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Reactive Ion Etching (reactive + ion_etching)
Selected AbstractsUltra-miniature optical fiber pressure sensor with a sleeve for catheter insertionELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 8 2009Masato Shimada Abstract A diaphragm-type optical fiber pressure sensor, which has a sleeve for fiber insertion, is proposed, and the fundamental characteristics of this sensor are demonstrated. The sleeve structure is fabricated by DRIE (Deep Reactive Ion Etching). The diaphragm with a sleeve is suitable for highly reliable and easy bonding between the sleeve and the optical fiber. The light intensity change detection by the Fabry,Perot interferometer based on the pressure is increased by the improved DRIE method. The mass production method of the developed diaphragm will be useful for creating a low-cost pressure sensor. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(8): 36,42, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10044 [source] Fabrication of a Superhydrophobic Surface from a Smectic Liquid-Crystal Defect ArrayADVANCED FUNCTIONAL MATERIALS, Issue 18 2009Yun Ho Kim Abstract A novel fabrication method is developed for the preparation of superhydrophobic surfaces. The procedure uses focal conic structures of semi-fluorinated smectic liquid crystals (LCs) whose periodic toric focal conic domains (TFCDs) are prepared on a surface modified substrate. Reactive ion etching (RIE) on the periodic TFCD surface leads to a superhydrophobic surface with a water contact angle of ,160° and a sliding angle of ,2° for a 10,µL water droplet. The results show that this phenomenon is due to the development of a dual-scale surface roughness arising from the nanoscale protuberance caused by applying the RIE process to the top of the microscale TFCD arrays. The unique surface behavior is further verified by demonstrating that RIE on a flat lamellar liquid crystal film, in which the director is aligned parallel with surface, results in a relatively low hydrophobicity as compared to when periodic TFCDs are subjected to REI. The observations made in this publication suggest that a new approach exists for selecting potential candidates of superhydrophic surface formation based on spontaneous self-assembly in smectic liquid-crystalline materials. [source] Reactive ion etching of dielectrics and silicon for photovoltaic applicationsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 7 2006Prakash N. K. Deenapanray Abstract This paper investigates the reactive ion etching of SiO2, Si3N4, and Si using CHF3/O2 plasma. In particular, we have characterized the time and rf power dependence of the carrier lifetimes in n- and p-type FZ Si. The time dependence of reactive ion etching (RIE) at different rf powers provide insight into the two competing processes of damage accumulation and damage removal in the near-surface region of the Si during plasma etching. The carrier lifetime, measured using the quasi-steady-state photoconductance (QSSPC) technique, has a quadratic dependence on the rf power, which can be related to changes in the dc self-bias generated by the plasma at different rf powers. The change in carrier lifetime is similar in both n- and p-type Si of the same doping concentration. Using this fact, together with the electronic properties of defects obtained by deep level transient spectroscopy (DLTS), we have modeled the injection-dependence of the measured carrier lifetimes using the Shockley,Read,Hall model. The isochronal annealing behavior of plasma etched Si has also been studied. Copyright © 2006 John Wiley & Sons, Ltd. [source] Fine surface processing of LiNbO3 single crystals by maskless etching using NF3 system gas plasma RIEELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 2 2010Teruaki Omata Abstract The possibility of deep etching by plasma reactive ion etching (RIE) without an etching-mask (maskless) for ,Z and +Z parts formed on the same surface of a partially polarization reversed LiNbO3 single crystal polarized in the direction of the c -axis is investigated. A NF3/H2 gas mixture was used. The etching rates and depths and the profiles of the etched surfaces were evaluated by atomic force microscopy (AFM) and optical microscopy. The etching rate for the ,Z surface was larger than that for the +Z surface. Extension of the +Z domain by partial polarization reversal was observed. Applying the high voltage quickly for partial polarization reversal, the area of the +Z domain was extended compared with the result obtained by applying the voltage slowly. An apparent step at the boundary between ,Z and +Z parts formed on the same surface was observed. Using a NF3/H2 gas mixture, the segments were removed efficiently. It is concluded that RIE etching using a NF3/H2 gas mixture is suitable for processing of LiNbO3 crystal surfaces without an etching mask, in contrast with a CF4/H2 gas mixture. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(2): 39,49, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10168 [source] A Three-Dimensional and Sensitive Bioassay Based on Nanostructured Quartz Combined with Viral NanoparticlesADVANCED FUNCTIONAL MATERIALS, Issue 12 2010Jong-Hwan Lee Abstract An effective mask-free method for fabricating high-aspect-ratio pillarlike nanostructures over a large area of a quartz surface via a simple O2 and CF4 two-step reactive ion etching (RIE) procedure is developed. The nanostructured quartz surfaces are successfully combined with the engineered viral particles derived from hepatitis B virus capsid, yielding a novel 3D assay system with attomolar sensitivity, which has great potential for use in sensitive and early detection of various disease markers. [source] Silicon Microstructures: Detachment Lithography of Photosensitive Polymers: A Route to Fabricating Three-Dimensional Structures (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 2 2010Mater. The scanning electron microscope image featured on the front cover shows a three-dimensional polydimethylsiloxane (PDMS) molded film bonded on a glass rod. Multilevel silicon structures used to mold the PDMS film were fabricated from successive steps of detachment lithography of photoresist films, which are patterned with lithography and reactive ion etching, as reported by J. Yeom and M. A. Shannon on page 289. The smallest feature on the pyramid is 2 µm in diameter. [source] Polystyrene Arrays: Non-Close-Packed Crystals from Self-Assembled Polystyrene Spheres by Isotropic Plasma Etching: Adding Flexibility to Colloid Lithography (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 20 2009Mater. Hexagonally ordered arrays of non-close-packed spherical polystyrene (PS) particles are prepared by A. Plettl et al. on page 3279, and exhibit precisely controlled diameters and interparticle distances. An isotropic low-temperature plasma-etching process is applied to extended monolayers of PS colloids deposited onto hydrophilic silicon. These non-close-packed PS arrays are used as masks for the fabrication of arrays of cylindrical nanopores by reactive ion etching. [source] Self-Assembled Nanoscale Ring Arrays from a Polystyrene- b -polyferrocenylsilane- b -poly(2-vinylpyridine)Triblock Terpolymer Thin FilmADVANCED MATERIALS, Issue 37 2009Vivian P. Chuang Hollow ring arrays with an outer and inner diameter of 33 and 11,nm, respectively, are formed from a thin film of poly-(styrene- b -ferrocenylethylmethylsilane- b -2-vinyl pyridine) (PS- b -PFS- b -P2VP) triblock terpolymer with a core/shell cylindrical morphology. The PS minority block forms a core surrounded by a PFS shell in a P2VP matrix; the core/shell structure is oriented perpendicularly to the film surface. The PS core and P2VP matrix blocks are partly removed using oxygen reactive ion etching, leaving ring patterns made from oxidized PFS. [source] Vertically aligned diamond nanowires: Fabrication, characterization, and application for DNA sensingPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 9 2009Nianjun Yang Abstract In this review, we introduce a novel procedure to fabricate vertically aligned diamond nanowires with controlled geometrical properties like length and distance between wires by use of nanodiamond particles as a hard mask and by use of reactive ion etching. We summarize the characterizations of nanowires by atomic force microscopy and scanning tunneling microscopy as well as electrochemical techniques. In the last section, we show biofunctionalization of nucleic acid molecules on diamond nanowires using electrochemically bond nitrophenyl molecules as linker for deoxyribonucleic acid (DNA) sensing. The tip biofunctionalization and performance of as-prepared DNA sensors are discussed in detail. [source] Selective patterning of covalent molecular grafting on doped amorphous silicon templatesPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3-4 2010Hussein Sabbah Abstract Linear alkene molecules have been covalently immobilized on amorphous silicon surfaces. The larger thermal reactivity of n+ -doped vs. nominally undoped a-Si:H surfaces towards perfluorodecene (PFD) molecules in the gas phase has been exploited to investigate a selective patterning of molecular grafting on a previously defined template of doped / undoped regions. PFD has been chosen to obtain hydrophobic monomolecular layers with fluorine labelling, useful for photoelectron spectroscopy (XPS) and NanoSIMS imaging. The template was obtained by growing undoped a-Si:H on top of n+ a-Si-H, and defining 40 ,m-edge patterns of undoped a-Si:H by reactive ion etching in a (CF4, O2) mixture. After native oxide removal, the patterned surface was exposed to PFD at 230 °C. NanoSIMS images, taken at increasing Cs+ irradiation doses, show the expected 19F and 28Si contrast on as-grafted surfaces; this contrast disappears after ,340 seconds Cs+ irradiation, corresponding to the desorption of the PFD monomolecular layer. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Improved optical properties using self-organized GaN nanotip structurePHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2003H. Yamaji Abstract A self-organized GaN nanotip structure, which was a nanoscale tip-shaped pillar, was fabricated on a GaN surface by reactive ion etching (RIE) using chlorine plasma. The nanotip structure with periods smaller than the wavelength of light can provide antireflection and enhanced transmission effects from the ultraviolet (UV) to the visible region (300 nm , 900 nm). We have found that the height and the density of the nanotip structure can be controlled from 0.1 ,m to 2.0 ,m and from 109 cm,2 to 1011 cm,2 by changing etching conditions, respectively. The nanotip structure with controlled height and density exhibited the drastic improvement of the transmission property in the UV region compared with what is conventionally fabricated. These excellent optical properties of the nanotip structure are expected to improve the performances of light-emitting and photo-detective devices. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Low-loss planar optical waveguides fabricated from polycarbonatePOLYMER ENGINEERING & SCIENCE, Issue 10 2009Jian-guo Chen Low-loss slab waveguides with air as overcladding based on a high glass transition temperature (Tg) polycarbonate were fabricated through spin-coating. Optical absorption and thermo-optic coefficient were investigated by spectrum analysis and prism coupler, respectively. Prism-coupling and charge-coupled device (CCD) camera imaging method were exploited together to evaluate the overall propagation loss of slab waveguides. The measured results of prism coupler were 0.282 dB/cm at 1310 nm and 0.197 dB/cm at 632.8 nm, whereas 0.07 dB/cm at 632.8 nm using CCD camera imaging method. Based on the same material, straight ridge waveguides and multimode interference couplers were fabricated through photolithograph and reactive ion etching, revealing smooth sides and excellent definition. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers. [source] Reactive ion etching of dielectrics and silicon for photovoltaic applicationsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 7 2006Prakash N. K. Deenapanray Abstract This paper investigates the reactive ion etching of SiO2, Si3N4, and Si using CHF3/O2 plasma. In particular, we have characterized the time and rf power dependence of the carrier lifetimes in n- and p-type FZ Si. The time dependence of reactive ion etching (RIE) at different rf powers provide insight into the two competing processes of damage accumulation and damage removal in the near-surface region of the Si during plasma etching. The carrier lifetime, measured using the quasi-steady-state photoconductance (QSSPC) technique, has a quadratic dependence on the rf power, which can be related to changes in the dc self-bias generated by the plasma at different rf powers. The change in carrier lifetime is similar in both n- and p-type Si of the same doping concentration. Using this fact, together with the electronic properties of defects obtained by deep level transient spectroscopy (DLTS), we have modeled the injection-dependence of the measured carrier lifetimes using the Shockley,Read,Hall model. The isochronal annealing behavior of plasma etched Si has also been studied. Copyright © 2006 John Wiley & Sons, Ltd. [source] Fabrication of lab-on chip platforms by hot embossing and photo patterningBIOTECHNOLOGY JOURNAL, Issue 11 2007Devendra K. Maurya Abstract In this paper, we review the approaches developed in our laboratory to fabricate polymer-based microfluidic devices to suit a range of applications in bio- or chemical analysis. Thermoplastic materials such as polycarbonate (PC) and poly(methyl methacrylate) (PMMA) are used to fabricate microfluidic devices via hot embossing. To emboss microchannels, we use hard stamps fabricated in silicon or soft stamps molded on poly(dimethylsiloxane) (PDMS). Hard stamps are fabricated on silicon wafers through photolithography and deep reactive ion etching (DRIE). Soft stamps are fabricated by casting PDMS prepolymer on silicon molds. To enclose the fluidic channels, direct fusion bonding was found to produce the highest bond strength with minimal structural deformation. One-step photolithographic methods have also been explored to produce via photochemical patterning microfluidic structures in photocurable materials. We use the photocurable capabilities of a PDMS copolymer, which incorporates a methacrylate crosslinker. Microfluidic channels are produced via one step-photopatterning processes by crosslinking the prepolymer mixture through a photomask. The smaller feature size attainable was 100 ,m. Structures with higher spatial resolution are fabricated through a photoimprinting process whereby a mold is pressed against the precured mixture during UV crosslinking exposure. The application of the fabricated fluidic devices in electrophoretic ion analysis is also presented. [source] | ||||||||||||||||