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Microelectronic Devices (microelectronic + device)
Selected AbstractsImproved resolution with microchip-based enhanced field inversion electrophoresisELECTROPHORESIS, Issue 11 2003Christopher J. Backhouse Abstract We present an improvement of the field inversion electrophoresis (FIE) method in which the passage of sample such as DNA back and forth within a short length of a microchannel can provide a similar resolution to that of a significantly longer microchannel. In constant field FIE the application of an alternating potential (e.g., +/, V) over short periods of time (e.g., several Hz) can provide enhanced separations of DNA fragments. In contrast, the present method consists of a series of separations, each of much longer duration, under high and low fields in such a way that the resolution is enhanced. This method is readily modeled and allows improved resolution to be obtained from extremely short microchannels (e.g., 8 mm) while requiring relatively low applied voltages (e.g., less than 600 V). An additional advantage is that this method can allow for the same equipment to be used in a rapid, low-resolution mode or in a slower, high-resolution mode through what might be referred to as an automated "zoom" capability. We believe that this method may facilitate the integration of microfluidic devices and microelectronic devices by allowing these devices to be of a similar small scale (< 1 cm). [source] Functional Chromium Wheel-Based Hybrid Organic,Inorganic Materials for Dielectric ApplicationsADVANCED FUNCTIONAL MATERIALS, Issue 20 2009Vito Di Noto Abstract The first example of organic,inorganic hybrid materials based on the embedding of a chromium,nickel wheel cluster {[(n-C3H7)2NH2]- [Cr7NiF8(O2C4H5)16]} (Cr7Ni) into poly(methyl methacrylate) (PMMA) and the characterization of the dielectric properties of the obtained material is described. By an optimized copolymerization of the methacrylate-functionalized chromium,nickel wheel with methyl methacrylate in a cluster/monomer 1:200 molar mixture, a homogeneous hybrid material CrNi_MMA200 is obtained. The electrical responses of the non-doped PMMA and of the hybrid material were studied by broadband dielectric spectroscopy (BDS) from 0.01,Hz to 10,MHz and over the temperature range of 5,115,°C. The permittivity profiles reveal two relaxation peaks in the materials, which correspond to the , and , relaxation modes of the PMMA matrix. The position of these modes shifts toward higher frequencies as temperature increases. BDS is a powerful tool revealing the intimate miscibility of the various components of the hybrid material, thus indicating that, on a molecular scale, the material proposed is a homogeneous system. Finally, a value of the dielectric constant of 2.9 at 25,°C and 1,kHz is determined. This value is noticeably lower than the value of 3.2 obtained for pristine PMMA prepared following the same synthesis protocol. Thus, these results classify the hybrid CrNi_MMA200 as an appealing starting material for the development of dielectric polymeric layers for the development of innovative capacitors, transistors, and other microelectronic devices. The vibrational properties of the hybrid materials are investigated by Fourier-transform infrared (FT-IR) and Raman spectroscopy, whereas the thermal behavior is analyzed by thermogravimetric analysis (TGA). Swelling experiments are used to qualitatively evaluate the crosslinking density of the hybrid materials. The integrity of the wheels once embedded in the macromolecular backbone is confirmed by extended X-ray absorption fine structure (EXAFS) and electron spin resonance (EPR) spectroscopic measurements. [source] Polyethersulfone-epoxy terminated materials as thermosetting resins for microelectronic devicesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2009Emilio Scamporrino Abstract A totally aromatic polyether/sulfone resin (PES-E) was synthesized and tested as an insulating glue in the construction of a Chip-on-Chip (CoC) device. PES-E, essentially constituted of open-chain macromolecules of low molecular mass (Mn of about 3000 Da) with hydroxy and/or epoxy end-groups, has a glass transition temperature of about 150 °C and is subject to crosslinking at temperatures higher than 320 °C. A CoC device was assembled using a five-step process by interposing a layer of PES-E between two chips. After curing, SEM cross section images showed a homogeneous crosslinked resin layer well stuck (flick and shear tests) to both chips. The chemical structure of the chains and the hydroxy/epoxy end-groups ratio were optimized to obtain a crosslinked material with good adhesion and sufficient flexibility to avoid cracking during assembly and use. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5682,5689, 2009 [source] Polymer-Based Rectifying Diodes on a Glass Substrate Fabricated by Ink-Jet PrintingMACROMOLECULAR RAPID COMMUNICATIONS, Issue 4 2005Yi Liu Abstract Summary: The fabrication of polymer diodes on a glass substrate by an ink-jet printing technique is reported. Both an n-type semiconductive polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-(1-cyanovinylene)phenylene] (CN-PPV), and a p-type semiconductive polymer, polypyrrole (PPy) or poly(3,4-ethylenedioxythiophene) (PEDOT), were printed through a piezoelectric ink-jet printer. The printed CN-PPV/PPy and CN-PPV/PEDOT diodes showed good rectifying characteristics. These results indicate the potential of the low-cost ink-jet printing technique to produce polymer microelectronic devices and circuits. Schematic diagram of the printed polymer diode [source] Detection of volatile organic compounds using a polythiophene derivativePHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 7 2010V. C. Gonçalves Abstract Conjugated polymers have been subject of great interest in the recent literature from both fundamental point of view and applied science perspective. Among the several types of conjugated polymers used in recent investigations, polythiophene and its derivatives have attracted considerable attention over the past 20,years due to their high mobility and other remarkable solid-state properties. They have potential applications in many fields, such as microelectronic devices, catalysts, organic field-effect transistors, chemical sensors, and biosensors. They have been studied as gas and volatile organic compounds (VOCs) sensors using different principles or transduction techniques, such as optical absorption, conductivity, and capacitance measurements. In this work, we report on the fabrication of gas sensors based on a conducting polymer on an interdigitated gold electrode. We use as active layer of the sensor a polythiophene derivative: poly (3-hexylthiophene) (P3HT) and analyzed its conductivity as response for exposure to dynamic flow of saturated vapors of six VOCs [n -hexane, toluene, chloroform, dichloromethane, methanol, and tetrahydrofuran (THF)]. Different responses were obtained upon exposure to all VOCs, THF gave the higher response while methanol the lower response. The influence of moisture on the measurements was also evaluated. [source] Control of composition and structure of ferroelectric oxide thin films grown by pulsed laser depositionPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2008Maryline Guilloux-Viry Abstract SrBi2Nb2O9 and KTa1,xNbxO3 high quality thin films were grown by pulsed laser deposition. An accurate optimization of deposition conditions is a prerequisite for the control of composition, mainly according to the high volatility of Bi and K. In order to take benefit of the ferroelectric characteristics for new microelectronic devices, thin films were epitaxially grown on various substrates and seed layers adapted to application requirements. For that purpose metal electrodes and ferroelectric oxides were associated in a planar capacitor geometry or in a coplanar configuration depending on the targeted applications. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||