- Temple University
Department of Chemistry
Philadelphia PA 19122 USA
Barry Arkles
Temple University, Chemistry, Faculty Member
- Polymer Chemistry, Silicon, Hydrophobicity, Thin film technology for electrical and electronic applications, Microfluidics, Silicones Chemistry, and 10 moreSilicon Chemistry, Elastomers, Siloxane and Silicone Polymers, Organometallic Chemistry, Sol-Gel Technology, Fluoropolymers, Thin Films and Coatings, Organosilicon Compounds, Polymer Composites, and Advanced Ceramicsedit
Silicon carbide (SiC x) thin films deposition processes fall primarily into three main categories: (1) chemical vapor deposition (CVD) and its variants, including plasma enhanced CVD (PE-CVD); (2) physical vapor deposition (PVD),... more
Silicon carbide (SiC x) thin films deposition processes fall primarily into three main categories: (1) chemical vapor deposition (CVD) and its variants, including plasma enhanced CVD (PE-CVD); (2) physical vapor deposition (PVD), including various forms of sputtering; (3) alternative (non-CVD and non-PVD) methodologies. Part I of this two-part report ECS J. Solid State Sci. Technol., 12, 103001 (2023) examined recent peer-reviewed publications available in the public domain pertaining to the various CVD processes for SiC x thin films and nanostructures, as well as CVD modeling and mechanistic studies. In Part II, we continue our detailed, systematic review of the latest progress in cutting-edge SiC x thin film innovations, focusing on PVD and other non-PVD and non-CVD SiC x coating technologies. Particular attention is given to pertinent experimental details from PVD and alternative (non-CVD and non-PVD) processing methodologies as well as their influence on resulting film properties and performance. keywords physical vapor deposition; silicon carbide
Research Interests:
To provide an integrated system for synthesis of a film-forming precursor, consumption of the precursor and formation of a thin film on a substrate.SOLUTION: The integrated system includes a raw material source, a precursor synthesis... more
To provide an integrated system for synthesis of a film-forming precursor, consumption of the precursor and formation of a thin film on a substrate.SOLUTION: The integrated system includes a raw material source, a precursor synthesis chamber in communication with the raw material source, a thin film processing chamber in communication with the precursor synthesis chamber for supplying the precursor from the precursor synthesis chamber to the thin film processing chamber in a controlled manner for consumption of the precursor to form the thin film on the substrate, a monitoring system for monitoring of the thin film formation in the thin film processing chamber and/or the precursor synthesis in the precursor synthesis chamber, and a controller for controlling a rate of the precursor synthesis, precursor consumption and/or thin film formation. The rate of precursor synthesis is synchronized with the rate of precursor consumption for formation of the thin film.
Research Interests:
In Part I of a two-part report, we provide a detailed and systematic review of the latest progress in cutting-edge innovations for the silicon carbide (SiC) material system, focusing on chemical vapor deposition (CVD) thin film... more
In Part I of a two-part report, we provide a detailed and systematic review of the latest progress in cutting-edge innovations for the silicon carbide (SiC) material system, focusing on chemical vapor deposition (CVD) thin film technologies. To this end, up-to-date results from both incremental developments in traditional SiC applications as well major advances in novel SiC usages are summarized. Emphasis is placed on new chemical sources for Si and C, particularly in the form of single source SiC precursors as well as emerging molecular and atomic scale deposition techniques, with special attention to their effects on resulting film properties and performance. The review also covers relevant research and development efforts as well as their potential impact on and role in the introduction of new technological applications. Part II will focus on findings for physical vapor deposition (PVD) as well as other deposition techniques.
Research Interests: Materials Science, Thin Films and Coatings, Thin film technology for electrical and electronic applications, Chemical Vapor Deposition, Semiconductor Materials, and 10 moreSilicon Carbide, Plasma Enhanced Chemical vapour deposition (PECVD), SIC, Refractory Materials, PVD, CVD, ALD, Organosilicon Compounds, Silicon Carbide Power Devices, Solid State Physics- Thin films for Optoelectronic Applications, Precursor Chemistry, and Implantable Electronics
A method for producing a contact lens having a water contact angle below about 90° involves preparing a molding resin comprising a polyether modified polyolefin; forming the molding resin into a mold; preparing a contact lens composition;... more
A method for producing a contact lens having a water contact angle below about 90° involves preparing a molding resin comprising a polyether modified polyolefin; forming the molding resin into a mold; preparing a contact lens composition; filling the contact lens composition into the mold; and polymerizing the contact lens composition to form a contact lens. A method of inducing water contact angle below 90° and improved surface wettability of a contact lens involves cast polymerizing a mixture of monomers in a mold formed from a molding resin containing a polyether modified polyolefin to form a contact lens having a water contact angle of less than about 90°. Single-use molds for contact lens manufacture are also provided.
Research Interests: Hydrogels, Contact Lenses, Medical devices, Silicone Hydrogel Contact Lens, PEGylation, and 12 moreReactive extrusion, polymer science and Engineering, Surface grafting, modification and characterization of polymeric materials, Surface Properties, Synthesis of Grafted Polymer, Organosilicon Compounds, Biocompatible Materials, Acrylic Resins/chemistry, Post Reactor Modification of Polyolefin, Hydrophilic and hydrophobic polymers, Macromers, and polypropylene grafted maleic anhydride
A method for deposition of a cobalt thin film onto a substrate is provided. The method includes providing a source precursor containing on or more of elements constituting the thin film generating a transient species from the source... more
A method for deposition of a cobalt thin film onto a substrate is provided. The method includes providing a source precursor containing on or more of elements constituting the thin film generating a transient species from the source precursor and depositing a thin film onto the substrate from the transient species. The transient species being a reactive intermediate that has a limited lifetime in a condensed phase at room temperature.
Research Interests:
Large ring silacrown ethers having at least fourteen ring atoms with at least one lipophilic or hydrophobic substituent on the ring and/or on the silicon atom are provided. Pharmaceutical compositions containing these silacrown ethers and... more
Large ring silacrown ethers having at least fourteen ring atoms with at least one lipophilic or hydrophobic substituent on the ring and/or on the silicon atom are provided. Pharmaceutical compositions containing these silacrown ethers and the use of these materials as therapeutic agents are also described. Keywords: Ion Channel; channelopathy; macrocycle; ionophore; crown ether; vasodilator; heterocyclic chemistry
Research Interests:
A method for forming a fluorinated oxostannate film involves vaporizing a volatile fluorinated alkyltin compound having at least two hydrolytically sensitive functional groups or at least two reactive functional groups which are sensitive... more
A method for forming a fluorinated oxostannate film involves vaporizing a volatile fluorinated alkyltin compound having at least two hydrolytically sensitive functional groups or at least two reactive functional groups which are sensitive to oxidation at a temperature greater than 200° C.; providing a substrate; physisorbing or chemisorbing the fluorinated alkyltin compound onto the substrate; and exposing the physisorbed or chemisorbed fluorinated alkyltin compound to a sequence of hydrolysis, irradiation, and/or oxidation steps to form the fluorinated oxostannate thin film on the substrate. Fluorinated alkyltin compounds having formula (I) are also described, in which Rf is a fluorinated or partially fluorinated linear or branched alkyl group having about 1 to about 5 carbon atoms, X is a dialkylamino group having about 1 to about 4 carbon atoms, and n is 1 or 2: (RfCH2)nSnX(4-n) (I).
Research Interests: Inorganic Chemistry, Thin Films and Coatings, Organometallic Chemistry, Transparent Conducting Oxide Materials, Chemical Vapor Deposition, and 7 moreOrganotin, Organotin Compounds, Extreme Ultraviolet Lithography, EUV Lithography, Semiconductor Fabrication Processes and Devices, Tin Chemistry, and Metal Organic Chemical Vapor Deposition
Silicon nitride (SiN x , x ∼ 1) thin films were deposited by chemical vapor deposition on silicon oxide (SiO 2) substrates by combining controlled pulses of the precursor 1,3,5-tri(isopropyl)cyclotrisilazane (TICZ, C 9 H 27 N 3 Si 3) with... more
Silicon nitride (SiN x , x ∼ 1) thin films were deposited by chemical vapor deposition on silicon oxide (SiO 2) substrates by combining controlled pulses of the precursor 1,3,5-tri(isopropyl)cyclotrisilazane (TICZ, C 9 H 27 N 3 Si 3) with a continuous ammonia (NH 3) plasma. This plasma-assisted pulsed CVD (PPCVD) process enables the integration of the nanoscale thickness and uniformity control achieved in atomic layer deposition with the efficiency of plasma-enhanced CVD (PE-CVD). TICZ was selected because it is a nonpyrophoric stable liquid with a high vapor pressure (∼133 Pa at 70°C) and could act as a single source for SiN x with both high Si and N contents. An optimized PPCVD process window was identified consisting of a substrate temperature of 350°C, a TICZ pulse of ≤0.2 s, and a TICZ purge pulse ≥10 s in a continuous direct NH 3 plasma at a NH 3 flow rate and a power of 40 SCCM and 3000 W, respectively. The as-deposited films were analyzed by x-ray photoelectron spectroscopy (XPS) and spectroscopic ellipsometry. XPS analysis confirmed the absence of any C inclusion and demonstrated the existence of the 1:1 Si:N ratio. In situ, real-time ellipsometry measurements indicated that SiN x growth occurred in a typical PE-CVD regime. They also yielded an as-grown SiN x average refractive index of ∼1.75.
Research Interests:
Contact lenses are one of the most successful biomaterials in history with a global market estimated to be worth over $17 billion in 2025. Silicone hydrogel contact lenses dominate the market and are complex biphasic biomaterials with... more
Contact lenses are one of the most successful biomaterials in history with a global market estimated to be worth over $17 billion in 2025. Silicone hydrogel contact lenses dominate the market and are complex biphasic biomaterials with several critical material properties needed for clinical use. Careful consideration of composition and chemistry is needed to identify formulations of lenses meeting all commercial standards with the potential for improved manufacturability, cost, and/or next generation use. Four silicone macromers were investigated in this work with varying symmetry of siloxane units and macromer structure, number of siloxane groups, branching, length, and concentration. Novel silicone hydrogel lenses were produced and evaluated for optical transmittance, elastic modulus, oxygen transmissibility, water content, and surface wettability. Several lenses met commercial standards and demonstrated an increase in oxygen permeability (Dk) and inverse relationship with elastic modulus and siloxane concentration, respectively. A hydrophobic/hydrophilic ratio below 1.4 was needed for a co‐continuous water phase. Substitution of methoxypropyl groups for butyl groups increased hydrophobic microdomains leading to decreased optical quality and mechanical properties. Generally, fluorine‐containing silicone macromers allowed for a wider range of successful compositions, and above a certain hydrophilic composition, the presence of trifluoropropyl groups resulted in improved solubility and optically clear lenses. Data also showed asymmetric siloxane macromers have potential to meet critical lens properties at lower overall siloxane content. New lens materials with wider composition ranges meeting all clinical lens properties is a significant challenge and may significantly expand the field.
Research Interests: Ophthalmology, Vision Science, Polymer Chemistry, Hydrogels, Contact Lenses, and 14 moreWettability, Medical Device, Biointerfaces, Optometry and Vision Science, polymer science and Engineering, Polymer Permeability, Polysiloxanes, Organosilicon Compounds, Biocompatible Materials, Siloxanes, Macromers, Siloxane and Silicone Polymers, Rigid Gas Permeable Lenses (RGP), and heterotelechelic polymers
A vapor deposition process is provided for the growth of as-deposited hydrogen-free silicon carbide (SiC) and SiC films including oxygen (SiC:O) thin films. For producing the SiC thin films, the process includes providing a... more
A vapor deposition process is provided for the growth of as-deposited hydrogen-free silicon carbide (SiC) and SiC films including oxygen (SiC:O) thin films. For producing the SiC thin films, the process includes providing a silahydrocarbon precursor, such as TSCH (1,3,5-trisilacyclohexane), in the vapor phase, with or without a diluent gas, to a reaction zone containing a heated substrate, such that adsorption and decomposition of the precursor occurs to form stoichiometric, hydrogen-free, silicon carbide (SiC) in a 1:1 atom ratio between silicon and carbon on the substrate surface without exposure to any other reactive chemical species or co-reactants. For the SiC:O films, an oxygen source is added to the reaction zone to dope the SiC films with oxygen. In the silahydrocarbon precursors, every carbon atom is bonded to two silicon atoms, with each silicon atom being additionally bonded to two or more hydrogen atoms.
Research Interests:
Stoichiometric silicon carbide (SiC) thin films were grown using thermal chemical vapor deposition (TCVD) from the single source precursor 1,3,5-trisilacyclohexane (TSCH) on c-Si (100) substrates within an optimized substrate temperature... more
Stoichiometric silicon carbide (SiC) thin films were grown using thermal chemical vapor deposition (TCVD) from the single source precursor 1,3,5-trisilacyclohexane (TSCH) on c-Si (100) substrates within an optimized substrate temperature window ranging from 650 to 850°C. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analyses revealed that the as-deposited films consisted of a Si-C matrix with a Si:C ratio of ~1:1. FTIR and photoluminescence (PL) spectrometry studies showed that films deposited ≥ 750°C were defect- and H-free within the detection limit of the techniques used, while ellipsometry measurements yielded an as-grown SiC average refractive index of ~2.7, consistent with the reference value for the 3C-SiC phase. The exceptional quality of the films appears sufficient to overcome limitations associated with structural defects ranging from failure in high voltage, high temperature electronics to 2-D film growth. TSCH, a liquid at room temperature with good structural stability during transport and handling as well as high vapor pressure (~10 torr at 25°C), provides a viable single source precursor for the growth of stoichiometric SiC without the need for post-deposition thermal treatment.
Research Interests: Microelectronics And Semiconductor Engineering, Materials Science, Chemical Vapor Deposition, SIC, Thin Films and Nanotechnology, and 8 moreSilicones Chemistry, PVD, CVD, ALD, Heterocycles, Silicon Carbide (SiC), Organosilicon Compounds, Silicon Carbide Power Devices, Solid State Physics- Thin films for Optoelectronic Applications, and photoluminescence (PL)
A method for deposition of a thin film onto a substrate is provided. The method includes providing a source precursor containing on or more of elements constituting the thin film, generating a transient species from the source precursor,... more
A method for deposition of a thin film onto a substrate is provided. The method includes providing a source precursor containing on or more of elements constituting the thin film, generating a transient species from the source precursor, and depositing a thin film onto the substrate from the transient species. The transient species being a reactive intermediate that has a limited lifetime in a condensed phase at or above room temperature. An example of epitaxial silicon deposition from the transient intermediate bis(trihydridosilyl)silylene, derived from isotetrasilane, is provided.
Research Interests:
Novel N-alkyl substituted perhydridocyclic silazanes, oligomeric N-alkyl perhydridosilazane compounds, and N-alkylaminodihydridohalosilanes, and a method for their synthesis are provided. The novel compounds may be used to form high... more
Novel N-alkyl substituted perhydridocyclic silazanes, oligomeric N-alkyl perhydridosilazane compounds, and N-alkylaminodihydridohalosilanes, and a method for their synthesis are provided. The novel compounds may be used to form high silicon nitride content films by thermal or plasma induced decomposition. Keywords: Organosilicon; Silicon Nitride; Triisopropylcyclotrisilazane
Research Interests:
Increasingly precise control of polymer architectures generated by “Living” Anionic Ring-Opening Polymerization (Living AROP) is leading to a broad range of commercial ad-vanced material applications, particularly in the area of siloxane... more
Increasingly precise control of polymer architectures generated by “Living” Anionic Ring-Opening Polymerization (Living AROP) is leading to a broad range of commercial ad-vanced material applications, particularly in the area of siloxane macromers. While academic reports on such materials remain sparse, a significant portion of the global population interacts with them on a daily basis—in applications including medical devices, microelectronics, food packaging, synthetic leather, release coatings, and pigment dispersions. The primary driver of this increased utilization of siloxane macromers is their ability to incorporate the properties of silicones into organic structures in a balanced manner. Compared to organic polymers, the differentiating properties of silicones—low Tg, hydrophobicity, low surface energy, and high free molal space—logically lend themselves to applications in which low modulus, release, permeability to oxygen and moisture, and tactile interaction are desired. However, their mechanical, structural and processing properties have until recently precluded practical applications. This review presents applications of “Living” AROP derived polymers from the perspective of historical technology development. Applications in which products are produced on a commercial scale—defined as not only offered for sale, but sold on a recurrent basis—are emphasized. Hybrid polymers with intriguing nanoscale morphology and potential applications in photoresist, microcontact printing, biomimetic soft materials, and liquid crystals are also discussed. Previously unreported work by the authors is provided in the context of this review. Keywords: Breathable Films; Block Polymers; Silicones; Double Gyroid; Self-Healing Polymers; Ultra-high Elongation Elastomers; Release Coatings; Photoresists; siloxanes
Research Interests: Polymer Chemistry, Membranes, Thin Films and Coatings, Liquid Crystals, Elastomers, and 15 morePolymer synthesis, Block Copolymer, Contact Lenses, Functional Polymers, Self-healing materials, Polymer Morphology, Surface and Coatings Technology, Photoresists, Hybrid Polymers, Ring Opening Polymerization, Macromers, Siloxane and Silicone Polymers, Coatings and Adhesives, Bottle-Brush Polymers, and heterotelechelic polymers
A thin film deposition process is provided. The process includes, in a single cycle, providing a precursor in the vapor phase with or without a carrier gas to a reaction zone containing a substrate, such that a monolayer of the precursor... more
A thin film deposition process is provided. The process includes, in a single cycle, providing a precursor in the vapor phase with or without a carrier gas to a reaction zone containing a substrate, such that a monolayer of the precursor is adsorbed to a surface of the substrate and the adsorbed monolayer subsequently undergoes conversion to a discrete atomic or molecular layer of a thin film, without any intervening pulse of or exposure to other chemical species or co-reactants. keywords: semiconductor fabrication; vapor deposition; cobalt
Research Interests:
Results are presented from an exploratory study of near-room-temperature pulsed deposition of SiCxNy thin films using 1,3,5-tri(isopropyl)cyclotrisilazane (TICZ, C9H27N3Si3) and soft remote ammonia (NH3) plasma co-reactants. The process... more
Results are presented from an exploratory study of near-room-temperature pulsed deposition of SiCxNy thin films using 1,3,5-tri(isopropyl)cyclotrisilazane (TICZ, C9H27N3Si3) and soft remote ammonia (NH3) plasma co-reactants. The process involved four pulses: thermal adsorption of TICZ to the substrate at very low temperature, nitrogen (N2) purge, soft NH3 remote plasma step, and N2 purge. These steps were repeated until the desired film thickness was reached. The ratio of C to N in the films was modulated by controlling the substrate temperature in the range of 30 to 200° C. In-situ analysis of the deposition process was carried-out using spectroscopic ellipsometry, and the films were analyzed by x-ray photoelectron spectroscopy (XPS). The findings of this study indicate that the combination of reduced substrate thermal budget and soft remote plasma provides an optimum low energy environment for the controlled deposition of SiCxNy protective coatings on thermally fragile, chemically sensitive substrates, including plastics and polymers. key words: silicon carbonitride; thin films
Research Interests: Thin Films and Coatings, Semiconductor Manufacturing, Nanofabrication, Thin film technology for electrical and electronic applications, Chemical Vapor Deposition, and 8 moreSemiconductor Materials, Silicon Carbide, Silicon Nitride, PVD, CVD, ALD, Silicon Carbon Nitride, Atomic Layer Deposition (ALD), Organosilicon Compounds, and Si3N4
High-quality silicon nitride (SiN x) thin films were grown by remote-plasma-activated pulsed chemical vapor deposition (P-CVD) from the source precursor 1,3,5-tri(isopropyl)cyclotrisilazane (TICZ, C 9 H 27 N 3 Si 3) and remote ammonia (NH... more
High-quality silicon nitride (SiN x) thin films were grown by remote-plasma-activated pulsed chemical vapor deposition (P-CVD) from the source precursor 1,3,5-tri(isopropyl)cyclotrisilazane (TICZ, C 9 H 27 N 3 Si 3) and remote ammonia (NH 3) plasma on silicon oxide (SiO 2) substrates within an optimized substrate temperature window ranging from 200 to 350 °C. TICZ was selected because of its chemical stability, non-pyrophoric nature, good vapor pressure (~127 Pa at 70 °C), and its chemical structure that incorporates alkyl groups with three C atoms on each N atom, which provides a clean elimination mechanism for low temperature SiN x deposition. P-CVD consisted of a four-step process: TICZ pulse with no plasma, N 2 purge, NH 3 plasma pulse, and N 2 purge. The as-deposited films were analyzed using spectroscopic ellipsometry and x-ray photoelectron spectroscopy (XPS). Wet etch rates were determined using a standard solution consisting of 0.5% hydrofluoric acid in deionized water. XPS analysis revealed a Si:N ratio of ~1:1 within the entire substrate temperature range and validated the formation of the SiN x phase. In situ, real-time ellipsometry measurements confirmed that SiN x growth exhibited a non-self-limiting P-CVD behavior. They also yielded an as-grown SiN x average refractive index of ~1.8 for the films grown at substrate temperatures above 200 °C.
Research Interests: Thin Films and Coatings, Nanofabrication, Thin Films, Thin Film Deposition and Surface Modification, Nitrides, and 8 moreSilicon Nitride, Plasma Enhanced Chemical vapour deposition (PECVD), Thin Films and Nanotechnology, PVD, CVD, ALD, Organosilicon Compounds, Dielectric Materials, Si3N4, and Nitride Films
Accelerating interest in silicon nitride thin film material system continues in both academic and industrial communities due to its highly desirable physical, chemical, and electrical properties and the potential to enable new device... more
Accelerating interest in silicon nitride thin film material system continues in both academic and industrial communities due to its highly desirable physical, chemical, and electrical properties and the potential to enable new device technologies. As considered here, the silicon nitride material system encompasses both non-hydrogenated (SiNx) and hydrogenated (SiNx:H) silicon nitride, as well as silicon nitride-rich films, defined as SiNx with C inclusion, in both non-hydrogenated (SiNx(C)) and hydrogenated (SiNx:H(C)) forms. Due to the extremely high level of interest in these materials, this article is intended as a follow-up to the authors’ earlier publication [A. E. Kaloyeros, F. A. Jové, J. Goff, B. Arkles, Silicon nitride and silicon nitride-rich thin film technologies: trends in deposition techniques and related applications, ECS J. Solid State Sci. Technol., 6, 691 (2017)] that summarized silicon nitride research and development (R&D) trends through the end of 2016. In this survey, emphasis is placed on cutting-edge achievements and innovations from 2017 through 2019 in Si and N source chemistries, vapor phase growth processes, film properties, and emerging applications, particularly in heterodevice areas including sensors, biointerfaces and photonics.
Research Interests: Microelectronics And Semiconductor Engineering, Nanomaterials, Nanotechnology, Refractory materials and coatings for thermal barrier and tribology applications, Chemical Vapor Deposition, and 10 moreSemiconductor Materials, Surface modification, Thin Film Deposition and Surface Modification, Nitrides, Silicon Nitride, Plasma Enhanced Chemical vapour deposition (PECVD), Biointerfaces, PVD, CVD, ALD, Thin Film Dielectrics, and Si3N4
Thiasilacyclopentane (TSCP) and azasilacyclopentane (ASCP) heteroatom cyclics have proven capable of rapidly converting hydroxylated surfaces to functionalized surfaces in inorganic click reactions. In this work, we demonstrate that the... more
Thiasilacyclopentane (TSCP) and azasilacyclopentane (ASCP) heteroatom cyclics have proven capable of rapidly converting hydroxylated surfaces to functionalized surfaces in inorganic click reactions. In this work, we demonstrate that the use of these reagents can be extended to "simultaneous double-clicking" when both inorganic and organic substrates are present at the onset of the reaction. The simultaneous double-click depends on a first ring-opening click with an inorganic substrate that is complete in ∼1 s at 30°C and results in the reveal of a cryptic mercaptan or secondary amine group, which can then participate in a second click with an organic substrate. TSCPs and ASCPs can take part in tandem double-click reactions in which the organic substrate is added to the reaction mixture after the initial inorganic click reaction is completed. Additionally, ASCPs with exocyclic functionality, specifically N-alkenyl-, N-aminoalkyl, and N-alkynyl-ASCPs, are shown to be options for tandem double-clicking in which functionalization proceeds in two independent steps and the sequence of the double-click reaction can be reversed.
Research Interests: Materials Science, Thin Films and Coatings, Glass, Nanofabrication, Nanoparticles, and 15 moreClick chemistry, Crack propagation, Tacrolimus, Surface modification, Thin Film Deposition and Surface Modification, Self-assembled monolayers (SAMs), Click Chemistry in Polymers, PVD, CVD, ALD, CVD Coatings, Thiol-ene Chemistry, Foreign Body Response, Interphase, Molecular Layer Deposition (MLD), Areas Specific Deposition, and Silane coupling agents
Cobalt metallic films are the subject of an ever-expanding academic and industrial interest for incorporation into a multitude of new technological applications. This report reviews the state-of-the art chemistry and deposition techniques... more
Cobalt metallic films are the subject of an ever-expanding academic and industrial interest for incorporation into a multitude of new technological applications. This report reviews the state-of-the art chemistry and deposition techniques for cobalt thin films, highlighting innovations in cobalt metal-organic chemical vapor deposition (MOCVD), plasma and thermal atomic layer deposition (ALD), as well as pulsed MOCVD technologies, and focusing on cobalt source precursors, thin and ultrathin film growth processes, and the resulting effects on film composition, resistivity and other pertinent properties.
Research Interests: Thin Films and Coatings, Nanofabrication, Organometallic Chemistry, Nanotechnology, Thin film technology for electrical and electronic applications, and 10 moreAtomic Layer Deposition, Chemical Vapor Deposition, Semiconductor Materials, MOCVD, Nanotechnology, Nanoelectronics, Semiconductor nanostructured optoelectronic Devices, Cobalt, Cobalt Oxide, Metallization, Metal Organic Chemical Vapor Deposition, and Area Selective Deposition
The need for tighter control over film uniformity, conformality, and properties at decreasing thicknesses was met by a gradual evolution from physical vapor deposition (PVD), to chemical vapor deposition (CVD), and eventually atomic layer... more
The need for tighter control over film uniformity, conformality, and properties at decreasing thicknesses was met by a gradual evolution from physical vapor deposition (PVD), to chemical vapor deposition (CVD), and eventually atomic layer deposition (ALD) processes. Of all manufacturing-worthy thin-film deposition processes, ALD has the greatest potential to satisfy these requirements. However, the intrinsic constraints of recurrent two atom reactivity and associated byproducts have kindled tremendous interest in other self-limiting deposition processes such as Molecular Layer Deposition (MLD), Self-Assembled Monolayer (SAM), and “Click” Chemistry Deposition (CCD) processes, either as alternatives to or in conjunction with ALD. This overview provides definitions, illustrations and examples of these processes.
Research Interests: Microelectronics And Semiconductor Engineering, Semiconductor Nanostructures, Thin Films and Coatings, Nanofabrication, Nanotechnology, and 12 moreSurface Engineering, Surface Chemistry, Chemical Vapor Deposition, Thin Films, Click chemistry, Semiconductor Materials, Surface Coatings, Self-assembled monolayers (SAMs), Surface and Coatings Technology, PVD, CVD, ALD, Organosilicon Compounds, and Ring-opening Reactions
This article provides an overview of the state-of-the-art chemistry and processing technologies for silicon nitride and silicon nitride-rich films, i.e., silicon nitride with C inclusion, both in hydrogenated (SiN x :H and SiN x :H(C))... more
This article provides an overview of the state-of-the-art chemistry and processing technologies for silicon nitride and silicon nitride-rich films, i.e., silicon nitride with C inclusion, both in hydrogenated (SiN x :H and SiN x :H(C)) and non-hydrogenated (SiN x and SiN x (C)) forms. The emphasis is on emerging trends and innovations in these SiN x material system technologies, with focus on Si and N source chemistries and thin film growth processes, including their primary effects on resulting film properties. It also illustrates that SiN x and its SiN x (C) derivative are the focus of an ever-growing research and manufacturing interest and that their potential usages are expanding into new technological areas.
Research Interests: Microelectronics And Semiconductor Engineering, Ceramic Technology, Thin Films and Coatings, Mechanical Behavior Of Materials, Refractory materials and coatings for thermal barrier and tribology applications, and 15 moreChemical Vapor Deposition, Thin Films, Semiconductor Materials, Nitrides, Silicon Nitride, Advanced Ceramics, PVD, CVD, ALD, Atomic Layer Deposition (ALD), Organosilicon Compounds, Nano Fabrication, Dielectric Materials, Thin Film Dielectrics, Polysilazane, Preceramic polymers, and Si3N4
ExSil silicone nanocomposites are the first in a series of ultra-high elongation materials that achieve their unique mechanical properties via a radically different mechanism than traditional silicones. This distinct class of silicone... more
ExSil silicone nanocomposites are the first in a series of ultra-high elongation materials that achieve their unique mechanical properties via a radically different mechanism than traditional silicones. This distinct class of silicone elastomer exhibits surprising material properties, such as up to 5,000% stretchability with elastic recovery, the ability to resist tear failure (both initiation and propagation), self-healing/sealing behavior and intrinsically low extractables. As a group, these materials demonstrate an ability to resist and recover from conditions that would normally result in the failure of other elastomers.
Research Interests: Biomedical Engineering, Polymer Chemistry, Biomaterials, Microfluidics, Medical Device Design, and 15 moreNanocomposites, Knot Theory, Elastomers, Biomedical Materials, Self-healing materials, Silicone, polymer science and Engineering, Soft materials, Implant-soft tissue interface, Rubber technology, Silicones Chemistry, Biocompatible Materials, Artificial Skin, Siloxane and Silicone Polymers, and Stretchable and Flexible Materials
Heterocyclic silanes containing Si−N or Si−S bonds in the ring undergo a ring opening reaction with −OH groups at the surface of porous Si nanostructures to generate −SH or −NH functional surfaces, grafted via O−Si bonds. The reaction is... more
Heterocyclic silanes containing Si−N or Si−S bonds in the ring undergo a ring opening reaction with −OH groups at the surface of porous Si nanostructures to generate −SH or −NH functional surfaces, grafted via O−Si bonds. The reaction is substantially faster (0.5−2 h at 25 °C) and more efficient than hydrolytic condensation of trialkoxysilanes on similar hydroxy-terminated surfaces, and the reaction retains the open pore structure and photoluminescence of the quantum-confined silicon nanostructures. The chemistry is sufficiently mild to allow trapping of the test protein lysozyme, which retains its enzymatic activity upon release from the modified porous nanostructure.
Research Interests: Heterocyclic chemistry, Nanophotonics, Silicon, Nanoparticles, Electroluminescent Materials, and 14 moreDrug Delivery System, Surface Chemistry, Click chemistry, Surface modification, Porous Silicon, Self-assembled monolayers (SAMs), Nano Fabrication and Thin Film Technology, Silicon Nanoparticles, Organosilicon Compounds, Interphase, Molecular Layer Deposition (MLD), Area Specific Deposition, Silane coupling agents, and Adhesion Promotion
Silicone elastomers with elongations approaching 5000% are now available. These elongations are nearly 4 times greater than any commercial elastomer. The new elastomers utilize a cure mechanism which generates elastomeric properties by... more
Silicone elastomers with elongations approaching 5000% are now available. These elongations are nearly 4 times greater than any commercial elastomer. The new elastomers utilize a cure mechanism which generates elastomeric properties by driving linear polymers to extremely high molecular weights with concomitant formation of intra-chain and inter-chain entanglements rather than covalent cross-linking. When elastomers have elongations significantly above 1500%, they exhibit behavior that is readily differentiated from conventional elastomers . Tear propagation mechanisms are altered and tear failure occurs at radically greater elongations. The polymer chemistry relies upon step-growth polymerization of heterobifunctional siloxane macromers produced by anionic ring-opening polymerization.
Research Interests: Polymer Chemistry, Soft Matter, Elasticity (Solid Mechanics), Mechanical Behavior Of Materials, Elastomers, and 15 moreRubbers (Materials), Polymer synthesis, Polymer Nanocomposites, Polymer networks, Rubber, polymer science and Engineering, Silicones Chemistry, Knot Theory, Molecular Biology, Polymer Physics, Polysiloxanes, Silicone Rubber, Biocompatible Materials, Anionic Polymerization, Tear Strength, Stretchable and Flexible Materials, and heterotelechelic polymers
Organic trihydridosilanes can be grafted to hydrogen terminated porous Si nanostructures with no catalyst. The reaction proceeds efficiently at 80 8C, and it shows little sensitivity to air or water impurities. The modified surfaces are... more
Organic trihydridosilanes can be grafted to hydrogen terminated porous Si nanostructures with no catalyst. The reaction proceeds efficiently at 80 8C, and it shows little sensitivity to air or water impurities. The modified surfaces are stable to corrosive aqueous solutions and common organic solvents. Octadecylsilane H 3 Si(CH 2) 17 CH 3 , and functional silanes H 3 Si(CH 2) 11 Br, H 3 Si(CH 2) 9 CH = CH 2 , and H 3 Si(CH 2) 2-(CF 2) 5 CF 3 are readily grafted. When performed on a mesopo-rous Si wafer, the perfluoro reagent yields a superhydrophobic surface (contact angle 1518). The bromo-derivative is converted to azide, amine, or alkyne functional surfaces via standard transformations, and the utility of the method is demonstrated by loading of the antibiotic ciprofloxaxin (35 % by mass). When intrinsically photoluminescent porous Si films or nanoparticles are used, photoluminescence is retained in the grafted products, indicating that the chemistry does not introduce substantial nonradiative surface traps.
Research Interests: Nanofabrication, Electroluminescent Materials, Thin film technology for electrical and electronic applications, Surface Chemistry, Metal Hydrides, and 12 morePorous Silicon, Self-assembled monolayers (SAMs), Surface treatment, Self-Assembled Monolayer of Nanoparticles, Silicones Chemistry, Silicon Nanoparticles, Organosilicon Compounds, Area Selective Deposition, Dehydrocoupling, Silane coupling agents, hydrogen terminated silicon, and Dissociative Adsorption
Elastomeric polysiloxane nanocomposites with elongations of >5000% (more than 3× greater than any previously reported material) with excellent shape recovery are presented.This development is enabled by a living polymerization that... more
Elastomeric polysiloxane nanocomposites with elongations of >5000% (more than 3× greater than any previously reported material) with excellent shape recovery are presented.This development is enabled by a living polymerization that results in heterobifunctional poly(dimethylsiloxane) (PDMS) macromonomers of intermediate molecular weight. A step-growth hydrosilylation reaction results in highly deformable materials that are desirable for the fabrication of stretchable implants and microfluidic devices. No cross-linking or domain formation is observed by a variety of analytical techniques, suggesting that their elastomeric behavior is caused by polymer chain entanglements.
Research Interests: Materials Science, Polymer Chemistry, Polymer science, Soft Matter, Mechanical Behavior Of Materials, and 15 moreElastomers, Rubbers (Materials), Mechanical Behaviour of Materials, Elasticity, Biomedical Materials, Polymer networks, polymer science and Engineering, Knot Theory, Molecular Biology, Polymer Physics, Silicone Rubber, Biocompatible Materials, Siloxane and Silicone Polymers, Ultra-stretchability, Stretchable and Flexible Materials, heterotelechelic polymers, and Elastic Behavior
2-(p-t-Butylphenyl)ethylsilanes are provided having the general formula: Si(B)(R)(A), wherein B is a (p-t-butylphenyl)ethyl moiety, R is an alkyl or aryl moiety and A is a hydrolyzeable moiety; x equals 1 or 2, y equals 0, 1 or 2 and Z... more
2-(p-t-Butylphenyl)ethylsilanes are provided having the general formula: Si(B)(R)(A), wherein B is a (p-t-butylphenyl)ethyl moiety, R is an alkyl or aryl moiety and A is a hydrolyzeable moiety; x equals 1 or 2, y equals 0, 1 or 2 and Z equals 1, 2 or 3 such that x plus y plus z equals 4. The bulky substituted silanes are produced by the hydrosilylation of p-t-butylstyrene.
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Silsesquioxanes containing beta-acetoxyethyl (BAE) groups are processible resins that can be employed as spin-on-glass precursors to dielectric silica films. Thermal treatment >250 'C results in extrusion of ethylene from the CH2CH2COOCH3... more
Silsesquioxanes containing beta-acetoxyethyl (BAE) groups are processible resins that can be employed as spin-on-glass precursors to dielectric silica films. Thermal treatment >250 'C results in extrusion of ethylene from the CH2CH2COOCH3 moiety with formation of Si-COOCH3 groups, which undergo facile hydrolysis to a silica network. A minor pathway involving extrusion of acetic acid leaves some silicon vinyl groups, leading to residual organic carbon in the material. However, addition of a fluoride ion catalyst greatly accelerates the major reaction, resulting in lower conversion temperatures (<200 'C), quantitative extrusion of ethylene, and essentially pure silica. Alternatively, BAESSQs can be processed photochemically (X<200 nm) to cleanly yield silica at ambient temperature.
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Hydrophilic N-acylamino acid; N-acyl dipeptide; and N-acyl tripeptide substituted silanes are prepared which can be utilized as reactive surface treatments for particles of pigments; minerals; and fillers. These treated particles form... more
Hydrophilic N-acylamino acid; N-acyl dipeptide; and N-acyl tripeptide substituted silanes are prepared which can be utilized as reactive surface treatments for particles of pigments; minerals; and fillers. These treated particles form stable dis persions in the aqueous phase of oil-in-water mixtures that are suitable for cosmetic applications. The treated particles may also be used in pressed powder and color cosmetic formulations.
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A new class of cyclotrisiloxanes having alkyl ether substituents on one, two, or three of the ring silicon atoms and a method for their preparation are provided. These compounds undergo living anionic ring-opening polymerization to... more
A new class of cyclotrisiloxanes having alkyl ether substituents on one, two, or three of the ring silicon atoms and a method for their preparation are provided. These compounds undergo living anionic ring-opening polymerization to generate unique polymer structures that introduce hydrophilicity to siloxane polymers.. A new class of hydridosilylethylcyclotrisiloxanes is also described.
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Germanium compounds have emerged as critically important materials in the fabrication of microelectronics, optics and sensors. Potential new applications in organic transformations and polymer synthesis have also been reported. This... more
Germanium compounds have emerged as critically important materials in the fabrication of microelectronics, optics and sensors. Potential new applications in organic transformations and polymer synthesis have also been reported. This article highlights some of the chemistry associated with these applications. It also compares and
contrasts the chemistry of germanium with the more widely understood chemistry of silicon. For readers with a deeper interest in the chemistry of germanium, comprehensive reviews provide a detailed description.1,2,3,4,5
contrasts the chemistry of germanium with the more widely understood chemistry of silicon. For readers with a deeper interest in the chemistry of germanium, comprehensive reviews provide a detailed description.1,2,3,4,5
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Titanates utilized in catalysis, surface modification and thixotropic applications are discussed.
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Low molecular weight siloxane materials having one functional group are provided which have reduced tendency to form phase separated domains after polymerization. Two classes of siloxane materials are included: (1) symmetric siloxane... more
Low molecular weight siloxane materials having one functional group are provided which have reduced tendency to form phase separated domains after polymerization. Two classes of siloxane materials are included: (1) symmetric siloxane macromonomers containing at least two monomer termini and one polymerizable functional group which is equidistant from the termini, and (2) assymetric siloxane macromonomers having at least one polymerizable functional group terminus and at least one oxygen-containing polar hydrophilic terminus selected from the group consisting of hydroxyl, ether, and polyether. Symmetric siloxane macromonomers having hydroxyl termini are useful for forming biocompatible materials, such as for contact lenses, tissue regeneration scaffold polymers, and coatings to reduce non-specific binding of proteins.
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A class of volatile cyclic and acyclic azasilanes is provided as well as methods for their preparation which comprise heating aminoalkoxysilanes in the presence of an ammonium salt, sulfuric acid, or phosphonium salt. The cyclic... more
A class of volatile cyclic and acyclic azasilanes is provided as well as methods for their preparation which comprise heating aminoalkoxysilanes in the presence of an ammonium salt, sulfuric acid, or phosphonium salt. The cyclic azasilanes may be used for the treatment of inorganic surfaces, particularly nanoparticles, by a ring-opening reaction when non-hydrolytic deposition methods are required.
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Two classes of cyclic tin compounds, trioxa-aza-1-stannabicyclo-[3.3.3]-undecanes, also referred to as stannatranes and tetraaza-1-stannabicyclo-[3.3.3]-undecanes also referred to as azastannatranes are described as are methods for their... more
Two classes of cyclic tin compounds, trioxa-aza-1-stannabicyclo-[3.3.3]-undecanes, also referred to as stannatranes and tetraaza-1-stannabicyclo-[3.3.3]-undecanes also referred to as azastannatranes are described as are methods for their preparation. These cyclic tin compounds are resistant to rearrangement and the generation of dialkyltin impurities is not observed during the synthesis, purification or deposition of these compounds to form oxostannate films.
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Silylene Transfer Reactions for Synthesis of Strained Alkenes, Keith Woerpel; Methylsilicones Pushed in Several Directions, Thomas McCarthy; N-Heterocyclic Silylenes, Matthias Dreiss; Surface Modification of Silicon Nanostructures;... more
Silylene Transfer Reactions for Synthesis of Strained Alkenes, Keith Woerpel; Methylsilicones Pushed in Several Directions, Thomas McCarthy; N-Heterocyclic Silylenes, Matthias Dreiss; Surface Modification of Silicon Nanostructures; Michael Sailor; Silicon-Hybrid Materials, Joseph Mabry; Silicon Nanocrystal Assemblies; Brian Korgel; New Materials Properties Through a Silicone Blend Strategy, Francois Ganachaud; New Methods for Tethered Carbonyl Silylations, Gregory O'Neil; Advances in Preparation of Organosilanes Using Palladium Catalysis, Donald Watson; Synthesis and Applications of Silicone Copolymers, Ramesh Kumar; Towards Controlled Synthesis and Characterization of Complex Silicone Architectures; Use of Nanocatalysis in the Direct Synthesis of Methylchlorosilanes and Alkoxysilanes; Kendrick Lewis; Material Behavior of Self-Aligned Silicon Carbide Nanowire Arrays; Spyros Gallis; Cyclohexasilane, A Source of Quantum Dots, Nanowires, Philip Boudjouk; Mechanism of Oligomerizatio...
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A serious approach to barbecue written in whimsical style.
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Results are presented from a systematic study of the composition, texture, and electrical properties of titanium nitride (TiN) films and their performance as diffusion barrier in multilevel interconnect schemes of ultralarge scale... more
Results are presented from a systematic study of the composition, texture, and electrical properties of titanium nitride (TiN) films and their performance as diffusion barrier in multilevel interconnect schemes of ultralarge scale integration (ULSI) computer chip device structures. The films were grown by low temperature (<450°C) inorganic chemical vapor deposition using titanium tetraiodide as source precursor and ammonia and hydrogen as co‐reactants. The TiN films were nitrogen‐rich., with iodine concentrations below 2 atom percent, displayed resistivities in the range 100 to 150 μΩ cm depending on thickness, and exhibited excellent step coverage with better than 90% conformality in both nominal 0.45 μm, 3:1 aspect ratio and 0.25 μm, 4:1 aspect ratio contact structures. A comparison of the properties of chemical vapor deposited (CVD) TiN with equivalent physical vapor deposited (PVD) TiN showed that reactivity with Al‐0.5 a/o Cu alloys was equivalent in both cases. In particular, a 10% increase in the Al‐Cu/TiN stack sheet resistance was observed for both types of TiN after a 450°C, 30 min sinter. Similarly, the characteristics of CVD tungsten and reflow plug fills were identical on both types of TiN films. However, barrier performance for CVD TiN in aluminum and tungsten plug technologies was superior to that of PVD TiN, as evidenced by lower contact diode leakage for CVD TiN in comparison with PVD TiN films of equal thickness. This improved barrier performance could be attributed to a combination of factors, which include the nitrogen‐rich composition, higher density, and enhanced conformality of the CVD TiN phase in comparison with the PVD TiN. In view of the superior step coverage and diffusion barrier characteristics, the low temperature inorganic CVD route to TiN seems to provide an adequate replacement for conventional PVD TiN in emerging ULSI metallization interconnect schemes.
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Silsesquioxane polymers that are useful for preparing SiO2 -rich ceramic coatings are obtained as the polymeric reaction products from the hydrolysis and condensation of organosilanes having a β-substituted alkyl group. A preferred... more
Silsesquioxane polymers that are useful for preparing SiO2 -rich ceramic coatings are obtained as the polymeric reaction products from the hydrolysis and condensation of organosilanes having a β-substituted alkyl group. A preferred silsesquioxane polymer is the polymeric reaction product obtained from β-chloroethyltrichlorosilane. More preferred silsesquioxones are those with non-halogenated alkyl groups, such as the β.-acetoxyethyl- and β-hydroxyethyl-silsesquioxones. Coating compositions containing such silsesquioxane polymers dissolved in organic solvent may be applied to a substrate and converted to SiO2 -rich ceramic thin layers by evaporating the solvent and heating the coated substrate at moderate temperatures.
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A new classification system allows designers to select silicone fluids on their primary function and properties rather than chemical structure. Mechanical, thermal, lubrication and compatibility properties of a wide range of commercial... more
A new classification system allows designers to select silicone fluids on their primary function and properties rather than chemical structure. Mechanical, thermal, lubrication and compatibility properties of a wide range of commercial silicone fluids are presented.
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Organosilanes remain a largely untapped resource as pharmaceuticals. The vast array of organosilane intermediates currently available, coupled with increasingly powerful synthetic methods for organosilane construction, has led to a... more
Organosilanes remain a largely untapped resource as pharmaceuticals. The vast array of organosilane intermediates currently available, coupled with increasingly powerful synthetic methods for organosilane construction, has led to a renaissance in bioactive organosilane research. This brief review will describe some of the historical highlights of the search for bioactivity in organosilanes and contemporary advances.
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A heterofunctional poly(alkyleneoxide) according to the invention contains a first polymer terminus containing a protected, unprotected, or derivatized amine or aminoalkyl functionality and a second polymer terminus containing an... more
A heterofunctional poly(alkyleneoxide) according to the invention contains a first polymer terminus containing a protected, unprotected, or derivatized amine or aminoalkyl functionality and a second polymer terminus containing an unsaturated functionality. Reaction products, derivatives, and methods of making these materials are also described.
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A heterofunctional poly(alkyleneoxide) according to the invention contains a first polymer terminus containing a protected, unprotected, or derivatized amine or aminoalkyl functionality and a second polymer terminus containing an... more
A heterofunctional poly(alkyleneoxide) according to the invention contains a first polymer terminus containing a protected, unprotected, or derivatized amine or aminoalkyl functionality and a second polymer terminus containing an unsaturated functionality. Reaction products, derivatives, and methods of making these materials are also described.
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A heterofunctional poly(alkyleneoxide) according to the invention contains a first polymer terminus containing a protected, unprotected, or derivatized amine or aminoalkyl functionality and a second polymer terminus containing an... more
A heterofunctional poly(alkyleneoxide) according to the invention contains a first polymer terminus containing a protected, unprotected, or derivatized amine or aminoalkyl functionality and a second polymer terminus containing an unsaturated functionality. Reaction products, derivatives, and methods of making these materials are also described.
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This invention pertains to UV-absorbing coatings that may optionally be covered with an anti-reflective layer and that are applied to exterior-facing surfaces such as a window or other glass surface that are transparent or translucent.... more
This invention pertains to UV-absorbing coatings that may optionally be covered with an anti-reflective layer and that are applied to exterior-facing surfaces such as a window or other glass surface that are transparent or translucent. Such coatings are visible to various species of birds, but are generally transparent to humans. The UV absorbing coatings have a silane- or silane-derived chromophore or a combination of a silane- or siloxane-based material and a chromophore, which chromophores absorb UV light at about 300 to about 400 nm. More particularly, the silane- or siloxane-based chromophore is 2-hydroxy-4-(3-triethoxysilylpropoxy) diphenylketone or a derivative thereof.
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This invention pertains to UV-absorbing coatings that may optionally be covered with an anti-reflective layer and that are applied to exterior-facing surfaces such as a window or other glass surface that are transparent or translucent.... more
This invention pertains to UV-absorbing coatings that may optionally be covered with an anti-reflective layer and that are applied to exterior-facing surfaces such as a window or other glass surface that are transparent or translucent. Such coatings are visible to various species of birds, but are generally transparent to humans. The UV absorbing coatings have a silane- or silane-derived chromophore or a combination of a silane- or siloxane-based material and a chromophore, which chromophores absorb UV light at about 300-400nm. More particularly, the silane- or siloxane- based 2-hydroxy-4-(3-triethoxysilyl-propoxydiphenylketone or a derivative thereof.
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Cellular organelles, examples of which are mitochondria, microsomes and chloroplasts, are bound in an active state on a substantially inert and insoluble support surface, examples of which are alkylated glass, kaolin, talc, silica,... more
Cellular organelles, examples of which are mitochondria, microsomes and chloroplasts, are bound in an active state on a substantially inert and insoluble support surface, examples of which are alkylated glass, kaolin, talc, silica, ferrites, alumina, and some alkyl substituted high molecular weight polymers. Binding between the support surface and the organelle is accomplished by adsorption of the isolated organelle onto the support surface. Immobilization in this manner does not affect the functional behavior of the organelle. These systems have utility for the synthesis of specific chemical substances.
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There are over 100 known channelopathy diseases which are generally described as diseases associated with transport of ions across cell membranes. They include cardiovascular, degenerative neuropathy and renal diseases. For the most part... more
There are over 100 known channelopathy diseases which are generally described as diseases associated with transport of ions across cell membranes. They include cardiovascular, degenerative neuropathy and renal diseases. For the most part channelopathy diseases have been considered "undruggable." Crown ethers have been shown to have physiological effects ascribed to their ionophoric properties. However, high levels of toxicity precluded interest in evaluation as therapeutics. We prepared silacrown analogs of crown ethers. Our initial studies focused on examples of large ring silacrown ethers having at least fourteen ring atoms with at least one lipophilic or hydrophobic substituent on the ring and/or on the silicon atom are provided. The synthesis of silacrown ethers, ionophoric behavior, preliminary toxicity studies, evaluation in human and rabbit atrial tissue and preliminary studies in cardiac myocyte cell lines will be presented and compared to their carbon analogs. For HL-1 cells, an atrial muscle cell line, three different responses were observed for the compounds tested: no effect on Ca +2 or response to KCl-depolarization, strong inhibition of Ca +2 transients with some residual response to KCl-depolarization, and inhibition of Ca +2 transients and no subsequent response to KCl-depolarization.
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The semiconductor industry is being radically impacted by the development of hetero-devices and systems for a wide spectrum of technological applications that are drivers for new materials and decreasing form factors. Material selection... more
The semiconductor industry is being radically impacted by the development of hetero-devices and systems for a wide spectrum of technological applications that are drivers for new materials and decreasing form factors. Material selection has been constrained by existing fabrication process technology, limiting chemical sources or precursors to those that match existing CVD and ALD associated processes. Processing and integration of material structures will require the introduction of novel chemistry and deposition processes, and manufacturing worthy protocols that provide new methods for atomic level control of near-zero-thickness thin films. Potential processes and precursors that embody this strategy include: • P-CVD SiNx: This process combines precursor thermal adsorption and the reaction with remote plasma ammonia. A demonstration is presented in which thermal adsorption of tri(isopropyl)cyclotrisilazane (TICZ) ensures a substrate driven nucleation and growth process that leads ultimately to conformal SiNx in extremely high aspect ratio structures. Concurrently, the application of a remote NH3 plasma eliminates any undesirable plasma-induced effects. • ALD and CVD Through Vapor Phase Transient Species Generation: The discrete generation of disilylsilylene as a transient species in physical and energetic environments distinct from the substrate deposition and the parent precursor supply will be discussed. This process enables the deposition of epitaxial silicon films in lower thermal or energetic substrate environments. It also enables the deposition of films with greater conformality. • Integrated Synthesis and Deposition (ISD): A manufacturing paradigm comprising a method and system for real-time, closed-loop synthesis, supply, and consumption of precursors in IC manufacturing processes. In its simplest form, the system consists of a precursor synthesis chamber being physically interfaced with a thin film processing chamber, with precursor being synthesized on demand and supplied into the thin film processing chamber where it is consumed. This allows highly reactive chemistry that would be considered otherwise unacceptable due to explosive or toxicity concerns. • Area Specific Deposition by Topmost Atomic Layer Modification and Restructuring (ASD-TLM): The selective deposition of dielectric or conducting films enabled by molecular layer deposition (MLD) or self-assembled monolayers (SAMs) will be discussed. Trihydridosilanes can be grafted without catalyst to amorphous hydrogenated silicon, gold and titanium substrates. The mechanism involves dissociative adsorption and dehydrocoupling.
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Elastomers with exceptionally high elongation prepared by "living" anionic ring-opening polymerization are described. Background information on polysiloxane AROP used to produce macromers and heterobifunctional polymers is described. The... more
Elastomers with exceptionally high elongation prepared by "living" anionic ring-opening polymerization are described. Background information on polysiloxane AROP used to produce macromers and heterobifunctional polymers is described. The use of these materials for applications ranging from silicone hydrogel contact lenses to elastomers with elongations approaching 5000% are presented.
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The semiconductor industry is being radically impacted by placing greater emphasis on the development of hetero-devices and systems that will act as essential drivers for a wide spectrum of technological applications across multiple... more
The semiconductor industry is being radically impacted by placing greater emphasis on the development of hetero-devices and systems that will act as essential drivers for a wide spectrum of technological applications across multiple industrial sectors. The introduction of new materials and their integration with currently used materials are projected to replace IC design and device scaling as the key enablers to the realization of improved device performance and larger density gains. Yet material selection has been constrained by existing fabrication process technology. To date, fabrication processes have dictated material selection by limiting chemical sources or precursors to those that match existing process tools associated with CVD and ALD and their variants, which in turn limits material compositions in ICs. The processing and integration of new materials structures will require the introduction of new deposition and etching processes, and manufacturing worthy protocols that provide new methods for atomic level control.
This presentation explores four new such processes and protocols that match these requirements, namely:
• P-CVD SiNx: This process combines precursor thermal adsorption with the reaction with remote plasma ammonia. A demonstration is presented in which thermal adsorption of tri(isopropyl)cyclotrisilazane (TICZ) ensures a substrate driven nucleation and growth process that leads ultimately to conformal SiNx in extremely high aspect ratio structures. Concurrently, the application of a remote NH3 plasma eliminates any undesirable plasma-induced effects on the substrate and growing film.
• Single Pulse CVD/ALD: These are methods for pulsed deposition of thin films that offer significant reduction in the time to generate thin films by eliminating a number of the steps required in growth cycles. In the case of ALD, for instance, it reduces the number of steps required to grow every individual thin film layer from four to one, thus maximizing process efficiency and wafer throughput, and leading to competitive manufacturing cost of ownership and return on investment. The deposition of high quality cobalt films from cobalt tricarbonyl nitrosyl will be discussed in this context.
• Vapor Phase Transient Species Deposition. The discrete generation of transient species under conditions distinct from the substrate and the parent precursor will be discussed. This process enables the deposition of films in lower thermal or energetic substrate environments. It also enables the deposition of films at lower temperatures and ensures greater conformality of the deposited films, allowing film deposition on thermally or chemically fragile substrates.
• Integrated Synthesis and Deposition (ISD): A manufacturing paradigm comprising a method and system for real-time, closed-loop synthesis, supply, and consumption of precursors in IC manufacturing processes. In its simplest form, the system consists of a precursor synthesis chamber being physically interfaced with a thin film processing chamber, with precursor being synthesized on demand and supplied in a controlled fashion into the thin film processing chamber where it is consumed in the manufacturing process. This allows practical methods to employ highly reactive chemistry that otherwise could lead to explosive or highly toxic releases.
This presentation explores four new such processes and protocols that match these requirements, namely:
• P-CVD SiNx: This process combines precursor thermal adsorption with the reaction with remote plasma ammonia. A demonstration is presented in which thermal adsorption of tri(isopropyl)cyclotrisilazane (TICZ) ensures a substrate driven nucleation and growth process that leads ultimately to conformal SiNx in extremely high aspect ratio structures. Concurrently, the application of a remote NH3 plasma eliminates any undesirable plasma-induced effects on the substrate and growing film.
• Single Pulse CVD/ALD: These are methods for pulsed deposition of thin films that offer significant reduction in the time to generate thin films by eliminating a number of the steps required in growth cycles. In the case of ALD, for instance, it reduces the number of steps required to grow every individual thin film layer from four to one, thus maximizing process efficiency and wafer throughput, and leading to competitive manufacturing cost of ownership and return on investment. The deposition of high quality cobalt films from cobalt tricarbonyl nitrosyl will be discussed in this context.
• Vapor Phase Transient Species Deposition. The discrete generation of transient species under conditions distinct from the substrate and the parent precursor will be discussed. This process enables the deposition of films in lower thermal or energetic substrate environments. It also enables the deposition of films at lower temperatures and ensures greater conformality of the deposited films, allowing film deposition on thermally or chemically fragile substrates.
• Integrated Synthesis and Deposition (ISD): A manufacturing paradigm comprising a method and system for real-time, closed-loop synthesis, supply, and consumption of precursors in IC manufacturing processes. In its simplest form, the system consists of a precursor synthesis chamber being physically interfaced with a thin film processing chamber, with precursor being synthesized on demand and supplied in a controlled fashion into the thin film processing chamber where it is consumed in the manufacturing process. This allows practical methods to employ highly reactive chemistry that otherwise could lead to explosive or highly toxic releases.
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The demand for surface modified and functionalized nanoparticles, nanopowders and nanocrystals is greater than ever. There is a continued effort to improve the performance of nanoparticles that are used in a variety of thermoplastic... more
The demand for surface modified and functionalized nanoparticles, nanopowders and nanocrystals is greater than ever. There is a continued effort to improve the performance of nanoparticles that are used in a variety of thermoplastic applications with a primary focus in biomedical, medical, ceramic, aerospace, electronic, and semiconductor. A new class of compounds has been synthesized to maximize bonding efficiency, while optimizing performance in an environmentally friendly manner. Cyclic Azasilanes can be reacted with a variety of hydroxyl laden nanoparticles through a ring-opening reaction that is thermodynamically driven without the formation of volatile byproducts. Cyclic Azasilanes offer a higher level of monolayer deposition compared to traditional organosilane and metal-organic chemistries. They find utility as coupling agents, surface modifiers and functionalizers.
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An overview of the evolution of siloxane polymers to meet the demands of silicone hydrogels is presented. Structural design of siloxane monomers and macromers as related to oxygen permeability, optical clarity, wettability, and mechanical... more
An overview of the evolution of siloxane polymers to meet the demands of silicone hydrogels is presented. Structural design of siloxane monomers and macromers as related to oxygen permeability, optical clarity, wettability, and mechanical properties is described.
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A study of hydrophilic silanes as a means to improve pigment wetting and dispersion in water-based color cosmetics including new amino acid modified silanes. Correlation of objective measurements to performance attributes are discussed.
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Siloxane macromers and macromolecular engineering for elastomer and dendrimer synthesis are presented.
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The synthesis and effectiveness of a fixed-bed hydroxylation catalyst complex that includes (i) a metal carbene catalyst, wherein the metal is platinum, and (ii) a catalyst support that includes one or more of silica, alumina and/or glass... more
The synthesis and effectiveness of a fixed-bed hydroxylation catalyst complex that includes (i) a metal carbene catalyst, wherein the metal is platinum, and (ii) a catalyst support that includes one or more of silica, alumina and/or glass is described. Hydrosilyation products using this chemistry have low color, high isomeric yield and allow recovery and re-use of active platinum.
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Thermoplastic composites have transformed everyday life. Portable tools, appliances and business machine housings in thousands of applications are the the design engineers materials of choice. This presentation overviews the innovations... more
Thermoplastic composites have transformed everyday life. Portable tools, appliances and business machine housings in thousands of applications are the the design engineers materials of choice. This presentation overviews the innovations made during the period of time in the '60s and '70s at LNP Engineering Plastics that spear-headed much of the development both technologically and by the cluster of companies started by former LNP employees. This presentation is a brief documentation of the challenges and development of engineering thermoplastic composites- including glass fiber and carbon fiber reinforcement systems with examples of applications in which there was early adoption of the new materials. It is a case history of business growth from concept to the creation of a multi-billion dollar industry.
Research Interests: Entrepreneurship, Business History, History of Science, Technological Innovation, Materials Science and Engineering, and 9 moreIndustrial Clusters, Strength of materials, polymer science and Engineering, Engineering Thermoplastics, History of Business Management, Business case study, Thermoplastic Composites, Entrepreneurial Hub, and Nylon Composites
Dipodal silanes have two silicon atoms which can bond covalently through oxane bridges to a surface. Dipodal silanes offer a distinctive advantage over conventional silanes, which possess only one silicon atom, in their ability to... more
Dipodal silanes have two silicon atoms which can bond covalently through oxane bridges to a surface. Dipodal silanes offer a distinctive advantage over conventional silanes, which possess only one silicon atom, in their ability to maintain the integrity of surface coatings in aggressive aqueous environments. This is important in applications in biotechnology, and particularly in separation science where long-term performance in aqueous environments is critical. Recently, dipodal silanes with "pendant" rather than "bridged" structures have been introduced. Bridged dipodal silanes substitute silicon atoms in alpha and omega positions of an organic moiety, while pendant dipodal silanes typically have silicon atoms separated by by two carbons and an organic moiety that in principle can extend outward from a modified surface. Significantly, in neutral, saline and highly acidic environments, pendant dipodal silanes clearly demonstrate improved resistance to hydrolysis compared to both conventional silanes and bridged dipodal silanes. New data shows that pendant dipodal silanes in which there is only one carbon separation between the silicon atoms have exceptional hydrolytic stability making them candidates for prep-scale chromatography where protocols require stability and reproducibilty.
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Self-assembled monolayers (SAMs) formed or modified by rapid "click" chemical reactions are receiving significant attention due to their demonstrated ability to promote or facilitate area-specific or area-selective deposition utilizing... more
Self-assembled monolayers (SAMs) formed or modified by rapid "click" chemical reactions are receiving significant attention due to their demonstrated ability to promote or facilitate area-specific or area-selective deposition utilizing processes that occur on time scales compatible with high-throughput manufacture and cyclic deposition schemes. By precision tailoring of the chemical structure of the SAM layer, the selectivity and speed of the reactions with both the underlying substrate and subsequent deposition cycles can be enhanced in order to provide rapid, selective processes with few or no chemical byproducts. In this work we demonstrate that cyclic azasilanes and cyclic thiasilanes can rapidly bond to the surface of hydroxyl-covered substrates in the vapor phase, with saturated coverage being reached in several seconds in a manufacturing-worthy atomic layer deposition tool. The effects of processing parameters, including pulse time, temperature, substrate type, and pre-treatment on the deposition profile, as well as the subsequent reactivity of cyclic azasilanes to further modify the chemical nature of the surface are discussed, with an emphasis on rapid "click" chemical processes compatible with high throughput. It was observed that on hydroxyl (OH)-terminated surfaces such as silicon native or thermal oxide the cyclic silanes reach a saturation point in approximately five seconds under typical ALD conditions over the temperature range of 30 °C to 300 °C, as determined by water contact angle and ellipsometry. The reactivity and selectivity of cyclic azasilanes to other oxide surfaces as well as non-oxides such as copper, silicon nitride, and HF-etched silicon will be discussed, as will process to remove azasilane monolayers after deposition.
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The identification of viable diffusion barrier/adhesion promoter material and associated deposition processes is a critical factor in the successful development of structurally and electrically reliable copper based metallization schemes.... more
The identification of viable diffusion barrier/adhesion promoter material and associated deposition processes is a critical factor in the successful development of structurally and electrically reliable copper based metallization schemes. As feature sizes continue shrinking, such materials are expected to delivery enhanced performance at increasingly thinner layers to allow maximum space utilization by the actual conductor. In this respect, Ta and W based binary and ternary nitrides present promising solutions in view of their hardness, chemical inertness, and thermal stability to high temperatures. Additionally, their availability in amorphous form provides the added benefit of inherent absence of grain boundaries, which usually serve as a primary diffusion path. This paper presents finds from the development of low-temperature (,350°C) CVD processes for the growth of ultrathin Ta, W, Ta-Si, and WSinitride layers for sub−0.18 micron device structures. These processes employ novel inorganic and metal-organic source precursors which allow for the in-situ, one-step, growth of binary and ternary nitrides from appropriate mixtures of the corresponding source precursors. Results will also be discussed from diffusion barrier studies which established performance metris for the applicability of such materials in copper interconnect technologies.
Research Interests:
Cyclic azasilanes have been synthesized for the purpose of developing coupling agents appropriate for a variety of nanotechnologies including surface modification of nanoparticles, nanocrystals, mesoporous materials and substrates. Cyclic... more
Cyclic azasilanes have been synthesized for the purpose of developing coupling agents appropriate for a variety of nanotechnologies including surface modification of nanoparticles, nanocrystals, mesoporous materials and substrates. Cyclic azasilanes contain cryptic amine functionality that can perform a coupling reaction with functional molecules after the surface-initiated ring-opening reaction, allowing for a one-pot self-assembly route on nanostructures. Activated silanes are blends of cyclic azasilanes with conventional silanes that provide high-speed reactivity induced by surfaces, unlike conventional silanes that require moisture for initiation. In epoxy resin systems, activated silanes with amine functionality give the benefits of moisture-free deposition, high speed reactivity, adhesion promotion, and high bond strengths between substrates. The kinetics and mechanism of cure, as well as mechanical bond strength between a variety of substrates will be investigated for a series of activated silane formulations.
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Advances for Silicon Chemistry are presented for 2004. Plenary and invited Lectures J.E. Mark Some Interesting Things about the Polysiloxanes; R.G. Nuzzo Micro, Nano, Macro: silico, Silicones and Soft-Lithography Off Road on the Road... more
Advances for Silicon Chemistry are presented for 2004. Plenary and invited Lectures
J.E. Mark Some Interesting Things about the Polysiloxanes; R.G. Nuzzo Micro, Nano, Macro: silico, Silicones and Soft-Lithography Off Road on the Road Map; I. Yilgor, E. Yilgor New Generation of Silicone-Urea Elastomers; M. J. Sailor Smart Dust: Photonic Crystals Derived from Nanocrystalline Porous Silicon; T. D. Tilley Participation of Ligand Alpha-Substituents in Bond Activations and Catalytic Transformations Involving Silicon; L. Rosenberg Catalytic Si-H Activation in the Synthesis and Modification of Organosilanes; I. N. Jung Dehydrogenative Double Silylation of Acetylenes; J. L. Leighton Straines Silacycles: A Powerful Platform for Asymmetric Reaction Design; U, Wiesner Polymer Approaches to Silicn Based Nanostructured Hybrid Materials; E. Liskola Molecular Control of Interface Chemistry by Atomic Layer Deposition (ALD); C. Strohmann About the Stereochemistry of Lithiated Silanes; V.S.-Y. Lin Gatekeeping Effect: Synthesis of Multi-functionalized Mesoporous Silica Nanospheres; R, West The Radical Chemistry of Stable Silylenes; R. Walsh What we have Learnes About the Stabilities Of Silarane; A. Sekiguchi Stable Disilyne with a Silicon-Silicon Triple Bond; S. Rubisztajn New Condensation Process Leading to the Formation of Siloxane Bonds; A. Basindale, P. Lickiss Colin Eaborn In Memorium
J.E. Mark Some Interesting Things about the Polysiloxanes; R.G. Nuzzo Micro, Nano, Macro: silico, Silicones and Soft-Lithography Off Road on the Road Map; I. Yilgor, E. Yilgor New Generation of Silicone-Urea Elastomers; M. J. Sailor Smart Dust: Photonic Crystals Derived from Nanocrystalline Porous Silicon; T. D. Tilley Participation of Ligand Alpha-Substituents in Bond Activations and Catalytic Transformations Involving Silicon; L. Rosenberg Catalytic Si-H Activation in the Synthesis and Modification of Organosilanes; I. N. Jung Dehydrogenative Double Silylation of Acetylenes; J. L. Leighton Straines Silacycles: A Powerful Platform for Asymmetric Reaction Design; U, Wiesner Polymer Approaches to Silicn Based Nanostructured Hybrid Materials; E. Liskola Molecular Control of Interface Chemistry by Atomic Layer Deposition (ALD); C. Strohmann About the Stereochemistry of Lithiated Silanes; V.S.-Y. Lin Gatekeeping Effect: Synthesis of Multi-functionalized Mesoporous Silica Nanospheres; R, West The Radical Chemistry of Stable Silylenes; R. Walsh What we have Learnes About the Stabilities Of Silarane; A. Sekiguchi Stable Disilyne with a Silicon-Silicon Triple Bond; S. Rubisztajn New Condensation Process Leading to the Formation of Siloxane Bonds; A. Basindale, P. Lickiss Colin Eaborn In Memorium
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DiEthicones maintain DiMethicones beneficial properties of excellent slip, spreading, gas permeability, and water proofness due to similar physical properties, yet DiEthicone possess greater compatibility with common suncare and cosmetic... more
DiEthicones maintain DiMethicones beneficial properties of excellent slip, spreading, gas permeability, and water proofness due to similar physical properties, yet DiEthicone possess greater compatibility with common suncare and cosmetic ingredients.
Research Interests:
Research Interests:
Low temperature growth of gallium nitride on silicon via vapor phase epitaxy was investigated. The use of different nitrogen and gallium sources was explored. The gallium nitride deposition process was optimized by varying surface... more
Low temperature growth of gallium nitride on silicon via vapor phase epitaxy was investigated. The use of different nitrogen and gallium sources was explored. The gallium nitride deposition process was optimized by varying surface preparation, seed and buffer layer growth, and annealing conditions. Films were extensively characterized via X-ray diffraction, Rutherford backscatter, atomic force microscopy, X-ray photoemission spectroscopy, and Auger electron spectroscopy. Optimized growth rates of 60-120 A/min were achieved at 0.8 torr pressure, with 1:1 gallium to nitride ratio to within 0.1%. Films were hexagonal and polycrystalline with 3 nitride bi-layer buffers, with annealing, allowed stoichiometric gallium nitride growth of up to 6000 A, but the temperatures used were not high enough to deposit epitaxial gallium nitride.
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Research Interests:
Research Interests:
Organic trihydridosilanes provide an elegant route for generating self-assembled monolayers (SAM)s by vapor phase transport on a variety of substrates. Under mild conditions, these precursors can be made to interact with a variety of... more
Organic trihydridosilanes provide an elegant route for generating self-assembled monolayers (SAM)s by vapor phase transport on a variety of substrates. Under mild conditions, these precursors can be made to interact with a variety of clean metal and hydrogenated metalloid surfaces such as Ti, Cu, and Si to form near-zero-thickness SAMs. These SAMs can be customized with specific functionality to activate or deactivate subsequent Co deposition on the underlying substrate, leading to area specific Co deposition.
Research Interests:
Low temperature growth of gallium nitride on silicon via vapor phase epitaxy was investigated. The use of different nitrogen and gallium sources was explored. The gallium nitride deposition process was optimized by varying surface... more
Low temperature growth of gallium nitride on silicon via vapor phase epitaxy was investigated. The use of different nitrogen and gallium sources was explored. The gallium nitride deposition process was optimized by varying surface preparation, seed and buffer layer growth, and annealing conditions. Films were extensively characterized via X-ray diffraction, Rutherford backscatter, atomic force microscopy, X-ray photoemission spectroscopy, and Auger electron spectroscopy. Optimized growth rates of 60-120 A/min were achieved at 0.8 torr pressure, with 1:1 gallium to nitride ratio to within 0.1%. Films were hexagonal and polycrystalline with 3 nitride bi-layer buffers, with annealing, allowed stoichiometric gallium nitride growth of up to 6000 A, but the temperatures used were not high enough to deposit epitaxial gallium nitride.
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SUMMARY Organic hydridosilanes can be grafted to hydrogen-terminated porous Si nanostructures without the use of a catalyst. The reaction proceeds efficiently with mild heating on the benchtop, and it shows little sensitivity to air or... more
SUMMARY
Organic hydridosilanes can be grafted to hydrogen-terminated porous Si nanostructures without the use of a catalyst. The reaction proceeds efficiently with mild heating on the benchtop, and it shows little sensitivity to air or water impurities. The resulting modified surfaces are stable to corrosive aqueous solutions and common organic solvents.
Organic hydridosilanes can be grafted to hydrogen-terminated porous Si nanostructures without the use of a catalyst. The reaction proceeds efficiently with mild heating on the benchtop, and it shows little sensitivity to air or water impurities. The resulting modified surfaces are stable to corrosive aqueous solutions and common organic solvents.
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Today's focus on hybrid organic-inorganic polymers is yielding many new materials. Although polydimethylsiloxanes (Dimethicones) and their many organic derivatives have been used extensively in the cosmetic industry, no polysiloxanes... more
Today's focus on hybrid organic-inorganic polymers is yielding many new materials. Although polydimethylsiloxanes (Dimethicones) and their many organic derivatives have been used extensively in the cosmetic industry, no polysiloxanes without methyl substitution have been developed for personal care. The Dimethicones are characterized by their ability to improve slip, increase lubricity, reduce tack, and impart water repellency in all types of cosmetic formulations. The insolubility of many surfactants, emollient oils, and waxes in the Dimethicone causes formulation difficulties and restricts the amount of Dimethicone that an be incorporated into a product.
Research Interests:
Research Interests:
The identification of viable diffusion barrier/adhesion promoter material and associated deposition processes is a critical factor in the successful development of structurally and electrically reliable copper-based metallization schemes.... more
The identification of viable diffusion barrier/adhesion promoter material and associated deposition processes is a critical factor in the successful development of structurally and electrically reliable copper-based metallization schemes. As feature sizes continue shrinking, such materials are expected to deliver enhanced performance at increasingly thinner layers to allow maximum space utilization by the actual conductor. In this respect, Ta and W based binary and ternary nitrides present promising solutions in view of their hardness, chemical inertness, and thermal stability to high temperatures. Additionally, their availability in amorphous form provides the added benefit of inherent absence of grain boundaries, which usually serve as a primary diffusion path. This paper presents the development of low temperature (350'C) CVD processes for the growth of ultrathin Ta, W, Ta-Si, and W-Si nitride layers for sub-0.18 micron device structures. These processes employ novel inorganic and metal-organic source precursors which allow for the in-situ, one-step, growth of binary and ternary nitrides from appropriate mixtures of the corresponding source precursors. Results will also be discussed from diffusion barrier studies which established performance metrics for the applicability of such materials in copper interconnect technologies. 499 Mat.
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Research Interests:
Low surface tension enables Vertasil® TM-L01 Limonenyl Trisiloxane and Caprylyl Methicone to spread easily on the skin. As a result, these fluids modify the feel and reduce the tack of materials such as natural butters and oils, as well... more
Low surface tension enables Vertasil® TM-L01 Limonenyl Trisiloxane and Caprylyl Methicone to spread easily on the skin. As a result, these fluids modify the feel and reduce the tack of materials such as natural butters and oils, as well as synthetic and petroleum based products. They exhibit the typical silicone " slip " and provide a non-greasy, silky soft after feel. An in-house study was conducted comparing the sensory experience of a 1:1 blend of Limonenyl Trisiloxane or Caprylyl Methicone in common cosmetic and personal care ingredients. Overall, 41% of panelists Limonenyl Trisiloxane and Caprylyl Methicone share similar solubility characteristics permitting compatibility with common raw materials including natural oils and waxes, hydrocarbons, esters, and UV absorbers. Both fluids can be used as co-solubilizers in formulations containing oil-insoluble fluids such as dimethicones.
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Exceptionally high mol. wt. polydimethylsiloxane elastomers were formed via step-growth polymn. of heterobifunctional siloxane macromonomers. These materials exhibited elastomeric behavior with no chem. crosslinking observable from... more
Exceptionally high mol. wt. polydimethylsiloxane elastomers were formed via step-growth polymn. of heterobifunctional siloxane macromonomers. These materials exhibited elastomeric behavior with no chem. crosslinking observable from advanced NMR1 DSC, and rheol. studies. Reinforcing the silicone elastomer with surface-passivated silica produced nanocomposites with tensile strengths up to 10 MPa and elongations approaching 5000% with good shape recovery. These ultra-high elongation silicone elastomers can be processed similar to conventional two-component platinum cure silicone RTVs. The synthesis and characterization of the siloxane macromonomers will be presented, as well as the mech. and phys. properties of the nanocomposites compared to conventional silicone elastomers.
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Research Interests:
New precursors for low temperature CVD of silicon nitride are described.
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While octadecylsilanes remain the dominant materials for preparation of bonded phases utilized in preparative chromatography, their stability is not robust in low pH phosphate buffer systems utilized for many biological separations.... more
While octadecylsilanes remain the dominant materials for preparation of bonded phases utilized in preparative chromatography, their stability is not robust in low pH phosphate buffer systems utilized for many biological separations. 1,2-bis(trichlorosilyl)octadecane, the first example of a pendant disposal silane has been evaluated in bonded phases at pH extremes.
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In the context of cosmetic formulation a material is considered occlusive if it acts as barrier to transepidermal moisture loss. Occlusive materials with optimum performance should have the ability to form continuous films with low water... more
In the context of cosmetic formulation a material is considered occlusive if it acts as barrier to transepidermal moisture loss. Occlusive materials with optimum performance should have the ability to form continuous films with low water permeability. A statistically significant decrease in TEWL was measured for the sites treated with PCS AM 114 (Myristyl Methicone and (Silethyl- phenylene)-(Dimethylsiloxane) Copolymer vs the bare skin control. No statistically signifi- cant effect was seen with Dimethicone/20 cs or Polydiethylsiloxane/20 cs compared to the bare skin.
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A new biomimetic approach toward surface hydrophilicity in which naturally occurring amino acids are modified, enabling their reaction with the surfaces of particles and pigments, has been developed . The treated particles and pigments... more
A new biomimetic approach toward surface hydrophilicity in which naturally occurring amino acids are modified, enabling their reaction with the surfaces of particles and pigments, has been developed . The treated particles and pigments represent a new class of water-dispersible materials suitable for cosmetic formulation. Biomimetic surface treatments which render surfaces hydrophobic have also been developed.
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Research Interests:
Synthesis and cosmetic applications of silane and siloxane modified Vitamin E derivatives are described.
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Abating bird-strikes on glass can be achieved with a non-reflective UV opaque coating based on new siliceous resins. Two hydroxy diphenylketone-containing organosilanes were synthesized and purified. The UV-absorbing and antireflective... more
Abating bird-strikes on glass can be achieved with a non-reflective UV opaque coating based on new siliceous resins. Two hydroxy diphenylketone-containing organosilanes were synthesized and purified. The UV-absorbing and antireflective organosilanes coatings for transparent or translucent coatings were formulated. The coating resin was applied to glass substrates by dipping or in the form of aerosol spray.
Vertasil ® TM-CBD (Trisiloxane functionalized Cannabidiol isolate) is an optimal CBD derivative to be used in silicone-based formulations due to an improved compatibility with silicones. Vertasil ® TM-CBD is a compatible CBD technology... more
Vertasil ® TM-CBD (Trisiloxane functionalized Cannabidiol isolate) is an optimal CBD derivative to be used in silicone-based formulations due to an improved compatibility with silicones. Vertasil ® TM-CBD is a compatible CBD technology for use with silicones and in silicone-based formulations. CONCLUSION BACKGROUND
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Organosilicon Chemistry: Chi-Long Lee; Dotsevi Y. Sogah; K. Peter C. Vollhardt; Richard P. Eckberg; Harald Rotzsche; John P. Oliver; Iwao Ojima; Robert Damrauer; Isaac Asimov
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Advances for Silicon Chemistry are presented for 2004. Plenary and invited Lectures J.E. Mark Some Interesting Things about the Polysiloxanes; R.G. Nuzzo Micro, Nano, Macro: silico, Silicones and Soft-Lithography Off Road on the Road... more
Advances for Silicon Chemistry are presented for 2004. Plenary and invited Lectures
J.E. Mark Some Interesting Things about the Polysiloxanes; R.G. Nuzzo Micro, Nano, Macro: silico, Silicones and Soft-Lithography Off Road on the Road Map; I. Yilgor, E. Yilgor New Generation of Silicone-Urea Elastomers; M. J. Sailor Smart Dust: Photonic Crystals Derived from Nanocrystalline Porous Silicon; T. D. Tilley Participation of Ligand Alpha-Substituents in Bond Activations and Catalytic Transformations Involving Silicon; L. Rosenberg Catalytic Si-H Activation in the Synthesis and Modification of Organosilanes; I. N. Jung Dehydrogenative Double Silylation of Acetylenes; J. L. Leighton Straines Silacycles: A Powerful Platform for Asymmetric Reaction Design; U, Wiesner Polymer Approaches to Silicn Based Nanostructured Hybrid Materials; E. Liskola Molecular Control of Interface Chemistry by Atomic Layer Deposition (ALD); C. Strohmann About the Stereochemistry of Lithiated Silanes; V.S.-Y. Lin Gatekeeping Effect: Synthesis of Multi-functionalized Mesoporous Silica Nanospheres; R, West The Radical Chemistry of Stable Silylenes; R. Walsh What we have Learnes About the Stabilities Of Silarane; A. Sekiguchi Stable Disilyne with a Silicon-Silicon Triple Bond; S. Rubisztajn New Condensation Process Leading to the Formation of Siloxane Bonds; A. Bassindale, P. Lickiss Colin Eaborn In Memorium
J.E. Mark Some Interesting Things about the Polysiloxanes; R.G. Nuzzo Micro, Nano, Macro: silico, Silicones and Soft-Lithography Off Road on the Road Map; I. Yilgor, E. Yilgor New Generation of Silicone-Urea Elastomers; M. J. Sailor Smart Dust: Photonic Crystals Derived from Nanocrystalline Porous Silicon; T. D. Tilley Participation of Ligand Alpha-Substituents in Bond Activations and Catalytic Transformations Involving Silicon; L. Rosenberg Catalytic Si-H Activation in the Synthesis and Modification of Organosilanes; I. N. Jung Dehydrogenative Double Silylation of Acetylenes; J. L. Leighton Straines Silacycles: A Powerful Platform for Asymmetric Reaction Design; U, Wiesner Polymer Approaches to Silicn Based Nanostructured Hybrid Materials; E. Liskola Molecular Control of Interface Chemistry by Atomic Layer Deposition (ALD); C. Strohmann About the Stereochemistry of Lithiated Silanes; V.S.-Y. Lin Gatekeeping Effect: Synthesis of Multi-functionalized Mesoporous Silica Nanospheres; R, West The Radical Chemistry of Stable Silylenes; R. Walsh What we have Learnes About the Stabilities Of Silarane; A. Sekiguchi Stable Disilyne with a Silicon-Silicon Triple Bond; S. Rubisztajn New Condensation Process Leading to the Formation of Siloxane Bonds; A. Bassindale, P. Lickiss Colin Eaborn In Memorium
Research Interests:
Silylene Transfer Reactions for Synthesis of Strained Alkenes, Keith Woerpel; Methylsilicones Pushed in Several Directions, Thomas McCarthy; N-Heterocyclic Silylenes, Matthias Dreiss; Surface Modification of Silicon Nanostructures;... more
Silylene Transfer Reactions for Synthesis of Strained Alkenes, Keith Woerpel; Methylsilicones Pushed in Several Directions, Thomas McCarthy; N-Heterocyclic Silylenes, Matthias Dreiss; Surface Modification of Silicon Nanostructures; Michael Sailor; Silicon-Hybrid Materials, Joseph Mabry; Silicon Nanocrystal Assemblies; Brian Korgel; New Materials Properties Through a Silicone Blend Strategy, Francois Ganachaud; New Methods for Tethered Carbonyl Silylations, Gregory O'Neil; Advances in Preparation of Organosilanes Using Palladium Catalysis, Donald Watson; Synthesis and Applications of Silicone Copolymers, Ramesh Kumar; Towards Controlled Synthesis and Characterization of Complex Silicone Architectures; Use of Nanocatalysis in the Direct Synthesis of Methylchlorosilanes and Alkoxysilanes; Kendrick Lewis; Material Behavior of Self-Aligned Silicon Carbide Nanowire Arrays; Spyros Gallis; Cyclohexasilane, A Source of Quantum Dots, Nanowires, Philip Boudjouk; Mechanism of Oligomerization of N-Heterocyclic Silylenes, Andrey Rogachev; The Addition of Isocyanides to Disilenes, Kim Baines; Oscilations in the mSR Spectra of Muionated Organosilyl Free Radicals, Kerim Samedov; Electrophilic Substitution on Phenylsilsesquioxanes, Richard Laine; Synthesis and Reaction of Janus Prisms, Masafumi Unno
Research Interests:
Silylene Transfer Reactions for Synthesis of Strained Alkenes, Keith Woerpel; Methylsilicones Pushed in Several Directions, Thomas McCarthy; N-Heterocyclic Silylenes, Matthias Dreiss; Surface Modification of Silicon Nanostructures;... more
Silylene Transfer Reactions for Synthesis of Strained Alkenes, Keith Woerpel; Methylsilicones Pushed in Several Directions, Thomas McCarthy; N-Heterocyclic Silylenes, Matthias Dreiss; Surface Modification of Silicon Nanostructures; Michael Sailor; Silicon-Hybrid Materials, Joseph Mabry; Silicon Nanocrystal Assemblies; Brian Korgel; New Materials Properties Through a Silicone Blend Strategy, Francois Ganachaud; New Methods for Tethered Carbonyl Silylations, Gregory O'Neil; Advances in Preparation of Organosilanes Using Palladium Catalysis, Donald Watson; Synthesis and Applications of Silicone Copolymers, Ramesh Kumar; Towards Controlled Synthesis and Characterization of Complex Silicone Architectures; Use of Nanocatalysis in the Direct Synthesis of Methylchlorosilanes and Alkoxysilanes; Kendrick Lewis; Material Behavior of Self-Aligned Silicon Carbide Nanowire Arrays; Spyros Gallis; Cyclohexasilane, A Source of Quantum Dots, Nanowires, Philip Boudjouk; Mechanism of Oligomerization of N-Heterocyclic Silylenes, Andrey Rogachev; The Addition of Isocyanides to Disilenes, Kim Baines; Oscilations in the mSR Spectra of Muionated Organosilyl Free Radicals, Kerim Samedov; Electrophilic Substitution on Phenylsilsesquioxanes, Richard Laine; Synthesis and Reaction of Janus Prisms, Masafumi Unno; Investigation of Hydrogen-Bonding Ability of 1,3-Disiloxanediols and Polyhedral Oligomeric Silsesquioxanes with Applications for Catalysis, Kayla Diemoz; Evolution of the Photoluminescence Properties of Colloidal Silicon Nanoparticles over Time and with Environmental Changes, Andrea Goforth; Novel Synthesis of Spirocyclic Silicones and Subsequent Branching, Jennifer Morgan; Study of Polydimethylsiloxane (PDMS) Elastomer Generated by g Irradiation: Correlation Between Properties (Thermal and Mechanical) and Structure (Crosslink Density Value), M. Meléndez-Zamudio;
This volume contains 65 papers from a symposium entitled "Chemical Aspects of Electronic Ceramics Processing," held over four days at the 1997 MRS Fall Meeting in Boston. The common themes in all of the research presented in this volume... more
This volume contains 65 papers from a symposium entitled "Chemical Aspects of Electronic Ceramics Processing," held over four days at the 1997 MRS Fall Meeting in Boston. The common themes in all of the research presented in this volume are the creative use of chemistry principles for ceramic fabrication and a multidisciplinary approach to materials research. Inorganic chemistry, solid-state chemistry, chemical engineering, materials science and engineering, and electrical engineering have all been skillfully combined to produce materials which will play an increasingly more important part in our lives. As in prior years, chemical vapor deposition (CVD) continues to be a popular area of research and was the subject of approximately half of the papers in this volume. Particularly "hot" areas of research are new and improved precursors, delivery systems for low-vapor pressure precursors, and improved processing and materials properties. Papers are evenly divided between oxide ceramics and non- oxide ceramics.
Research Interests:
An overview of silane and silicone chemistry in 15 full chapter reviews. A register of over 2500 silicon compounds with physical properties, chemical structures and application data is provided. 608 pages + inserts. Review Chapters: An... more
An overview of silane and silicone chemistry in 15 full chapter reviews. A register of over 2500 silicon compounds with physical properties, chemical structures and application data is provided. 608 pages + inserts. Review Chapters: An Organosilicon Chemistry Primer; Naming Silicon Compound; Polysilanes; Silicon-Based Anion Relay Chemistry; Bioactive Organosilanes;Cross-Couling of Silanols and Silanolates; Silicon-Based Blocking Agents; Silanes and Surfaces; Bond Dissociation Energies of Organosilicon Compounds; Si NMR: Practical Aspects; Infrared Analysis of Organosilicon Compounds; Ring-Opening Polymerization of Cyclosiloxanes; Telechelic Siloxane Oligomers; Silicones: Stable, Inert Media; Reactive Silicones and Elastomer Formulation. Detailed and referenced properties for ~2500 Silicon Compounds are presented. 608 pages
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Metal-Organic Materials Science Articles and Registry of Compounds TOC: Crystallography; Lattices; Point Defects; Transition Metal Oxides; Metal Alkoxides and Diketonates; Some Synthetic Applications of Organoaluminum Compounds; Germanium... more
Metal-Organic Materials Science Articles and Registry of Compounds TOC: Crystallography; Lattices; Point Defects; Transition Metal Oxides; Metal Alkoxides and Diketonates; Some Synthetic Applications of Organoaluminum Compounds; Germanium Compounds: Chemistry and Applications; Industrial applications of Organotin Compounds; Catalytic Applications of Tin Compounds; Applications of Metal-Organic Titanium Compounds; Zirconium Compounds and Complexes in Organic Synthesis; Metal Trifluoromethanesulfonates; Sol-Gel Chemistry; Analytical Methods.
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An overview of surface modification with silicon based coupling agents.
Research Interests:
Silicon Chemistry Primer; S.S. Washburne Expedited Organic Synthesis; T.J. Barton Reactive Intermediates in Organosilicon Chemistry; P.F. Hudrlik Some Applications of Organosilicon Compounds; B. Arkles Techniques for Silylation
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Research Interests:
An overview of silane and silicone chemistry in 15 full chapter reviews. A register of over 2500 silicon compounds with physical properties, chemical structures and application data is provided. 608 pages + inserts. Review Chapters: An... more
An overview of silane and silicone chemistry in 15 full chapter reviews. A register of over 2500 silicon compounds with physical properties, chemical structures and application data is provided. 608 pages + inserts. Review Chapters: An Organosilicon Chemistry Primer; Naming Silicon Compound; Polysilanes; Silicon-Based Anion Relay Chemistry; Bioactive Organosilanes;Cross-Couling of Silanols and Silanolates; Silicon-Based Blocking Agents; Silanes and Surfaces; Bond Dissociation Energies of Organosilicon Compounds; Si NMR: Practical Aspects; Infrared Analysis of Organosilicon Compounds; Ring-Opening Polymerization of Cyclosiloxanes; Telechelic Siloxane Oligomers; Silicones: Stable, Inert Media; Reactive Silicones and Elastomer Formulation. Detailed and referenced properties for ~2500 Silicon Compounds are presented.
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Depiction of the applications of the elements with atomic weights etc.