A5064788120- Graphene research and applications
- Semiconductor materials and devices
- Asthma and respiratory diseases
- Silicon Carbide Semiconductor Technologies
- 2D Materials and Applications
- Respiratory and Cough-Related Research
- GaN-based semiconductor devices and materials
- Acoustic Wave Resonator Technologies
- Protein Kinase Regulation and GTPase Signaling
- Ferroelectric and Piezoelectric Materials
- Chemical Synthesis and Analysis
- Chalcogenide Semiconductor Thin Films
- Diamond and Carbon-based Materials Research
- Advanced Semiconductor Detectors and Materials
- Ga2O3 and related materials
- Quantum Dots Synthesis And Properties
- Metal and Thin Film Mechanics
- Cardiovascular Function and Risk Factors
- Synthesis of Organic Compounds
- Superconductivity in MgB2 and Alloys
- ZnO doping and properties
- Microwave Dielectric Ceramics Synthesis
- Peptidase Inhibition and Analysis
- Neuroscience of respiration and sleep
- Neuropeptides and Animal Physiology
Applied Research Laboratory at Penn State
2005-2024
Pennsylvania State University
2012-2024
Freeport-McMoRan (United States)
2004-2024
Applied Research (United States)
2000-2023
Roche (United States)
2023
Applied Research Laboratory at the University of Hawai‘i
1991-2022
Park University
2020-2021
Penn State Milton S. Hershey Medical Center
2021
Washington University in St. Louis
2015
Illinois State University
1999-2011
We present a robust method for forming high quality ohmic contacts to graphene, which improves the contact resistance by nearly 6000 times compared untreated metal/graphene interfaces. The optimal specific treated Ti/Au is found average <10−7 Ω cm2. Additionally, we examine Al/Au, Ti/Au, Ni/Au, Cu/Au, Pt/Au, and Pd/Au metallizations find that most result in similar resistances this work regardless of function difference between graphene metal overlayer. results presented serve as...
We report a direct correlation between carrier mobility and Raman topography of epitaxial graphene (EG) grown on silicon carbide (SiC). show the Hall material Si-face SiC [SiC(0001)] is not only highly dependent thickness uniformity but also monolayer strain uniformity. Only when both are uniform over significant fraction (> 40%) device active area does exceed 1000 cm2/V-s. Additionally, we achieve high (18,100 cm2/V-s at room temperature) C-face [SiC(000-1)] that depends strongly layer...
A promising route for the synthesis of large-area graphene, suitable standard device fabrication techniques, is sublimation silicon from carbide at elevated temperatures (>1200 °C). Previous reports suggest that graphene nucleates along (11̅0n) plane, known as terrace step edges, on surface. However, to date, a fundamental understanding nucleation lacking. We provide first direct evidence epitaxial occurs plane and show nucleated quality improves temperature increased. Additionally, we find...
We present a novel method for the direct metal-free growth of graphene on sapphire that yields high quality films comparable to grown SiC by sublimation. Graphene is synthesized via simple decomposition methane at 1425-1600 °C. Film was found be strong function temperature. The thickness, structure, interface characteristics, and electrical transport properties were characterized in order understand utility this material electronic devices. strain relieved, with no evidence an interfacial...
We directly demonstrate the importance of buffer elimination at graphene/SiC(0001) interface for high frequency applications. Upon successful elimination, carrier mobility increases from an average 800 cm(2)/(V s) to >2000 s). Additionally, graphene transistor current saturation 750 >1300 mA/mm, and transconductance improves 175 mS/mm >400 mS. Finally, we report a 10× improvement in extrinsic gain response transistors with optimal current-gain cutoff frequencies 24 GHz.
Hexagonal boron nitride (h-BN) is a promising dielectric material for graphene-based electronic devices. Here we investigate the potential of h-BN gate dielectrics, grown by chemical vapor deposition (CVD), integration with quasi-freestanding epitaxial graphene (QFEG). We discuss large scale growth on copper foil via catalytic thermal CVD process and subsequent transfer to 75 mm QFEG wafer. X-ray photoelectron spectroscopy (XPS) measurements confirm absence h-BN/graphitic domains indicate...
Radio frequency (RF) microelectromechanical systems (MEMS) based on Al1–xScxN are replacing AlN-based devices because of their higher achievable bandwidths, suitable for the fifth-generation (5G) mobile network. However, overheating film bulk acoustic resonators (FBARs) used in RF MEMS filters limits power handling and thus phone's ability to operate an increasingly congested environment while maintaining its maximum data transmission rate. In this work, ramifications tailoring piezoelectric...
β-phase gallium oxide (Ga2O3) is an emerging ultrawide bandgap (UWBG) semiconductor (EG ∼ 4.8 eV), which promises generational improvements in the performance and manufacturing cost over today's commercial wide power electronics based on GaN SiC. However, overheating has been identified as a major bottleneck to commercialization of Ga2O3 device technologies. In this work, novel Ga2O3/4H-SiC composite wafer with high heat transfer epi-ready surface finish developed using fusion-bonding...
ICI 204,219 (4-(5-cyclopentyloxycarbonylamino-1-methylindol-3-ylmethyl)-3-methoxy-N-o-tolylsulfonylbenzamide) was designed as a peptide leukotriene (LT) antagonist. The compound is competitive antagonist of LTD4- and LTE4-induced contraction guinea pig lung tracheal parenchymal strips with an apparent negative log molar dissociation constant (KB) approximately 9.6. did not antagonize LTC4-induced contractions trachea when the metabolism LTC4 to LTD4 and, subsequently, LTE4 inhibited....
The effect of the leukotriene (LT) antagonist, FPL55712, on contractile activity peptide leukotrienes was evaluated in presence and absence enzyme inhibitors metabolism. L-Cysteine, an inhibitor aminopeptidase, prevents formation LTE4 from LTD4 LTC4. L-Serine borate, gamma-glutamyl transpeptidase conversion LTC4 to LTD4. L-Cysteine (3mM) enhanced borate (45 mM) increased selectively FPL55712 (10 microM) antagonized LTC4, inhibitors. In L-serine (10-30 failed antagonize but did LTE4. However,...
We present the integration of epitaxial graphene with thin film dielectric materials for purpose transistor development. The impact on structural and electronic properties following deposition Al2O3, HfO2, TiO2, Ta2O5 varies based choice parameters. Each requires use a nucleation layer to ensure uniform, continuous coverage surface. Graphene quality degrades most severely Ta2O5, while if TiO2 appears improve carrier mobility. Finally, we discuss potential stack engineering improved performance.
ICI 198,615 is a representative compound from new class of peptide leukotriene (LT) receptor antagonists. In isolated guinea pig trachea and parenchymal lung strips, demonstrated competitive antagonism the contractile activity LTD4 LTE4 with pA2 values 10.1 to 9.5, respectively. The also appeared antagonize LTC4 in trachea; however, presence an inhibitor metabolism LTD4, 198, 615 provided pKB value 5.3, indicating weak at receptor. was potent antagonist human bronchi pulmonary veins pKa 9.75...
We explore the effect of high-κ dielectric seed layer and overlayer on carrier transport in epitaxial graphene. introduce a novel seeding technique for depositing dielectrics by atomic deposition that utilizes direct layers can lead to an increase Hall mobility up 70% from as-grown. Additionally, seeded are shown produce superior transistor performance relative low-κ presence heterogeneous seed/overlayer structures is found be detrimental performance, reducing effective 30–40%. The...
Operation at temperatures well above ambient is desired for applications such as smart structures integrated within aircraft and space vehicles. Piezoelectric yttrium calcium oxyborate single crystal YCa4O(BO3)3 (YCOB) was found to exhibit no phase transition until its melting temperature around ∼1500°C. The characteristics of the resonance frequency, electromechanical coupling, dielectric permittivity were studied in range 30–950°C different orientations. electrical resistivity 800°C be...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEvolution of a series peptidoleukotriene antagonists: synthesis and structure-activity relationships 1,6-disubstituted indoles indazolesFrederick J. Brown, Ying K. Yee, Laura A. Cronk, Kevin C. Hebbel, Robert D. Krell, David W. SnyderCite this: Med. Chem. 1990, 33, 6, 1771–1781Publication Date (Print):June 1, 1990Publication History Published online1 May 2002Published inissue 1 June 1990https://doi.org/10.1021/jm00168a036RIGHTS & PERMISSIONSArticle...
Heteroepitaxy of β-phase gallium oxide (β-Ga2O3) thin films on foreign substrates shows promise for the development next-generation deep ultraviolet solar blind photodetectors and power electronic devices. In this work, influences film thickness crystallinity thermal conductivity (2̅01)-oriented β-Ga2O3 heteroepitaxial were investigated. Unintentionally doped grown c-plane sapphire with off-axis angles 0° 6° toward ⟨112̅0⟩ via metal–organic vapor phase epitaxy (MOVPE) low-pressure chemical...
Abstract We report polycrystalline diamond epitaxial growth on β -Ga 2 O 3 for device-level thermal management. focused establishing conditions accompanying the study of various nucleation strategies. A window was identified, yielding uniform-coalesced films while maintaining interface smoothness. In this first demonstration , a conductivity 110 ± 33 W m −1 K and diamond/ boundary resistance 30.2 1.8 G were measured. The film stress managed by optimization techniques preventing delamination...
The preceding papers of this series detail the development functionalized indole-3-acetamides as inhibitors hnps-PLA2. We describe here extension structure−activity relationship to include a indole-3-glyoxamide derivatives. Functionalized indole-3-glyoxamides with an acidic substituent appended 4- or 5-position indole ring were prepared and tested It was found that 4-oxyacetic acid had optimal inhibitory activity. These exhibited improvement in potency over best indole-3-acetamides, LY315920...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEvolution of a series peptidoleukotriene antagonists: synthesis and structure/activity relationships 1,3,5-substituted indoles indazolesVictor G. Matassa, Thomas P. Maduskuie Jr., Howard S. Shapiro, Barrie Hesp, David W. Snyder, Aharony, Robert D. Krell, Richard A. KeithCite this: J. Med. Chem. 1990, 33, 6, 1781–1790Publication Date (Print):June 1, 1990Publication History Published online1 May 2002Published inissue 1 June...