Highly fluid repellent have application in many industries ranging from marine to biomedical due to their self-cleaning antifouling properties. The development and implementation of these superhydrophobic (water contact angle >150 degrees ) and superoleophobic (oil contact angle > 150 degrees ) surfaces were studied in this thesis. We focused our studies on paper as a substrate for these superhydrophobic and superoleophobic surfaces. Cellulose based paper is a biodegradable, inexpensive material that is ideal for disposable use applications. Applying an oxygen plasma etching technique combined with the deposition of a fluoropolymer from a pentafluoroethane precursor, superhydrophobic paper can be attained. This superhydrophobic paper is functionalized by printing wax islands onto the surface, thereby creating areas of high fluid adhesion. These wax functionalized sheets are used to sample droplets from bulk droplets, with the sampled volume being controlled by the hysteresis of the wax island. Disposable biomedical devices can be envisioned from these wax designs. While these superhydrophobic surface excel at repelling water, they continue to readily absorb water. Formation of paper that is both superhydrophobic and superoleophobic, or superamphiphobic, is accomplished through a combination of steps: mechanical fiber refining, solvent exchange processing and plasma treatment. The fiber refining creates nano-scale fibrils that are separated in the solvent processing. Subsequent plasma treatment of oxygen etching and fluoropolymer deposition creates superamphiphobic paper, exhibiting contact angles of > 150 degrees for water, ethylene glycol, motor oil and n-hexadecane. Further studies were conducted to increase the strength of these superamphiphobic sheets by using layered paper. Development of superhydrophobic paper from a hydrophilic diamond-like carbon surface coating was also demonstrated. When combined with oxygen plasma etching, diamond-like carbon coated paper sheets attain superhydrophobic properties similar to fluoropolymer coated sheets. Based on the knowledge gained from the studies on paper, superhydrophobic surfaces are created on 304 and 316 stainless steels. Samples are etched in hydrofluoric acid and then passivated in nitric acid to create the necessary surface structure. Deposition of fluoropolymer onto the etched samples yields superhydrophobic properties.

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 169-171). Available also in a digital version from Dissertation Abstracts.

Thesis (M.S.)--Rochester Institute of Technology, 1994. / Typescript. Includes bibliographical references (leaves 98-99).

This thesis reports the characterization and development of nanolithography using Electron Beam Lithography system and nanoscale plasma etching. The standard Bosch process and a modified three-pulse Bosch process were developed in STS ICP and Plasma ICP system separately. The limit of the Bosch process at the nanoscale regime was investigated and documented. Furthermore, the effect of different control parameters on the process were studied and summarized in this report. 28nm-wide trench with aspect-ratio of 25 (smallest trench), and 50nm-wide trench with aspect ratio of 37 (highest aspect-ratio) have been demonstrated using the modified three-pulse process. Capacitive resonators, SiBAR and IBAR devices have been fabricated using the process developed in this work. IBARs (15MHz) with ultra-high Q (210,000) have been reported.

No description available.

A gas phase kinetic model for the CF���/O��� microwave discharge plasma and afterglow of our laboratory has been developed. A reaction pathway identifying the major chemical reactions is proposed. The rate coefficients of the electron impact dissociation reactions are determined at three different plasma powers using both published electron molecule collision cross section data and plug flow analysis of data collected in our system. Agreement between calculated and experimental rate coefficients is better than 20%. Fluid simulations of a two-dimensional mathematical model were performed using computational fluid dynamics. It is found that the model reproduced qualitatively the general trends of the experimental data. The effects of plasma power, feed gas composition, residence time and pressure on the product distribution of the system are studied. CF��� conversion increases with power and residence time. The variation of CF��� conversion and carbon containing species distribution falls into two regimes. In the oxygen rich regime (below 25 mole % CF��� in the feed), CO��� is found to be the major product of CF��� decomposition; homogeneous recombination reactions between atomic oxygen and the free radicals are found to be the dominant mechanism in the afterglow region resulting in high CF��� conversions. Homogeneous reactions convert CO to CO���. In the CF��� rich regime (above 50 mole % CF���), COF��� is found to be the major product of CF��� decomposition. Recombination reactions of CF��� with atomic fluorine dominate in the afterglow region and limit conversion. Lowering pressures result in increased conversion of CF��� and increased concentration of the carbon containing species. / Graduation date: 1998

This study demonstrates a high-performance capillary electrophoresis electrochemical (CE-EC) microchip featuring embedded the palladium nanoelectrode ensemble (Pd-NEE) as the decoupler. The Pd-NEE is fabricated utilizing a new composition of electroless plating bath for depositing palladium in the porous polycarbonate thin film. Palladium has the adsorbability and permeability to hydrogen, such that the produced Pd-NEE is able to eliminate the hydrogen formation from the high separation voltage and to reduce the background current for electrochemical detection. Moreover, this study adopts the oxygen plasma to etch the nanoelectrode ensemble to enlarge the exposed surface areas to further enhance the decoupling performance of the Pd-NRE. Experimental results show that the developed Pd-NEE decoupler is capable of decoupling the electrophoretic current such that the hydrogen formation on the electrochemical electrodes was suppressed. Results indicate the developed Pd-NEE decoupler greatly enhance the S/N ratio for the electrochemical signal and lower the detectable concentration for the bio-sample of the dopamine and catechol. The detection limit of dopamine and catechol are 50 nM and 100 nM using the microchip with the Pd-NEE decoupler. Furthermore, results also indicate that the palladium nanorod ensemble (Pd-NRE) decoupler produced using the oxygen plasma etching of Pd-NEE have better electrochemical detection performance in compared with the Pd-NEE decoupler. The background current of the electrochemical detection obtained with the microchip with Pd-NRE decoupler is about 5.6 pA at applied electric field of 800 V/cm electric field. In addition, combining the gold nanorod ensemble (GNRE) as the working electrode, the detection limit is lower to 10 nM and 50 nM, respectively. This study presents a high efficiency CE-EC microchip with a Pd-NRE decoupler and a GNRE working electrode which not only decreases the background current but improves the detection limit.

The current semiconductor device manufacturing requires more strict control of plasma etching. In this research, plasma etching was investigated through gas phase characterization and interface reactions. Hydrogen and nitrogen were added to Ar plasmas to manipulate the electro-physical properties that were measured by a Langmuir probe system. Hydrogen addition modified the EEDF (electron energy distribution function) by increasing the electrons in high energy range. Adding N2 formed a strong bi-Maxwellian distribution. Gas addition caused the transition between ohmic and stochastic heating. Ar-CH4-H2 and Ar-N2-H2 plasmas were also tested. Hydrogen atom beam was used on porous silicon dioxide based low-k films to remove silanol groups that were generated due to the damage of films during pattern transfer. At H2 atom beam process at 150 C moved close to 60% silanol groups were removed in less than 3 min with an etching rate of 15 A/min. The apparent activation energy was 2.4 kcal/mol. Hydrogen atoms reacted with Si-O-Si and methyl groups. The etching mechanisms of CH4/H2/Ar plasma for InP were analyzed by a beam reactor system. Sputtering yield was measured, threshold energy was approximately 60 eV. Inert ion beam assisted chemical reactions gave higher etching rate. The CH4 concentration had no strong effect on etching rate after 5%. Etching rate was not sensitive to temperature up to 150 C. The adsorption of methyl groups to the surface was proposed as rate limiting step. Chemical reaction effectively reduced the surface roughness.

No description available.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xi, 99 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 80-83).