U.S. patent application number 17/684860 was filed with the patent office on 2022-06-16 for industrial equipment article.
The applicant listed for this patent is SILCOTEK CORP.. Invention is credited to James B. MATTZELA, Paul H. SILVIS, David A. SMITH, Min YUAN.
Application Number | 20220186040 17/684860 |
Document ID | / |
Family ID | 1000006170178 |
Filed Date | 2022-06-16 |
United States Patent
Application |
20220186040 |
Kind Code |
A1 |
SMITH; David A. ; et
al. |
June 16, 2022 |
INDUSTRIAL EQUIPMENT ARTICLE
Abstract
Industrial equipment articles and thermal chemical vapor coated
articles are disclosed. The articles include a coating on a
substrate of the industrial equipment article, the coating
including silicon, carbon, and hydrogen. The industrial equipment
article requires resistance to protein adsorption. The industrial
equipment article was heated during application of the coating to a
temperature of between 300 degrees C. and 600 degrees C. The
thermal chemical vapor coated article includes a coating on the
thermal chemical vapor coated article, the coating formed by
thermal decomposition, oxidation, then functionalization. The
thermal chemical vapor coated article is industrial equipment
requiring resistance to protein adsorption. The coating is
resistant to the protein adsorption and is on a substrate heated
during the thermal decomposition.
Inventors: |
SMITH; David A.;
(Bellefonte, PA) ; YUAN; Min; (State College,
PA) ; MATTZELA; James B.; (Port Matilda, PA) ;
SILVIS; Paul H.; (Port Matilda, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SILCOTEK CORP. |
Bellefonte |
PA |
US |
|
|
Family ID: |
1000006170178 |
Appl. No.: |
17/684860 |
Filed: |
March 2, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14680669 |
Apr 7, 2015 |
11292924 |
|
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17684860 |
|
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61976789 |
Apr 8, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y10T 428/31663 20150401;
Y10T 428/31612 20150401; Y10T 428/13 20150115; C09D 5/16 20130101;
C23C 16/0227 20130101; C09D 5/1625 20130101; C23C 16/44 20130101;
C23C 16/30 20130101; A61L 2420/02 20130101; Y10T 428/263 20150115;
C23C 16/56 20130101 |
International
Class: |
C09D 5/16 20060101
C09D005/16; C23C 16/44 20060101 C23C016/44; C23C 16/56 20060101
C23C016/56; C23C 16/02 20060101 C23C016/02; C23C 16/30 20060101
C23C016/30 |
Claims
1. An industrial equipment article, comprising: a coating on a
substrate of the industrial equipment article, the coating
including silicon, carbon, and hydrogen; wherein the industrial
equipment article requires resistance to protein adsorption;
wherein the substrate of the industrial equipment article was
heated during application of the coating to a temperature of
between 300 degrees C. and 600 degrees C.
2. The industrial equipment article of claim 1, wherein the
application of the coating is by thermal decomposition, oxidation,
then functionalization.
3. The industrial equipment article of claim 2, wherein the
oxidation is by introduction of zero air.
4. The industrial equipment article of claim 2, wherein the
functionalization is by introduction of trimethylsilane.
5. The industrial equipment article of claim 1, wherein the
substrate is stainless steel.
6. The industrial equipment article of claim 5, wherein the
stainless steel includes 316 stainless steel.
7. The industrial equipment article of claim 1, wherein the
substrate is titanium.
8. The industrial equipment article of claim 1, wherein the
substrate is a composite metal.
9. The industrial equipment article of claim 1, wherein the
substrate is glass.
10. The industrial equipment article of claim 1, wherein the
substrate is a fiber substrate or a foil substrate.
11. The industrial equipment article of claim 1, wherein the
coating is positioned in a tube, the tube having an internal
diameter of between 1 millimeter and 3 millimeters.
12. The industrial equipment article of claim 1, wherein the
coating is positioned in a tube, the tube having an internal
diameter of less than 3 millimeters.
13. The industrial equipment article of claim 1, wherein the
coating is positioned in a tube, the tube having an internal
diameter of between 0.1 millimeter and 1 millimeters.
14. The industrial equipment article of claim 1, wherein the
coating is positioned in a tube, the tube having an internal
diameter of between 0.1 millimeter and 3 millimeters.
15. The industrial equipment article of claim 1, wherein the
coating has a thickness of between about 100 nm and about 1,000
nm.
16. The industrial equipment article of claim 1, wherein the
coating is amorphous.
17. The industrial equipment article of claim 1, wherein the
coating includes an amorphous array of Si--C bonds.
18. The industrial equipment article of claim 1, wherein the
thermal decomposition is by introduction of dimethylsilane.
19. A thermal chemical vapor coated article, comprising: a coating
on the thermal chemical vapor coated article, the coating formed by
thermal decomposition, oxidation then functionalization; wherein
the thermal chemical vapor coated article is industrial equipment
requiring resistance to protein adsorption; wherein the coating is
resistant to the protein adsorption and is on a substrate heated
during the thermal decomposition.
20. A thermal chemical vapor coated article, comprising: a coating
on the thermal chemical vapor coated article, the coating formed by
thermal decomposition on a stainless steel surface, oxidation then
functionalization; wherein the thermal chemical vapor coated
article is industrial equipment requiring resistance to protein
adsorption; wherein the coating is resistant to the protein
adsorption and is on a substrate heated during the thermal
decomposition; wherein the thermal decomposition is by introduction
of dimethylsilane; wherein the oxidation is by introduction of zero
air; and wherein the functionalization is by introduction of
trimethylsilane.
Description
PRIORITY
[0001] This application is a non-provisional continuation patent
application claiming priority and benefit of U.S. Provisional
Patent Application No. 61/976,789, entitled "COATED ARTICLE," along
with U.S. Non-Provisional patent application Ser. No. 14/680,669,
entitled "THERMAL CHEMICAL VAPOR DEPOSITION COATED ARTICLE AND
PROCESS" and now pending issuance, both of which are hereby
incorporated by reference in their entirety.
FIELD
[0002] The present disclosure is directed to coated articles and
coating processes. More particularly, the disclosure is directed to
industrial equipment articles coated with thermal chemical vapor
deposition coatings.
BACKGROUND
[0003] Often, surfaces of substrates do not include desired
performance characteristics. The failure to include specific
desired performance characteristics can result in surface
degradation in certain environments, an inability to meet certain
performance requirements, or combinations thereof. Biofouling
and/or biocontamination presents a severe challenge in a wide range
of applications from biomedical devices and protective apparel in
hospitals, medical implants, biosensors, food packaging and
storage, water purification systems, to marine and industrial
equipment. For example, in marine applications, biofoulants, such
as, algae, barnacles, tunicates, and mussels frequently invade ship
hulls, piers, offshore oil and gas platforms. Such biofoulants
cause increased drag and damage of materials, which results in
billion dollars of cost due to decreased fuel efficiency.
[0004] Another problem, known as protein adsorption exists in the
human body, affecting contact lenses, endotracheal tubes,
artificial joints, biomedical implants, and other similar devices.
Protein adsorption involves protein sticking to surfaces of
biomedical devices. This causes millions of contact lens infections
every year and requires heart patients to take anti-clotting drugs.
Adsorption of proteins to biological sampling systems also reduces
sensitivity in the case of in vitro diagnostics.
[0005] In general, an inert surface resistant to biofouling is
needed. However, existing solutions to biofouling have significant
drawbacks. For example, the most commonly used substances to impart
protein resistance to a surface are based on oligo(ethylene glycol)
or poly(ethylene glycol) (PEG). However, such substances are not
stable and have a tendency to auto-oxidize in the presence of
oxygen, thereby losing protein-resistance.
[0006] In marine applications, current anti-fouling strategies
utilize paints or coatings having heavy metals that gradually
dissolve and release toxic substances like copper, tin, zinc or
organic biocides. Such toxic substances poison everything and
anything that attaches to a ship hull. The environmental concerns
have prompted the international maritime community to ban tin-based
marine coatings on newly built vessels, and United States Navy
standards require that replacement coatings be environmentally
benign and stable for ten to twelve years.
[0007] Accordingly, a coated article that does not suffer from one
or more of the above drawbacks would be desired in the art.
SUMMARY
[0008] According to an embodiment of the present disclosure, an
industrial equipment article includes a coating on a substrate of
the industrial equipment article, the coating including silicon,
carbon, and hydrogen. The industrial equipment article requires
resistance to protein adsorption. The substrate of the industrial
equipment article was heated during application of the coating to a
temperature of between 300 degrees C. and 600 degrees C.
[0009] According to an embodiment of the present disclosure, a
thermal chemical vapor coated article includes a coating on the
thermal chemical vapor coated article, the coating formed by
thermal decomposition, oxidation then functionalization. The
thermal chemical vapor coated article is industrial equipment
requiring resistance to protein adsorption. The coating is
resistant to the protein adsorption and is on a substrate heated
during the thermal decomposition.
[0010] Further aspects of embodiments of the invention are
disclosed herein. The features as discussed above, as well as other
features and advantages of the present application, will be
appreciated and understood by those skilled in the art from the
following drawings and detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a schematic view of an article having a coating
with a layer formed from decomposition of a material according to
an embodiment of the disclosure.
[0012] FIG. 2 shows a schematic view of a process according to an
embodiment of the disclosure.
[0013] FIG. 3 shows a schematic view of an article having a coating
with an oxidized layer formed according to an embodiment of the
disclosure.
[0014] FIG. 4 shows a schematic view of an article having a coating
with an oxidized-then-functionalized layer formed according to an
embodiment of the disclosure.
[0015] FIG. 5 shows a schematic view of an article having a coating
with an oxidized-then-functionalized layer formed according to an
embodiment of the disclosure.
[0016] FIG. 6 shows an Auger Electron Spectroscopy plot of an
article having a layer formed from decomposition of material
according to an embodiment of the disclosure.
[0017] FIG. 7 shows an Auger Electron Spectroscopy plot of an
article having a layer formed from decomposition of material
followed by oxidation with water according to an embodiment of the
disclosure.
[0018] Wherever possible, the same reference numbers will be used
throughout the drawings to represent the same parts.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0019] U.S. patent application Ser. No. 13/504,533, filed Apr. 27,
2012, and titled "Coating, Coated Article, and Method of Applying a
Coating," is hereby incorporated by reference in its entirety.
Provided is a coating, a coated article, and a chemical vapor
deposition process for producing a coated article. Embodiments of
the present disclosure permit coatings, for example, in comparison
to similar coatings failing to include one or more of the features
disclosed herein, to include additional properties relating to
having protein resistance and general anti-biofouling properties,
having consistent or substantially consistent thickness within tube
or tube-like articles, being devoid or substantially devoid of
build up in entrances of the tube or tube-like articles, or a
combination thereof.
[0020] In one embodiment, a coating 101 (see FIG. 1) is resistant
to fouling conditions. As used herein, "fouling conditions" refer
to conditions that are present in the presence of micro-organisms,
such as, alga, barnacles, tunicates, and mussels that frequently
invade ship hulls, piers, offshore oil and gas platforms. In
further embodiments, the coating is more resistant to such
conditions than uncoated alloys, teflon, stainless steel, or a
combination thereof.
[0021] In one embodiment, the coating 101 is resistant to protein
adsorption conditions. As used herein, "protein adsorption
conditions" refer to conditions with protein at a concentration
that is capable of adsorption to a stainless steel surface.
[0022] A coating process 200 (see FIG. 2) forms the coating 101 on
a substrate 100 of an article 103, for example, as is shown in FIG.
1. The article 103 is any suitable object that benefits from
anti-fouling properties but is capable of withstanding processing
temperatures of the coating process 200. Suitable objects include,
but are not limited to, biomedical devices, surgical equipment,
medical diagnostic sampling systems, medical implants, parts of
marine and/or industrial equipment, coastal marine structures,
offshore structures, ocean/island vessels, similar objects, or
combinations thereof.
[0023] For example, in one embodiment, the article 103 is a
coronary stent (a small metal mesh tube that acts as a scaffold to
provide support inside the coronary artery). The coronary stent is
created by any suitable technique, such as, within a coil, tubular
mesh, or slotted tube framework. In a further embodiment, the
coronary stent includes a strut pattern, strut width, a diameter
(for example, between 2 and 6 mm), length (for example, between 8
mm and 50 mm), or a combination thereof. In one embodiment, the
article 103 is a medical-grade probe, such as, a 316 stainless
steel probe. The medical-grade probe has an internal diameter (for
example, at or greater than 0.1 mm, between 1 mm and 3 mm, or any
suitable combination, sub-combination, range, or sub-range
thereof). The medical-grade probe is capable of use in a medical
diagnostic system.
[0024] The article 103 includes a surface 105, which is or includes
the interior surface, an exterior surface, or a combination
thereof. The surface 105 has surface properties achieved through
the coating process 200 controllably depositing a layer 102. The
layer 102 imparts a surface effect to the substrate 100, the
coating 101, the article 103, or combinations thereof. The
substrate 100 is any suitable substrate, such as, a metallic
substrate (ferrous or non-ferrous), stainless steel, titanium, a
glass substrate, a ceramic substrate, ceramic matrix composite
substrate, a composite metal substrate, a coated substrate, a fiber
substrate, a foil substrate, a film, or a combination thereof.
[0025] Referring to FIG. 2, the coating process 200 includes
pretreatment (step 202), thermal decomposition (step 204),
oxidation (step 208), post-oxidation functionalization (step 210),
or a combination thereof. In one embodiment, the coating process
200 includes, consist of, or consists essentially of the
pretreatment (step 202) and the thermal decomposition (step 204).
In one embodiment, the coating process 200 includes, consist of, or
consists essentially of the thermal decomposition (step 204), the
oxidation (step 208), and the post-oxidation functionalization
(step 210). In one embodiment, the coating process 200 includes,
consist of, or consists essentially of the pretreatment (step 202),
the thermal decomposition (step 204), the oxidation (step 208), and
the post-oxidation functionalization (step 210).
[0026] The pretreatment (step 202) is or includes any suitable
techniques taken to prepare a chamber, the surface 105, the
substrate 100, or a combination thereof. In one embodiment, the
chamber is a chemical vapor deposition chamber, for example, with
tubing connections to allow gas flow in and out of the chemical
vapor deposition chamber. In a further embodiment, the chamber
includes multiple controlled inlets and outlets configured for
providing and removing multiple gas streams and/or a vacuum
connected to one or more outlet tubes.
[0027] Suitable techniques for the pretreatment (step 202) include,
but are not limited to, cleaning, pre-heating, isolating the
substrate 100 and/or the surface 105, surface treatment techniques,
evacuating the chamber (for example, with the flow of gas and/or
maintenance of a vacuum in the chamber providing a controlled
atmosphere), flushing/purging the chamber (for example, with an
inert gas such as nitrogen, helium, and/or argon), or a combination
thereof. In one embodiment, a heat source controls the temperature
in the chamber, for example, to desorb water and remove
contaminants from the surface 105. In one embodiment, the heating
is at a temperature above about 100.degree. C. (for example, about
450.degree. C.) and/or at a pressure (for example, between about 1
atmosphere and about 3 atmospheres, between about 1 atmosphere and
about 2 atmospheres, between about 2 atmospheres and about 3
atmospheres, about 1 atmosphere, about 2 atmospheres, about 3
atmospheres, or any suitable combination, sub-combination, range,
or sub-range therein). In one embodiment, the heating is for a
period of time (for example, between about 3 minutes and about 15
hours, between about 0.5 hours and about 15 hours, for about 3
minutes, for about 0.5 hours, for about 2 hours, for about 15
hours, or any suitable combination, sub-combination, range, or
sub-range therein).
[0028] In one embodiment, the pretreatment (step 202) includes
pre-exposure of the substrate 100 to a thermal oxidative
environment. Pre-exposure of the substrate 100 to the thermal
oxidative environment pre-oxidizes the surface 105 of the substrate
100, increasing stability of both the surface 105 and the substrate
100. The increased stability of the substrate 100 increases the
stability of the coating 101 formed over the substrate 100.
[0029] The thermal oxidative environment is at any suitable
temperature(s) allowing oxidation. Suitable temperatures include,
but are not limited to between about 100.degree. C. and about
700.degree. C., between about 100.degree. C. and about 450.degree.
C., between about 100.degree. C. and about 300.degree. C., between
about 200.degree. C. and about 500.degree. C., between about
300.degree. C. and about 600.degree. C., between about 450.degree.
C. and about 700.degree. C., about 700.degree. C., about
450.degree. C., about 100.degree. C., or any suitable combination,
sub-combination, range, or sub-range thereof.
[0030] The substrate 100 is pre-exposed to the thermal oxidative
environment for any suitable duration allowing oxidation. Suitable
duration including, but are not limited to, between about 30
minutes and 6 hours, between about 30 minutes and about 4 hours,
between about 1 hour and about 4 hours, up to about 10 hours, up to
about 4 hours, up to about 2 hours, up to about 30 minutes, or any
combination, sub-combination, range or sub-range thereof.
[0031] The increased stability of the coating 101 is detectable by
contact angle measurements for both water and hexadecane, for
example, after exposure of the substrate 100 to room air at
450.degree. C. for 30 minutes. In one embodiment, the substrate 100
is X40CrMoV5-1 having a composition including by weight percent
between about 0.37% and about 0.42% carbon, between about 0.90% and
about 1.20% silicon, between about 0.30% and about 0.50% manganese,
up to about 0.030% phosphorous, up to about 0.030% sulfur, between
about 4.80% and about 5.50% chromium, between about 1.20% and about
1.50% molybdenum, between about 0.90% and about 1.10% vanadium, the
rest being substantially iron.
[0032] In another embodiment, without pre-oxidation of the
substrate 100, the contact angle of water on X40CrMoV5-1 after 30
minutes of exposure to 450.degree. C. in room air drops to
28.8.degree. from an initial value of 146.9.degree., a
118.1.degree. change. However, with pre-oxidation of the substrate
100, the contact angle of water on X40CrMoV5-1 after 30 minutes of
exposure to 450.degree. C. in room air increases to 127.4.degree.
from an initial value of 126.2.degree., a 1.2.degree. change. In
another example, without pre-oxidation the contact angle of
hexadecane on X40CrMoV5-1 after 30 minutes of exposure to
450.degree. C. in room air drops to approximately 0.degree. from an
initial value of 92.3.degree., a 92.3.degree. change. However, with
pre-oxidation, the contact angle of hexadecane on X40CrMoV5-1 after
30 minutes of exposure to 450.degree. C. in room air increases to
72.1.degree. from an initial value of 66.5.degree., a 5.6.degree.
change.
[0033] The thermal decomposition (step 204) is or includes thermal
decomposition of one or more precursor materials. In one
embodiment, the precursor material is or includes dimethylsilane,
for example, in gaseous form. In general, dimethylsilane is not
readily obtainable due to the low demand for it. Dimethylsilane has
been regarded as undesirable in some chemical vapor deposition
applications because it includes carbon and is much more expensive
than silane. Silane and the monomethyl analogue to dimethylsilane,
methylsilane, are both pyrophoric and may explode in air.
Dimethylsilane, although flammable, is not pyrophoric. Thus, use of
dimethylsilane decreases safety risks. In addition, use of
dimethylsilane results in inertness of a coating and/or chemical
resistance, thereby protecting the surface 105 of the substrate
100. Other suitable precursor materials include, but are not
limited to, trimethylsilane, dialkylsilyl dihydride, alkylsilyl
trihydride, and combinations thereof. In one embodiment, the
materials are non-pyrophoric, for example, dialkylsilyl dihydride
and/or alkylsilyl trihydride.
[0034] The thermal decomposition (step 204) includes any suitable
thermal decomposition parameters corresponding to the precursor
material, for example, as is described in U.S. Pat. No. 6,444,326,
which is incorporated herein by reference in its entirety, to apply
material through deposition. If a thicker deposition of the layer
102 is desired, the deposition temperature, the deposition
pressure, the deposition time, or a combination thereof are
increased or decreased. Suitable thicknesses of the coating 101
include, but are not limited to, between about 100 nm and about
10,000 nm, between about 200 nm and about 5,000 nm, between about
300 nm and about 1,500 nm, or any suitable combination,
sub-combination, range, or sub-range therein.
[0035] Additionally or alternatively, in one embodiment, a
plurality of the layers 102 are applied by repeating the
deposition. In one embodiment, the thermal decomposition (step 204)
pressure is between about 0.01 psia and about 200 psia, 1.0 psia
and about 100 psia, 5 psia and about 40 psia, about 1.0 psia, about
5 psia, about 40 psia, about 100 psia, 200 psia, or any suitable
combination, sub-combination, range, or sub-range therein. In one
embodiment, the thermal decomposition (step 204) temperature is
between about 200.degree. C. and 600.degree. C., between about
300.degree. C. and 600.degree. C., between about 400.degree. C. and
about 500.degree. C., about 300.degree. C., about 400.degree. C.,
about 500.degree. C., about 600.degree. C., or any suitable
combination, sub-combination, range, or sub-range therein. In one
embodiment, the thermal decomposition (step 204) period is for a
duration of about 10 minutes to about 24 hours, about 30 minutes to
about 24 hours, about 10 minutes, about 30 minutes, about 15 hours,
about 24 hours, or any suitable combination, sub-combination,
range, or sub-range therein.
[0036] The thermal decomposition (step 204) forms the layer 102,
for example, having improved chemical resistance, improved
inertness, and/or improved adhesion over non-diffusion coatings
and/or coatings not having the thermally decomposed material. The
layer 102 includes any suitable thermally decomposed material
corresponding to the precursor material. The thermally decomposed
material is formed by the thermal decomposition (step 204) at a
pressure and a temperature sufficient to decompose the precursor
material, thereby depositing constituents from the thermally
decomposed material onto the substrate 100, for example, with an
inert gas such as nitrogen, helium, and/or argon, as a partial
pressure dilutant.
[0037] In one embodiment, the thermally decomposed material is or
includes carbosilane (for example, amorphous carbosilane),
corresponding to the precursor including the dimethylsilane, which,
although not intending to be bound by theory, is believed to be a
recombination of carbosilyl (disilyl or trisilyl fragments) formed
from the carbosilane. In one embodiment, the thermally decomposed
material includes molecules, such as, silicon, carbon, and hydrogen
atoms, that serve as active sites. The molecules are positioned
within the layer 102 and include a first portion 104 and a second
portion 106. Generally, the first portion 104 and the second
portion 106 of the layer 102 are not spatially resolvable (for
example, the first portion 104 and the second portion 106 are
defined by the molecules deposited on the layer 102 and the
molecules are capable of being interspersed throughout the layer
102). Furthermore, use of the terms "first" and "second" is not
intended to imply any sequentiality, difference in quantity,
difference in size, or other distinction between the two portions.
To the contrary, the terms "first" and "second" are used for
distinguishing molecular composition of the two portions. For
example, in one embodiment, as is shown in FIG. 1, the first
portion 104 includes silicon and the second portion 106 includes
carbon. In one embodiment, the first portion 104 and the second
portion 106 are bound together randomly throughout the layer
102.
[0038] FIG. 6 shows the composition of an embodiment throughout the
article 103 by Auger Electron Spectroscopy measurements according
to an embodiment of the disclosure. FIG. 6 shows a diffusion region
108 within the article 103. It will be appreciated that precise
measurement of the diffusion layer 108 via Auger Electron
Spectroscopy can be offset by surface roughness of the substrate
and coating and that the results shown are merely representative of
one embodiment falling within the disclosure. Therefore, the
diffusion region 108, as measured by Auger Electron Spectroscopy,
is not an absolute measurement but a representation of the
diffusion mechanism, according to the coating process 200.
[0039] In one embodiment, the composition of the layer 102 is about
1:0.95:0.12 ratio of C:Si:O. In contrast, the composition of the
dimethylsilane introduced into the chemical vapor deposition
chamber according to an embodiment has about a 2:1 ratio of C:Si.
Although not intending to be bound by theory, it is believed that
CH.sub.x (x=0-3) moieties are retained and Si--C bonds are broken
thus indicating that layer 102 includes an amorphous array of Si--C
bonding. The amorphous array provides additional benefits such as
decreased cracking or flaking, for example, upon tensile or
compressive forces acting on the substrate 100, increased adhesion,
or a combination thereof. In one embodiment, multiple layers of the
coating 101, or similar coatings, are deposited for thicker layers
or for desired properties.
[0040] In one embodiment, upon the thermally decomposed materials
forming the layer 102 through the thermal decomposition (step 204),
the chamber is purged. The purging removes remaining decomposition
materials, unbound thermally decomposed materials, and/or other
materials or constituents present within the chamber.
[0041] The oxidation (step 208) is or includes exposure to any
suitable chemical species or oxidation reagent capable of donating
a reactive oxygen species under oxidation conditions to form the
oxidized layer 107. The oxidation (step 208) is of the layer 102
and forms the oxidized layer 107. In an embodiment with the layer
102 being amorphous carbosilane, the oxidized layer 107 formed by
the oxidation (step 208) is or includes amorphous carboxysilane. In
general, the oxidation (step 208) are bulk reactions that affect
the bulk of the coating 101. In one embodiment, the degree of
oxidization is controlled by increasing or decreasing the
temperature within the chamber, the exposure time within the
chamber, the type and/or amount of diluent gases, pressure, and/or
other suitable process conditions. Control of the degree of the
oxidization increases or decreases the amount and/or depth of the
oxidized layer 107 and, thus, the wear resistance and/or hardness
of the coating 101.
[0042] Suitable oxidation reagents for the oxidation (step 208)
include, but are not limited to, water (alone, with zero air, or
with an inert gas), oxygen, air (alone, not alone, and/or as zero
air), nitrous oxide, ozone, peroxide, or a combination thereof. As
used herein, the term "zero air" refers to atmospheric air having
less than about 0.1 ppm total hydrocarbons. In one embodiment, the
oxidation reagent consists of gaseous reagents. Due to the gaseous
processing agents (for example, dimethylsilane and/or nitrogen)
being in the gas phase, use of the gaseous oxidation reagent
results in simpler scale-up for manufacturing, a more transferable
process, and a more economical process.
[0043] The oxidation reagent used for the oxidation (step 208) is
introduced at any suitable operational conditions permitting the
formation of the oxidized layer 107. Suitable operational
conditions include, but are not limited to, being in the presence
of an inert gas, being at a pressure (for example, between about 1
to 200 psia), being subjected to a temperature (for example, about
450.degree. C.), being for a period of time (for example, for about
two hours), other parameters as are described above with reference
to the thermal decomposition (step 204), or a combination
thereof.
[0044] In one embodiment, depending upon the selected species of
the oxidation reagent, additional features are present, for
example, for safety purposes. Such features include the chamber
having a size, weight, and/or corrosion-resistance permitting
reactions to occur safely. In one embodiment, to safely inject
water into the chamber as the oxidation reagent, substantial
cooling is used. For example, in embodiments with the chamber
operating at temperature of greater than about 300.degree. C., the
chamber is first cooled below about 100.degree. C., which is
capable of resulting in a drain on energy and/or time of
manufacturing resources.
[0045] The oxidized layer 107 formed by the oxidation (step 208)
includes properties corresponding to the oxidation reagent used and
the operational parameters. In one embodiment, in comparison to the
layer 102, the oxidized layer 107 is over-oxidized and/or has a
contact angle on a Si wafer of about 60.degree. has an increased
amount of N--H, Si--OH, and/or C--OH groups, has fragile scratch
resistance, has increased acid resistance, has increased corrosion
resistance, or a combination thereof.
[0046] The oxidized layer 107 includes various comparative
properties relative to the layer 102, and/or embodiments with the
oxidized layer 107 being formed by different oxidation reagents.
For example, the oxidized layer 107 has decreased chemical
resistance, has decreased scratch resistance, has decreased
hardness, or a combination thereof. In one embodiment, the oxidized
layer 107 is oxidized and/or has a contact angle on a Si wafer of
about 86.6.degree. has decreased friction (for example, in
comparison to embodiments with the oxidizing reagent being zero air
and water), has decreased wear resistance (for example, in
comparison to embodiments with the oxidizing reagent being zero air
and water), includes Si--O--Si groups (for example, capable of
being shown by FT-IR data having a growth of the Si--O--Si peak at
1026.9 cm.sup.-1 compared to the non-water functionalized peak at
995.2 cm.sup.-1), or a combination thereof. In one embodiment, the
oxidized layer 107 is over-oxidized, has a decreased amount of C--H
groups (for example, in comparison to embodiments with the
oxidizing reagent being water alone), has a decreased amount of
Si--C groups (for example, in comparison to embodiments with the
oxidizing reagent being water alone), has an increased amount of
Si--OH/C--OH groups (for example, in comparison to embodiments with
the oxidizing reagent being water alone), or a combination thereof.
In one embodiment, the oxidized layer 107 has lower coefficient of
friction (for example, in comparison to embodiments with the
oxidization agent being zero air and water), has increased wear
resistance (for example, in comparison to embodiments with the
oxidization agent being zero air and water), includes Si--O--Si
groups, or a combination thereof.
[0047] In one embodiment, the coefficient of friction is decreased
by the oxidation (step 208). For example, in an embodiment with the
oxidation (step 208) of the layer 102, the layer 102 includes a
first coefficient of friction (for example, about 0.97) prior to
the oxidation (step 208) and a second coefficient of friction (for
example, about 0.84) after the oxidation (step 208).
[0048] In one embodiment, the wear rate is decreased by the
oxidation (step 208). For example, in an embodiment with the
oxidation (step 208) of the layer 102, the layer 102 includes a
first wear rate (for example, 4.73.times.10.sup.-4 mm.sup.3/N/m)
prior to the oxidation (step 208) and a second wear rate (for
example, about 6.75.times.10.sup.-5 mm.sup.3/N/m) after the
oxidation (step 208).
[0049] In one embodiment including the oxidation (step 208) using
water as the oxidant, the article 103 includes a composition as is
shown in the Auger Electron Spectroscopy plot of FIG. 7 or a
similar variation thereof.
[0050] The post-oxidation functionalization (step 210) is or
includes thermal coupling of one or more materials.
[0051] In one embodiment, the post-oxidation functionalization
(step 210) modifies the oxidized layer 107, for example, by heating
and/or modifying the surface, to form the
oxidized-then-functionalized layer 109 shown in FIGS. 4-5. Heat,
exposure times, diluent gases, and pressures are adjusted to affect
the degree of post-oxidation functionalization (step 210). Control
of this degree of the post-oxidation functionalization (step 210)
imparts predetermined properties. In one embodiment, the oxidized
layer is exposed to an organosilane reagent at a temperature of
about 300.degree. to 600.degree. C., for about 1 to 24 hours and at
a pressure of about 5 to 100 psia, in some cases about 25 psia,
about 27 psia, about 54 psia, or any suitable ranges there between.
In one embodiment, inert diluent gases are used, such as argon or
nitrogen, for example, at partial pressures of about 1 to 100 psia
to assist the reaction.
[0052] In one embodiment, the oxidized-then-functionalized layer
109 has a contact angle for deionized water on a mirror surface of
greater than about 105.degree., greater than about 110.degree.,
greater than about 112.degree., between about 100.degree. and about
114.degree., about 110.3.degree., about 112.1.degree., about
113.7.degree., or any suitable range, sub-range, combination, or
sub-combination thereof. Additionally or alternatively, in one
embodiment, the oxidized-then-functionalized layer 109 has a
contact angle for deionized water on a mirror surface that is less
than polytetrafluoroethylene, for example, by about 1.degree.,
about 2.degree., between about 1.degree. and about 2.degree., or
any suitable range, sub-range, combination, or sub-combination
thereof.
[0053] In one embodiment, the oxidized-then-functionalized layer
109 has a contact angle for deionized water on a rough surface of
greater than about 140.degree., greater than about 145.degree.,
between about 140.degree. and about 150.degree., about
142.7.degree., about 145.7.degree., about 148.1.degree., or any
suitable range, sub-range, combination, or sub-combination thereof.
Additionally or alternatively, in one embodiment, the
oxidized-then-functionalized layer 109 has a contact angle for
deionized water on a rough surface that is greater than
polytetrafluoroethylene, for example, by about 25.degree., about
30.degree., between about 20.degree. and about 35.degree., or any
suitable range, sub-range, combination, or sub-combination
thereof.
[0054] In one embodiment, the oxidized-then-functionalized layer
109 has greater anti-stiction properties than the oxidized layer
107, for example, formed with zero air as the binding reagent. As
such, in one embodiment of the coating process 200, the
oxidized-then-functionalized layer 109 has increased
anti-stiction.
[0055] By modifying and varying the R-groups, or by using other
molecules capable of hydroxyl reactivity, surface properties of the
oxidized-then-functionalized layer 109 are adjusted. For example,
in one embodiment, the adjustments increase or decrease hardness
and anti-stiction, wear resistance, inertness, electrochemical
impedance, contact angle, or a combination thereof, thereby
providing physical performance characteristics expanding the
applicability and durability for use in biomedical and marine
fields.
[0056] The following Examples show various elements relating to the
disclosure. Properties and parameters disclosed within the Examples
should be considered as being disclosed within the Detailed
Description of the Invention, whether comparative in nature or
illustrative in nature.
EXAMPLE 1
[0057] A first example includes performing the process 200 on a
sensor of a Quartz Crystal Microbalance with Dissipation monitoring
(QCM-D) system to form the coating 101. QCM-D is employed as a
highly sensitive mass sensor to detect mass uptake or release on
the ng/cm.sup.2 scale at the sensor surface by interpreting changes
in the quartz resonance frequency. The coating 101 includes
protein-repellant properties formed on the surface of a QCM-D
sensor. The QCM-D sensor is a circular quartz crystal of 14 mm in
diameter and 0.3 mm in thickness. The quartz crystal is coated with
a layer of gold electrode (40-1,000 nm in thickness) on both sides
for electrical contact. On one side of the crystal, the gold is
further coated with medical-grade 316L stainless steel. The process
200 includes the thermal decomposition (step 204) of the
dimethylsilane applying the coating 101 to the QCM-D sensor
substrate for 6 to 15 hours at 10 to 30 psia gas at 450.degree. C.
to form the layer 102.
[0058] The layer 102 is then oxidized (step 208) with zero air for
2 hours at about 1 to 200 psia gas at a temperature between
250-500.degree. C. to form the oxidized layer 107. The process 200
then includes post-oxidation functionalization (step 210) of the
oxidized layer 107 by introducing trimethylsilane to an evacuated
chamber including the oxidized layer 107 at 400-500.degree. C. and
25 psia and reacted for 5-10 hours to form the coating 101.
[0059] Contact angle is measured to be 92.3.degree. on the coated
stainless steel surface showing hydrophobic property. The coating
thickness is measured to be 250 nm.
EXAMPLE 2
[0060] The second example includes performing the process 200 as
described in Example 1 on the exterior and interior surfaces of a
medical-grade 316L stainless steel probe, capable of use in an in
vitro medical diagnostic system. The probe has an internal diameter
in the range of 1 mm to 3 mm. The process 200 forms the coating 101
on the exterior and the interior surfaces of the probe.
[0061] Contact angle is measured to be 92.3.degree. on the coated
stainless steel surface showing hydrophobic property. The coating
thickness is measured to be about 27 nm in the interior
surface.
EXAMPLE 3
[0062] The third example includes performing the process 200 as
described in Example 1 on a rectangular panel of 316L stainless
steel having a size of 4 inches by 8 inches (10.2.times.20.3 cm)
and 0.6 cm in thickness. Holes having a 1.3 cm diameter are drilled
2 cm from the sides of each corner of the panel. The coating 101 is
formed by the process 200 on all surfaces of the panel. The coating
101 is then exposed to biofouling in a seawater environment to
ascertain the relative antifouling performance compared to
reference surfaces. Results show that the coating 101 includes
resistance to biofouling that is greater than coatings failing to
include one or more of the features described herein.
[0063] Contact angle is measured to be 92.3.degree. on the coated
stainless steel surface showing hydrophobic property. The coating
thickness is measured to be about 1,000 nm.
[0064] While only certain features and embodiments of the invention
have been shown and described, many modifications and changes may
occur to those skilled in the art (for example, variations in
sizes, dimensions, structures, shapes and proportions of the
various elements, values of parameters (for example, temperatures,
pressures, etc.), mounting arrangements, use of materials, colors,
orientations, etc.) without materially departing from the novel
teachings and advantages of the subject matter recited in the
claims. The order or sequence of any process or method steps may be
varied or re-sequenced according to alternative embodiments. It is,
therefore, to be understood that the appended claims are intended
to cover all such modifications and changes as fall within the true
spirit of the invention. Furthermore, in an effort to provide a
concise description of the embodiments, all features of an actual
implementation may not have been described (i.e., those unrelated
to the presently contemplated best mode of carrying out the
invention, or those unrelated to enabling the claimed invention).
It should be appreciated that in the development of any such actual
implementation, as in any engineering or design project, numerous
implementation specific decisions may be made. Such a development
effort might be complex and time consuming, but would nevertheless
be a routine undertaking of design, fabrication, and manufacture
for those of ordinary skill having the benefit of this disclosure,
without undue experimentation.
* * * * *