Heterogenous integration for RF, microwave and MM wave systems in photoactive glass substrates
11594457 · 2023-02-28
Assignee
Inventors
Cpc classification
H01L2924/19105
ELECTRICITY
H01L2224/11312
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L23/4824
ELECTRICITY
H01L2224/131
ELECTRICITY
H01L2224/97
ELECTRICITY
H01L2223/6655
ELECTRICITY
H01L24/97
ELECTRICITY
H01L2223/6683
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L23/051
ELECTRICITY
H01L23/498
ELECTRICITY
H01L2924/13064
ELECTRICITY
H01L2224/83132
ELECTRICITY
H01L2223/6672
ELECTRICITY
H01L2224/92242
ELECTRICITY
H01L2224/131
ELECTRICITY
H01L2224/16235
ELECTRICITY
H01L2224/97
ELECTRICITY
H01L2223/6677
ELECTRICITY
H01L2224/4847
ELECTRICITY
H01L24/73
ELECTRICITY
H01L23/544
ELECTRICITY
International classification
H01L23/051
ELECTRICITY
H01L21/48
ELECTRICITY
H01L23/544
ELECTRICITY
Abstract
The present invention includes a method for creating a system in a package with integrated lumped element devices and active devices on a single chip/substrate for heterogeneous integration system-on-chip (HiSoC) in photo-definable glass, comprising: masking a design layout comprising one or more electrical passive and active components on or in a photosensitive glass substrate; activating the photosensitive glass substrate, heating and cooling to make the crystalline material to form a glass-crystalline substrate; etching the glass-crystalline substrate; and depositing, growing, or selectively etching a seed layer on a surface of the glass-crystalline substrate on the surface of the photodefinable glass.
Claims
1. A method for creating a system in a package (SiP) with integrated lumped element devices formed as a heterogeneous integration system-on-chip (HiSoC) comprising the steps of: forming a spacer by: exposing at least one portion of a photosensitive glass substrate with an activating energy source; heating the photosensitive glass substrate above a glass transition temperature thereof for at least ten minutes; cooling the photosensitive glass substrate to transform at least a part of an exposed glass to a crystalline material to form a glass-crystalline substrate; etching the glass-crystalline substrate with an etchant solution to form one or more channels or vias in the glass-crystalline substrate; depositing a seed layer on a surface of the glass-crystalline substrate exposed during the etching step to enable electroplating of copper to fill the one or more channels or vias; and connecting a high electron mobility transistor (HEMT) to a copper plate or copper ground plate via the spacer.
2. The method of claim 1, further comprising masking the copper plate or copper ground plate to produce a design layout comprising one or more rectangular structures with a global alignment mark and a local alignment mark within the design layout.
3. The method of claim 1, further comprising at least one of: forming an isolator with the integrated lump element devices in the SiP; forming a circulator with the integrated lump element devices in the SiP; forming an RF filter with the integrated lump element devices in the SiP; forming at least one of a low pass, high pass filter, notch filter, band pass filter, transformer, circulator, coupler, isolator, with the integrated lump element devices in the SiP; forming a power combiner, a power splitter RF Circuit in or on the photosensitive glass substrate; or forming one or more RF Filters, RF Circulators, RF Isolators, Antenna, Impedance Matching Elements, 50 Ohm Termination Elements, Integrated Ground Planes, RF Shielding Elements, EMI Shielding Elements, RF Combiners, RF Splitters, Transformers, Switches, power splitters, power combiners, Duplexer, or Diplexers in or on the photosensitive glass substrate.
4. The method of claim 1, further comprising forming a SiP RF Circuit that eliminates at least 30% or 35% of an RF parasitic signal associated with mounting the package with lumped element devices to a substrate.
5. The method of claim 1, wherein the HiSoC comprises one or more layers.
6. A package lumped element device mounted to a system-in-package (SiP) in or on photo-definable glass made by a method comprising: forming a spacer by: exposing at least one portion of a photosensitive glass substrate with an activating energy source; heating the photosensitive glass substrate above a glass transition temperature thereof for at least ten minutes; cooling the photosensitive glass substrate to transform at least a part of an exposed glass of the photosensitive glass substrate to a crystalline material to form a glass-crystalline substrate; etching the glass-crystalline substrate with an etchant solution to form one or more channels or vias in the glass-crystalline substrate; depositing a seed layer on a surface of the glass-crystalline substrate exposed during the etching step to enable electroplating of copper to fill the one or more channels or vias; and connecting a high electron mobility transistor (HEMT) to a copper plate or copper ground plate via the spacer.
7. The device of claim 6, wherein the package lumped element device is at least one of an isolator with the integrated lump element devices in the SiP; a circulator with the integrated lump element devices in the SiP; an RF filter with the integrated lump element devices in the SiP; at least one of a low pass, high pass filter, notch filter, band pass filter, transformer, circulator, coupler, isolator, with integrated lump element devices in the SiP; a power combiner, a power splitter RF Circuit in or on the photo-definable glass substrate; a SiP RF Circuit that eliminates at least 15% of an RF parasitic signal associated with the packaging a mount elements to the photosensitive glass substrate; a SiP RF Circuit that eliminates at least 25% of the RF parasitic signal associated with mounting the package lumped element device to a substrate; or one or more RF Filters, RF Circulators, RF Isolators, Antenna, Impedance Matching Elements, 50 Ohm Termination Elements, Integrated Ground Planes, RF Shielding Elements, EMI Shielding Elements, RF Combiners, RF Splitters, Transformers, Switches, power splitters, power combiners, Duplexers, or Diplexers.
8. A method for creating a system in a package with integrated lumped element devices formed as a system-in-package (SiP) in or on the photosensitive glass substrate comprising the steps of: masking a design layout comprising one or more structures to form one or more electrical components on or in a photosensitive glass substrate spacer; transforming at least a part of an exposed glass of the photosensitive glass substrate spacer to a crystalline material to form a glass-crystalline substrate; etching the glass-crystalline substrate with an etchant solution to form one or more channels or vias in the glass-crystalline substrate; depositing a seed layer on a surface of the glass-crystalline substrate exposed during the etching step to enable electroplating of copper to fill the one or more channels or vias and deposit on the surface of the photosensitive glass substrate spacer; and placing and electrically connecting a high electron mobility transistor (HEMT) on a copper plate or copper-coated glass wafer across the photosensitive glass substrate spacer.
9. The method of claim 8, wherein the SiP is a heterogeneous integration system-on-chip HiSoC that reduces the parasitic noise and losses at least 30, 35, 40, 45, 50, or 60% when compared to an equivalent surface mounted device.
10. The method of claim 8, further comprising forming at least one of: an isolator with the integrated lump element devices in the SiP; a circulator with the integrated lump element devices in the SiP; an RF filter with the integrated lump element devices in the SiP; at least one of a low pass, high pass filter, notch filter, band pass filter, transformer, circulator, coupler, isolator, with integrated lump element devices in a SiP; a power combiner, a power splitter RF Circuit in or on the photo-definable glass substrate.
11. The method of claim 8, further comprising forming an SiP RF Circuit that eliminates at least 25, 30 or 30% of an RF parasitic signal associated with mounting the package with integrated lumped element devices to a substrate.
12. The method of claim 8, further comprising forming one or more RF Filters, RF Circulators, RF Isolators, Antenna, Impedance Matching Elements, 50 Ohm Termination Elements, Integrated Ground Planes, RF Shielding Elements, EMI Shielding Elements, RF Combiners, RF Splitters, Transformers, Switches, power splitters, power combiners, Duplexers, and/or Diplexers.
13. A method for creating a system in a package with integrated lumped element devices formed as a heterogeneous integration system-on-chip (HiSoC) using a photo-definable glass comprising the steps of: forming an integrated passive device (IPD) wafer by: obtaining a copper plate or substrate; coating the copper plate or substrate with a photoresist in an alignment pattern for one or more dies; using the alignment pattern to pick, place and bond an active device to the copper plate or substrate; depositing solder bonding balls on one or more contact pads of the active device; forming a spacer wafer by: lapping and polishing a spacer wafer of the photo-definable glass; exposing, baking and etching one or more through hole openings or through hole vias to provide an electrical connection through the spacer wafer; depositing a seed layer of Ti/Cu by chemical vapor deposition (CVD) on the spacer wafer; electroplating or electroless plating copper into the one or more through hole openings or through hole vias in the spacer wafer; removing excess copper to reduce a thickness of the copper on the spacer wafer; coating, exposing and developing a photoresist in a pattern on a first side of the spacer wafer, wherein the pattern has a spacer edge area that is smaller than the pattern on the spacer wafer; coating the first side of the spacer wafer with an electrically conductive material with a sputter deposition system; removing the photoresist to leave the electrically conductive material in a continuous pattern; uniformly coating a second side of the spacer wafer with an electrically conductive material using the sputter deposition system; aligning the spacer wafer on the copper plate or substrate with the alignment pattern; bonding the spacer wafer and to the copper plate or substrate; depositing one or more solder balls on an opposite side of the spacer wafer at the one or more through hole openings or through hole vias; and using the alignment pattern to electrically connect the integrated passive device (IPD) wafer to the spacer wafer with the one or more solder balls to connect the active device to a ground.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures and in which:
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DETAILED DESCRIPTION OF THE INVENTION
(13) While the production and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.
(14) To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as “a”, “an” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not limit the invention, except as outlined in the claims.
(15) The present invention eliminates the parasitic losses and signals associated with lumped element devices in the RF domain. Lumped element devices or an array of lumped element devices consist of capacitors, inductors, and resistors to implement a wide number of electronic devices and functions including: filters (band-pass, band-stop, high-pass, notch, low-pass filter), circulators, antenna, power conditioning, coupler, power combiner, power splitter, matching networks, isolators and/or Doherty power amplifier in photo definable glass ceramic heterogeneous integration system on a Chip (HiSoC) maximizing packing density while eliminates or greatly reduce parasitic signals, losses while enhancing electrical efficiency. The parasitic signals or losses are generated from antennas/wire bonds effects combined with the inductance, capacitance and resistance from the packaging, solder bonding (ball grid), electronic connectors (wire), electrical bond pads and mounting elements that attach the packaged passive and active devices to form a HiSoC.
(16) To address these needs, the present inventors developed a glass ceramic (APEX® Glass ceramic) as a novel packaging and substrate material for semiconductors, RF electronics, microwave electronics, and optical imaging. APEX® Glass ceramic is processed using first generation semiconductor equipment in a simple three step process and the final material can be fashioned into either glass, ceramic, or contain regions of both glass and ceramic. The APEX® Glass ceramic enables the creation of an HiSoC that includes one or part of the following: easily fabricated high density vias, electronic devices including; Inductors, Capacitors, Resistors, Transmission Lines, Coax Lines, Antenna, Microprocessor, Memory, Amplifier, Transistors, matching networks, RF Filters, RF Circulators, RF Isolators, Impedance Matching Elements, 50 Ohm Termination Elements, Integrated Ground Planes, RF Shielding Elements, EMI Shielding Elements, RF Combiners, RF Couplers, RF Splitters, Transformers, Transistors, Gain circuits, Switches, Multiplexors, Duplexers, and/or Diplexers.
(17) The present inventors have demonstrated wafer-level processing of 65-μm diameter, 72-μm pitch non-copper filled TGV arrays on full 4″ wafers. Calculations show that a 50-μm diameter/70-μm pitch TGV array (40% copper density in glass). This can be seen in
(18) A major challenge in the realization of high RF performance interconnects technology today is maintaining the appropriate characteristic impedance across the vertical layer-to-layer interface. To overcome these limitations, the present inventors explored several architectures that focus on shielded interconnects. An example of these interconnects is shown in
(19) An HiSoC with a fully integrated lumped element device can be produced in a photo-definable glasses have high temperature stability, good mechanical and electrical properties, and have better chemical resistance than plastics and many metals. To our knowledge, the only commercial photo-definable glass is FOTURAN™, made by Schott Corporation. FOTURAN™ comprises a lithium-aluminum-silicate glass containing traces of silver ions. When exposed to UV-light within the absorption band of cerium oxide the cerium oxide acts as sensitizers, absorbing a photon and losing an electron that reduces neighboring silver oxide to form silver atoms, e.g.,
Ce.sup.3++Ag.sup.+=Ce.sup.4++Ag.sup.0
(20) The silver atoms coalesce into silver nanoclusters during the baking process and induces nucleation sites for crystallization of the surrounding glass. If not processed properly or if the composition of photodefinable glass is wrong the coalesce of the silver ions can cause a uncontrolled mechanical distortion of up to 500 μm in the x/y plane of the as has been reported in FOTURAN™ photodefinable glass making layer-to-layer wafer-to-wafer alignment and assembly impossible. Only the UV light exposed regions of the glass will crystallize during subsequent heat treatment.
(21) This heat treatment must be performed at a temperature near the glass transformation temperature (e.g., greater than 465° C. in air for FOTURAN®). The crystalline phase is more soluble in etchants, such as hydrofluoric acid (HF), than the unexposed vitreous, amorphous regions. In particular, the crystalline regions of FOTURAN® are etched about 20 times faster than the amorphous regions in 10% HF, enabling microstructures with wall slopes ratios of about 20:1 when the exposed regions are removed. See T. R. Dietrich et al., “Fabrication technologies for microsystems utilizing photoetchable glass,” Microelectronic Engineering 30, 497 (1996), which is incorporated herein by reference.
(22) Preferably, the shaped glass structure contains at least one or more, two or three-dimensional inductive device. The inductive device is formed by making a series of connected loops to form a free-standing inductor. The loops can be rectangular, circular, elliptical, fractal or other shapes that create and pattern that generates induction. The patterned regions of the APEX® glass can be filled with metal, alloys, composites, glass or other magnetic media, by a number of methods including plating or vapor phase deposition. The magnetic permittivity of the media combined with the dimensions and number of structures (loops, turns or other inductive element) in the device provide the inductance of devices.
(23) FOTURAN® is composed of silicon oxide (SiO.sub.2) of 75-85% by weight, lithium oxide (Li.sub.2O) of 7-11% by weight, aluminum oxide (Al.sub.2O.sub.3) of 3-6% by weight, sodium oxide (Na.sub.2O) of 1-2% by weight, 0.2-0.5% by weight antimonium trioxide (Sb.sub.2O.sub.3) or arsenic oxide (As.sub.2O.sub.3), silver oxide (Ag.sub.2O) of 0.05-0.15% by weight, and cerium oxide (CeO.sub.2) of 0.01-0.04% by weight. As used herein the terms “APEX® Glass ceramic”, “APEX® glass” or simply “APEX®” is used to denote one embodiment of the glass ceramic composition of the present invention.
(24) The present invention provides a single material approach for the fabrication of optical microstructures with photo-definable APEX glass for use in imaging applications by the shaped APEX glass structures that are used for lenses and includes through-layer or in-layer designs.
(25) Generally, glass ceramics materials have had limited success in microstructure formation plagued by performance, uniformity, usability by others and availability issues. Past glass-ceramic materials have yield etch aspect-ratio of approximately 15:1 in contrast APEX® glass has an average etch aspect ratio greater than 50:1. This allows users to create smaller and deeper features. Additionally, our manufacturing process enables product yields of greater than 90% (legacy glass yields are closer to 50%). Lastly, in legacy glass ceramics, approximately only 30% of the glass is converted into the ceramic state, whereas with APEX® Glass ceramic this conversion is closer to 70%.
(26) The APEX® Glass composition provides three main mechanisms for its enhanced performance: (1) The higher amount of silver leads to the formation of smaller ceramic crystals which are etched faster at the grain boundaries, (2) the decrease in silica content (the main constituent etched by the HF acid) decreases the undesired etching of unexposed material, and (3) the higher total weight percent of the alkali metals and boron oxide produces a much more homogeneous glass during manufacturing.
(27) The present invention includes a method for fabricating a glass ceramic structure for use in forming inductive structures used in electromagnetic transmission, transformers and filtering applications. The present invention includes an inductive structure created in the multiple planes of a glass-ceramic substrate, such process employing the (a) exposure to excitation energy such that the exposure occurs at various angles by either altering the orientation of the substrate or of the energy source, (b) a bake step and (c) an etch step. Angle sizes can be either acute or obtuse. The curved and digital structures are difficult, if not infeasible to create in most glass, ceramic or silicon substrates. The present invention has created the capability to create such structures in both the vertical as well as horizontal plane for glass-ceramic substrates. The present invention includes a method for fabricating of an inductive structure on or in a glass ceramic.
(28) Ceramicization of the glass is accomplished by exposing the entire glass substrate to approximately 20 J/cm.sup.2 of 310 nm light. When trying to create glass spaces within the ceramic, users expose all of the material, except where the glass is to remain glass. In one embodiment, the present invention provides a quartz/chrome mask containing a variety of concentric circles with different diameters.
(29) The present invention includes a method for fabricating an inductive device in or on glass ceramic structure electrical microwave and radio frequency applications. The glass ceramic substrate may be a photosensitive glass substrate having a wide number of compositional variations including but not limited to: 60-76 weight % silica; at least 3 weight % K.sub.2O with 6 weight %-16 weight % of a combination of K.sub.2O and Na.sub.2O; 0.003-1 weight % of at least one oxide selected from the group consisting of Ag.sub.2O and Au.sub.2O; 0.003-2 weight % Cu.sub.2O; 0.75 weight %-7 weight % B.sub.2O.sub.3, and 6-7 weight % Al.sub.2O.sub.3; with the combination of B.sub.2O.sub.3; and Al.sub.2O.sub.3 not exceeding 13 weight %; 8-15 weight % Li.sub.2O; and 0.001-0.1 weight % CeO.sub.2. This and other varied composition are generally referred to as the APEX® glass.
(30) The exposed portion may be transformed into a crystalline material by heating the glass substrate to a temperature near the glass transformation temperature. When etching the glass substrate in an etchant such as hydrofluoric acid, the anisotropic-etch ratio of the exposed portion to the unexposed portion is at least 30:1 when the glass is exposed to a broad spectrum mid-ultraviolet (about 308-312 nm) flood lamp to provide a shaped glass structure that have an aspect ratio of at least 30:1, and to create an inductive structure. The mask for the exposure can be of a halftone mask that provides a continuous grey scale to the exposure to form a curved structure for the creation an inductive structure/device. A halftone mask or grey scale enables the control the device structure by controlling the exposure intensity undercut of a digital mask can also be used with the flood exposure can be used to produce for the creation an inductive structure/device. The exposed glass is then typically baked in a two-step process. Temperature range heated between of 420° C.-520° C. for between 10 minutes to 2 hours, for the coalescing of silver ions into silver nanoparticles and temperature range heated between 520° C.-620° C. for between 10 minutes and 2 hours allowing the lithium oxide to form around the silver nanoparticles. The glass plate is then etched. The glass substrate is etched in an etchant, of HF solution, typically 5% to 10% by volume, wherein the etch ratio of exposed portion to that of the unexposed portion is at least 30:1 when exposed with a broad spectrum mid-ultraviolet flood light, and greater than 30:1 when exposed with a laser, to provide a shaped glass structure with an anisotropic-etch. The glass substrate is then etched in an etchant, of HF solution, typically 5% to 10% by volume.
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(33) In certain examples, a resistor section of HiSoC and its manufacture is shown. On a surface of the photodefinable glass wafer from Step 2, a photomask is deposited on the photodefinable glass with the pattern of a via is formed, and the photodefinable glass is exposed to a radiation at 310 nm with an intensity ˜20 J/cm.sup.2 and baked to create the exposure as described above. The width, length and depth of the exposure combined with the resistivity of the resistor media, which determines the resistor value. Both a top view of a cross-sectional side view are shown including a via pattern for the resistor is shown. Exposure of the photodefinable glass not covered by the mask creates a ceramic in the photodefinable glass.
(34) The etched regions of the photodefinable glass are filled with a RF resistor paste or media of Alumina, AlN, Be or other high frequency resistor material. The trench is filed resistor paste or media is deposited via a silk-screening process. Excess paste is removed by a light DI water or IPA rinse and nylon wipe.
(35) The photodefinable glass wafer with the resistor paste is then placed into an annealing oven with an inert environment such as Argon or a vacuum. The photodefinable glass wafer is ramped to sinter the resistive material. Any excess resistor media on the surface can be removed by a 5 min CMP process with 2 μm Silica polishing media and water.
(36) To connect the resistor, the photodefinable glass is again coated with a standard photoresist. A pattern is exposed and developed following the standard process to create a pattern through the photoresists that a resistor layer can be deposited. The wafer is exposed to a light O.sub.2 plasma to remove any residual organic material in the pattern. Typically this is accomplished at 0.1 m Torr with 200 W forward power for 1 min. Next, a metallization layer is deposited, e.g., a thin film of tantalum, titanium TiN, TiW, NiCr or other similar media. Typically, the deposition is accomplished by a vacuum deposition. The vacuum deposition of a seed layer can be accomplished by DC sputtering of tantalum through a liftoff pattern on to the glass substrate at a rate of 40 Å/min.
(37) In another method, the photodefinable glass wafer is coated with a standard photoresist. A pattern is exposed and developed following the standard process to create a pattern through the photoresists that a metallic seed layer can be deposited. The wafer is exposed to a light O.sub.2 plasma to remove any residual organic material in the pattern. Typically, this is accomplished at 0.1 mTorr with 200 W forward power for 1 min. A thin film seed layer of 400 Å of tantalum is deposited by a vacuum deposition. The vacuum deposition of a seed layer can be accomplished by DC sputtering of tantalum through a liftoff pattern on to the glass substrate at a rate of 40 Å/min.
(38) In another embodiment, shown in
(39) In another embodiment, shown in
(40) The glass regions that have been converted to ceramic are etched in a wet etch of HF acid as described above. The photodefinable glass 10 wafer is the placed in a copper plating bath that preferentially plates the etched ceramic structure and completely fills the via and interdigitated line structure as described above.
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(42) TABLE-US-00001 TABLE 1 Table of compatibility elements for different substrates used for RF, microwave and millimeter wave applications. Rogers 4003 PCB DuPont LTCC Characteristic 3D Glass [1] [2] Silicon Flexible heterogeneous ✓✓✓✓ ✓ ✓ ✓ integration Dielectric constant 1.5-6.5 3.55 5.8 11.7 Tanδ 0.0008-0.008 .0027 .014 .005 Young's modulus (GPa) 86 25 120 185 CTE (ppm/K) 10 11-46 5.8 3.0 Thermal conductivity 154 0.71 3.3 135 Quick design/ 1 week 1 week 4 weeks >4 weeks manufacturing Fine pitch metal >2 >100 >100 >1 (microns) Through vias for I/Os >10 >100 >100 >1 (microns) 3D structuring w/micron ✓✓✓✓ ✓ ✓ ✓✓✓✓ precision
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(46) It is contemplated that any embodiment discussed in this specification can be implemented with respect to any method, kit, reagent, or composition of the invention, and vice versa. Furthermore, compositions of the invention can be used to achieve methods of the invention.
(47) It will be understood that particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention can be employed in various embodiments without departing from the scope of the invention. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.
(48) Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. In some cases, where the desired circuit performance or material compatibility the HiSoC may choose to use a SMD version of a resistor, capacitor, or inductor, in lieu of one of the photo-definable glass based devices. Using an SMD version of one or more of the elements will contribute to the parasitic generated noise of the HiSoC requiring extra care in the assembly and packaging. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
(49) All publications and patent applications mentioned in the specification are indicative of the level of skill of those skilled in the art to which this invention pertains. All publications and patent applications are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.
(50) The use of the word “a” or “an” when used in conjunction with the term “comprising” in the claims and/or the specification may mean “one,” but it is also consistent with the meaning of “one or more,” “at least one,” and “one or more than one.” The use of the term “or” in the claims is used to mean “and/or” unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive, although the disclosure supports a definition that refers to only alternatives and “and/or.” Throughout this application, the term “about” is used to indicate that a value includes the inherent variation of error for the device, the method being employed to determine the value, or the variation that exists among the study subjects.
(51) As used in this specification and claim(s), the words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “includes” and “include”) or “containing” (and any form of containing, such as “contains” and “contain”) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps. In embodiments of any of the compositions and methods provided herein, “comprising” may be replaced with “consisting essentially of” or “consisting of”. As used herein, the phrase “consisting essentially of” requires the specified integer(s) or steps as well as those that do not materially affect the character or function of the claimed invention. As used herein, the term “consisting” is used to indicate the presence of the recited integer (e.g., a feature, an element, a characteristic, a property, a method/process step or a limitation) or group of integers (e.g., feature(s), element(s), characteristic(s), property(ies), method/process steps or limitation(s)) only.
(52) The term “or combinations thereof” as used herein refers to all permutations and combinations of the listed items preceding the term. For example, “A, B, C, or combinations thereof” is intended to include at least one of: A, B, C, AB, AC, BC, or ABC, and if order is important in a particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB. Continuing with this example, expressly included are combinations that contain repeats of one or more item or term, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, and so forth. The skilled artisan will understand that typically there is no limit on the number of items or terms in any combination, unless otherwise apparent from the context.
(53) As used herein, words of approximation such as, without limitation, “about”, “substantial” or “substantially” refers to a condition that when so modified is understood to not necessarily be absolute or perfect but would be considered close enough to those of ordinary skill in the art to warrant designating the condition as being present. The extent to which the description may vary will depend on how great a change can be instituted and still have one of ordinary skilled in the art recognize the modified feature as still having the required characteristics and capabilities of the unmodified feature. In general, but subject to the preceding discussion, a numerical value herein that is modified by a word of approximation such as “about” may vary from the stated value by at least ±1, 2, 3, 4, 5, 6, 7, 10, 12 or 15%.
(54) All of the compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims.