of FIGS. 5 and 5A differs from that of FIGS. 3 and 3A in
that the barrier material 506 is disposed between enlarged region
504 and peg region 502 and is additionally disposed between the NFT
512 and the spacing element 516. The spacing element 516 is
disposed to interface with the peg region 502 and extends between
the enlarged region 504 and a pole (e.g., the magnetic recording
pole 215 of FIG. 2). In the illustrated embodiment, the spacing
element 516 is dispose around several side surfaces (e.g., surfaces
308a, 308b, and 308c in FIGS. 3 and 3A) but does not contact peg
region 502 as barrier material 506 is disposed therebetween. Thus,
only the surface 508a, as well as a bottom surface of the peg
region 502 are not encapsulated by the barrier material 506. The
spacing element 516, also called a NFT to pole spacing ("NPS"), can
be formed by a deposition process in some instances, and can be
comprised of an electrically insulating material. It is also
desirable in some instances that spacing element 516 has
appreciable optical figure of merit.
[0043] FIG. 6 illustrates a one step in a method of fabricating an
NFT. As illustrated in FIG. 6, the peg region 602 is formed using
known lithography methods prior to formation of the enlarged
region. A sacrificial material 620, such as a photoresist, is
disposed over a first portion 622 of the peg region 602, leaving a
second portion 624 of the peg region 602 exposed. A barrier
material 606 is fabricated over the second portion 624 of the peg
region 602.
[0044] In one embodiment, the barrier material 606 is fabricated
using a vacuum deposition (dc/rf/reactive sputtering, ion beam
deposition, evaporation) or an electroplating process that disposes
a metal such as Rh, Zr, Hf, Ru, Ir, W, Mo, Co and alloys thereof
over one or more surfaces of the second portion 624. In another
embodiment, the barrier material 606 is fabricated by applying a
nitride forming compound such as Zr, Ti, Au, Ta, W in low
concentrations, i.e., <1 by weight %. In some embodiments,
nitrides formed with the disclosed compounds act as an effective
diffusion barrier when they form stoichiometric nitrides having the
lowest achievable resistivity and highest achievable optical figure
of merit to the peg region 602. The nitride forming compound can be
applied as a diffuse dopant or as a layer in the formation of the
peg region 602. The exposed second portion 624 containing the
nitride forming compound can be annealed in nitrogen or nitrogen
plasma at or relatively near atmospheric pressure at a temperature
between about 100.degree. C. and about 400.degree. C. for a
duration of up to several hours. The annealing process causes the
nitride forming compound to form nitrides such as ZrN, TiN, AuN,
TaN, WN along the one or more surfaces of the second portion 624
(i.e., the surfaces exposed to the nitrogen or nitrogen plasma). In
yet another embodiment, the barrier material 606 can be comprised
of AuN and is fabricated by annealing the exposed second portion
624 of the peg region 602 in nitrogen or nitrogen plasma at or
relatively near atmospheric pressure at a temperature between about
100.degree. C. and about 400.degree. C. for a duration of up to
several hours. In another embodiment, the barrier material 606 can
be comprised of AuO and is fabricated either electrochemically or
by annealing the exposed second portion 624 of the peg region 602
in oxygen or oxygen plasma at or relatively near atmospheric
pressure at a temperature between about 100.degree. C. and about
400.degree. C. for a duration of up to several hours.
[0045] The enlarged region (e.g., the enlarged region 304 of FIGS.
3, 3A) is formed between the portions of the sacrificial material
620. Thus, the enlarged region is disposed adjacent and along the
second portion 624 of the peg region 602 such that the barrier
material 606 is disposed at least between the second portion 624
and the enlarged region (not shown in FIG. 6) to reduce
interdiffusion between the peg region 602 and the enlarged region.
After formation of the enlarged region 604, the sacrificial
material 620 can be removed using lithography processes such as ion
milling and other techniques.
[0046] Although specific embodiments have been illustrated and
described herein, it will be appreciated by those of ordinary skill
in the art that a variety of alternate and/or equivalent
implementations can be substituted for the specific embodiments
shown and described without departing from the scope of the present
disclosure. This application is intended to cover any adaptations
or variations of the specific embodiments discussed herein.
Therefore, it is intended that this disclosure be limited only by
the claims and the equivalents thereof. All references cited within
are herein incorporated by reference in their entirety.
* * * * *