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A cerium-doped YAG (Y₃Al 5 O 12 ) phosphor is used as a rare-earth element phosphor for blue light absorption and yellow light emission for a white light source. A solution combustion synthesis, which is a method for producing nano-powder, is a reaction that is spontaneous ignition by reaction heat released through oxidation/reduction reaction between metal nitrate and fuel. Since the reaction speed is fast and it does not go through a separate firing process, it is a method of easily synthesizing nano-powder by simple process. In this study, YAG:Ce nano-powders were prepared by using various fuels in the combustion synthesis method. Depending on the kind of the additive fuel, the reaction of the combustion synthesis process was different, and the shape of the powder particles according to the fuels was also different. The agglomerated particles of nanoparticles were observed and the characteristics of YAG:Ce powders synthesized under various conditions were analyzed.

A Cu metal-ceramic filter composite with high thermal conductivity and a suitable thermal expansion coefficient was designed to be applied to high performance heat dissipation materials. The purpose of using the ceramic filler was to decrease the high coefficient of thermal expansion of Cu matrix utilizing the high thermal conductivity of Cu. In this study, a SiC ceramic filler powder was added to the Cu sol including Zn as a liquid phase sintering agent. The final complex was produced by applying a PVB polymer to prepare a homogeneous precursor followed by sintering in a reducing atmosphere. The pressureless sintered composite showed lower thermal conductivity than pure bulk Cu due to the some residual pores. In the case of the Cu-SiC composite in which 10 wt% of SiC filler was added, it showed a thermal conductivity of 100 W/m·°C and a thermal expansion coefficient of 13.3×10 -6 /°C. The thermal conductivity showed some difference from the theoretical calculated value due to the pores in the composite, but the thermal expansion coefficient did not show a significant difference.

Commercial vehicle pistons should have low thermal expansion and should be able to withstand deformation or mechanical stress. Aluminum alloys are suitable for pistons due to their light weight. However, as aluminum alloys have low strength and friction resistance, cast iron is added through the dipping process in order to increase the quality of pistons. However, the dipping process leads to defects such as defective bonding, void formation, and formation of an oxidation film at the junctions of the two materials due to differences in their properties, which adversely affects the impact resistance and mechanical strength of the product. A theoretical study on the metallurgical bond between the aluminum alloy and the cast iron insert in the piston was conducted to investigate the cause of the defects. The microstructure of the intermetallic bonding layer was observed using scanning electron microscopy and electron dispersive spectroscopy. In this study, defects were found in non-bonding and oxide films and several phases were generated corresponding to different parameters. It was found that processing time and temperature were the main causes of these defects.

Nano-sized SiO₂ based powders were fabricated by a polymer solution technique. Nitrate metal sources and Ludox series silica sol were dissolved in D.I. water and then polyvinyl alcohol solution was added as a polymeric carrier. The metal cations were dispersed well in the solution and a homogeneous polymeric network was formed. The organic-inorganic precursor gels were turned to a porous powder with expanded volume through an explosive oxidation reaction during calcination process. The polymer molecular weight, polymer content and heating rate affected the particle agglomeration and size. The reaction between oxygen and unstable metal cations resulted in a vigorous exothermic reaction and simultaneously the reaction created extensive voids, which accompanied soft powders. The porous powders were crystallized at relatively lower temperature, and easily ground to a very fine powder having nano-sized particles. The crystalline development was also dependent on the polymer type, and the weak hydrogen bonding by optimum polymer content promoted homogeneous entrapment between the -(OH) hydroxyl groups and cations, which are solvates by water molecules.

Various nanocrystalline metal alloy powders were synthesized by solution combustion synthesis in a reducing atmosphere in which a spray pyrolysis process was modified. Miscible Cu-Ni alloy powder and immiscible Ag-Ni alloy powder were synthesized, along with Cu-Y₂O₃ metal-ceramic composite powder. X-ray diffraction, SEM and TEM observations showed that the synthesized powders were nanocrystalline and well alloyed. Alloying occurred via the chemical routes of the decomposition of the metal salts, as well as the oxidation, reduction and sintering processes.

In this study, the fabrication of a wettability patterned surface for cellular micropatterning was investigated using step-wise ion beam processing. A perfluorinated poly(ethylene-co-propylene) (FEP) film was first irradiated using accelerated Xe+ ions with 100 keV of energy at the low current density of 1 μ A/cm² over the entire surface. Second, its confined regions were irradiated at the higher current density of 15 μ A/cm² at various ion fluences through the pattern mask to generate patterns with big differences in wettability. From the analytic results, it was clearly verified that the step-wise irradiation induced effective chemical and morphological changes on the FEP surface, resulting in the successful formation of well-defined micropatterns with relatively hydrophilic and superhydrophobic surfaces. Moreover, the results of in-vitro cell culture showed well-resolved formation of 200 μ m cell micropatterns on the wettability patterned FEP surface due to the individual effects of the relatively hydrophilic and superhydrophobic properties on the cell adhesiveness and proliferation.

Nanosized Ni, NiCo-Y₂O₃ powders were successfully synthesized at low temperature via a simple polymer solution route. As an organic carrier, polyvinyl alcohol (PVA) afforded an atom-scale homogeneous precursor gel, which in turn gave fully crystallized nanosized Ni, NiCo-Y₂O₃ powder upon calcination at a low temperature under an Ar-4% H₂ atmosphere. The PVA content, calcination temperature, heating time, and reduction conditions affected the microstructure and crystallization behavior of the as-synthesized powders. The PVA content also influenced the synthesis behavior and microstructure of the final powder. The particle size increased with an increase in the calcination temperature and decrease in the PVA content. At a PVA-metal ion ratio of 4:1, the measured particle size was about 20 nm. The results of TEM mapping on the NiCo-Y (0.6 wt%) powders revealed a well-dispersed Y₂O₃ phase in the NiCo crystalline matrix.

In this study, thin carbon films with good electrical properties were prepared using commercial novolac resins by ion beam irradiation and carbonization. Novolac films were irradiated with ion beams and then carbonized under inert atmosphere. Based on the FTIR and UV results, the novolac resins were found to be crosslinked by ion beam irradiation without any additives. The Raman and XRD results indicate that carbon films with pseudo-graphitic structures were formed by carbonization of the ion beam irradiated novolac films. The sheet resistance of the prepared carbon films decreased to 1.35 × 102 Ω/ with an increasing fluence. The prepared carbon films showed a good electrical conductivity of ∼2.34 × 102 S/cm.

There are various different approaches in synthesizing graphene including chemical vapor deposition (CVD) and solid-phase method, where gas or solid type carbon source, to be converted into graphene, interacts with transition metals such as nickel and copper. When any thin nickel layer coated atop the polyacrylonitrile (PAN) film is pyrolyzed at a sufficiently high temperature, it is impossible to grow a continuous graphene film with a large area owing to dewetting, which has restricted the subsequent utilization in practical applications. Herein, we suggest a method to synthesize a continuous graphene-like nanofilm with a nickel coated thin PAN film through pyrolysis at 750 to 800 °C in a high-vacuum furnace without a reductive gas flow. The graphene-like nanofilm obtained was characterized using Raman spectroscopy, Raman mapping, field-emission scanning electron microscopy, X-ray photoelectron spectroscopy, and field-emission transmission electron microscopy.

Synroc (Synthetic Rock) consists of four main titanate phases: peroveskite (CaTiO3), zirconolite (CaZrTi2O7), hollandite (BaAl2Ti6O16) and rutile (TiO2). Nano-polycrystalline synroc powders were made by a synthesis combustion process. The combustion process, an externally initiated reaction is self-sustained owing to the exothermic reaction. A significant volume of gas is evolved during the combustion reaction and leads to loosely agglomerated powders. This exothermic reaction provides necessary heat to further carry the reaction in forward direction to produce nanocrystalline powders as the final product. Glycine is used as a fuel, being oxidized by nitrate ions. It is inexpensive, has high energy efficiency, fast heating rates, short reaction times and high compositional homogeneity. In this study, combustion synthesis of nano-sized synroc-B powder is introduced. The fabrication of synroc-B powder result of observation XRD were prepared for polycrystalline (perovskite, zirconolite, hollandite, rutile) structures. The characterization of the synthesized powders is conducted by using XRD, SEM/EDS and TEM.

A solution combustion process for the synthesis of perovskite (CaTiO3) powders is described. Perovskite is one of the crystalline host matrics for the disposal of high-level radioactive wastes (HLW) because it immobilizes Sr and Lns elements by forming solid solutions. Solution combustion synthesis, which is a self-sustaining oxi-reduction reaction between nitrate and organic fuel, the exothermic reaction, and the heat evolved convert the precursors into their corresponding oxide products above 1100 degrees C in air. To investigate the effects of amino acid on the combustion reaction, various types of fuels were used; a glycine, amine and carboxylic ligand mixture. Sr, La and Gd-nitrate with equivalent amounts of up to 20% of CaTiO3 were mixed with Ca and Ti nitrate and amino acid. X-ray diffraction analysis, SEM and TEM were conducted to confirm the formed phases and morphologies. While powders with an uncontrolled shape are obtained through a general oxide-route process, Ca(Sr, Lns)TiO3 powders with micro-sized soft agglomerates consisting of nano-sized primary particles can be prepared using this method.

In this paper, the simple and biocompatible micropatterning of cell-repellent poly(N-isopropylacrylamide) (PNIPAAm) on a cell-adhesive substrate by ion beam micropatterning to control cell adhesion is described. Cell-repellent PNIPAAm films spin-coated on cell-adhesive tissue culture polystyrene (TCPS) substrates were selectively irradiated by energetic proton ions at various fluences through a pattern mask, and subsequently developed to create the micropatterns of PNIPAAm. Well-defined negative-type PNIPAAm micropatterns were successfully created on the TCPS substrates at fluences higher than 5 x 10¹⁴ ions/cm², and their chemical properties were dependent on the fluence. Moreover, based on the results of the protein adsorption and in-vitro cell culture tests, 200 µm well-defined micropatterns of mammalian cells were clearly formed on the PNIPAAm-micropatterned TCPS substrates though the preferential adsorption and growth of cells on the TCPS regions due to the strong cell-repellency of PNIPAAm.

Cu nano particles were fabricated at a very low temperature via polymer solution and reduction firing processes using a polyvinyl alcohol (PVA) and Ar-4%H2 gas mixture. In the process, copper nitrate and 5 wt% PVA solution were dissolved in D.I. water and the organic-inorganic precursor sols were dried to porous gels. The precursor gels were calcined in an air atmosphere, and then refired at 250 degrees C-300 degrees C under an Ar-4%H2 atmosphere for the reduction of CuO. The morphology of precursor gels and CuO and Cu powders was strongly dependent on the PVA content, and the as- calcined CuO readily deoxidized to Cu with minimal residual carbon. The polymer also contributed to an atomic-scale copper cation distribution, which resulted in nano-sized CuO and Cu powders. The Cu powder synthesized with PVA content in a 4:1 ratio showed a crystallite size of about 20 nm or less. In this paper, the microstructure changes of Cu nano particles at each set of processing conditions were examined by SEM and TEM observations.

Copper (Cu) nano particles were successfully fabricated at a significantly low temperature through a simple polymer solution route. In the process, the organic-inorganic precursor sols were turned to porous gels exhibiting volume expansion during the drying process. The PVA polymer, as an organic carrier, contributed to make an atom-scale homogeneous copper precursor gel, which resulted in fully crystallized, nano-sized copper powders through a low calcination temperature of 300 °C under Ar-4%H2 atmosphere. Variations in the processing technique, such as the content of PVA and calcination temperature, affected the microstructure and crystallization behavior of the synthesized powders. The copper powder synthesized with the PVA content of 4:1 ratio showed a crystallite size of about 10 nm or less with a high surface area. In this paper, the PVA solution technique for the fabrication of a nano-sized copper powder is introduced. The effects of the PVA content and calcination conditions on the powder morphology and crystallization are also studied. The characterization of the synthesized powders is conducted by using XRD, DTA/TG, SEM and TEM.

A simple and facile method for the patterning of gold nanoparticles (GNPs) was described via selective ion irradiation and oxygen plasma etching. Thin Pluronic films containing HAuCI4 as the precursor of GNPs were selectively irradiated through a pattern mask with 200 keV proton ions to generate GNP-embedded Pluronic patterns. The Pluronic was then removed by an oxygen plasma etching process for the pattern formation of GNPs. Based on the results of the UV-Vis, FE-SEM, and EDX analyses, 50 μm negative-tone line patterns of the GNP-embedded Pluronic were successfully generated at a fluence of less than 1 x 10(16) ions/cm2. The changes in the morphology and elemental composition of the formed GNP-embedded Pluronic patterns with different time periods of oxygen plasma etching were investigated using an FE-SEM with an EDX. The experimental results demonstrated that the patterns of GNPs were effectively generated by the oxygen plasma etching of the formed GNP-embedded Pluronic patterns for 15 min. Furthermore, the XRD results revealed that GNPs in the patterns formed by ion irradiation were further grown during the subsequent oxygen plasma etching.

Basic manipulations of discrete liquid drops on opened microfluidic chips based on electrowetting on dielectrics were described. While most developed microfluidic chips are closed systems equipped with a top plate to cover mechanically and to contact electrically to drop samples, our chips are opened systems with a single plate without any electric contact to drops directly. The chips consist of a linear array of patterned electrodes at 1.8 mm pitch was fabricated on a glass plate coated with thin hydrophobic and dielectric layers by using various methods including photolithography, spin coating and ion sputtering. Several actuations such as lateral oscillation, colliding mergence and translational motion for 3-10 μL water drops have been demonstrated satisfactory. All these kinetic performances of opened chips were similar to those of closed chip systems, indicating superiority of a none-contact method for the transport of drops on opened microfluidic chips actuated by using electrowetting technique.

12CaO x 7Al2O3, insulator (C12A7) doped indium tin oxide (ITO) (ITO:C12A7) films were fabricated using a radio frequency magnetron co-sputtering system with ITO and C12A7 targets. The qualitative and quantitative properties of ITO:C12A7 films, as a function of C12A7 concentration, were examined via X-ray photoemission spectroscopy and synchrotron X-ray scattering as well as by conducting atomic force microscopy. The work function of ITO:C12A7 (1.3%) films of approximately 2.8 eV obtained by high resolution photoemission spectroscopy measurements make them a reasonable cathode for top-emission organic light-emitting diodes.

The electrowetting of water drops on a dielectric fluoropolymer film was studied experimentally. The dependence of the contact angles of the water drops on the applied voltage has been well explained in the low-voltage limit by using the classical Young-Lippmann theory. With this theory, the thicknesses of films coated on glass substrates by using a spin-coater were obtained indirectly by fitting the contact angle data and were confirmed by using X-ray reflectometry. The two sets of results showed a good agreement. In addition, we confirmed that the contact angle saturation at high voltage were consistent with Peykov's model.

In this study, a simple surface patterning method to create micropatterns of mammalian cells on indium tin oxide (ITO) substrates was developed using ion implantation. Thin polystyrene (PS) films spin-coated on an ITO glass was selectively implanted with accelerated proton ions through a pattern mask and then developed to generate PS micropatterns. Well-organized negative PS patterns were generated on the ITO glass. The results of the in vitro cell culture on the PS-patterned ITO glass with two types of cancer cell lines revealed the formation of well-defined cell patterns through a selective cell adhesion and proliferation only onto the ITO regions separated by PS regions. This facile method for cell patterning may be used to create a desired platform for cellular device applications, such as biosensors and cell microarrays.

In this study, a facile route to fabricate micropatterns of cells is presented on the basis of electron irradiation of poly(dimethylsiloxane) (PDMS). PDMS films were irradiated with electron beams through a pattern mask with micrometer-sized grids. After irradiation, the changes in the chemical composition, morphology, and wettability of the PDMS surface were investigated by using an X-ray photoelectron spectrometer, an atomic force microscope, and a contact anglometer. The results of the surface analysis revealed that the hydrophobic PDMS surface was changed into a hydrophilic one by the electron irradiation. Furthermore, on the basis of cell culturing on the selectively-irradiated PDMS, cells such as NIH3T3 and L929 were selectively adhered to and proliferated on the irradiated regions of the PDMS surface, resulting in the micropatterns of the cells on the PDMS surface.

Nano-sized nickel oxide powders were synthesized by an organic-inorganic solution route employing polyvinyl alcohol (PVA) as an organic carrier. In this study, it was possible to control the physical properties of the nickel oxide powders by change of the PVA content. The experimental factors, such as the PVA content, heating temperature and time, were studied for the synthesis of nano crystalline powders. Nickel nitrate, (Ni(NO3)2, reagent grade) was used as a source of nickel cation. Once the cation source was completely dissolved in de-ionized (DI) water, 5 wt% PVA solution was added to the sol solution. The resulting gel-type precursors were completely dried and then calcined or crystallized at various temperatures in an air atmosphere in a box furnace. In the high PVA content of 2:1 mixing ratio, nano crystallite nickel oxide powders of below 5 nm in size with a high specific surface area of 151.19 m2/g were obtained at low temperature of 400 degrees C for 1 h. The PVA polymer contributed to homogeneous nickel cations in atomic scale through the fabrication process of the sol precursor. In this paper, the PVA solution technique for the fabrication of nano-sized nickel oxide powders is introduced. The effects of PVA content and heating time on the powder crystallization, morphology and specific surface area are also studied. The characterization of the synthesized powders is examined by using XRD, DTA/TG, TEM and nitrogen gas adsorption.

Micropatterning of titanium dioxide (TiO2) on the surface of thin poly(dimethyl siloxane) (PDMS) films was described by means of proton irradiation and liquid-phase deposition (LPD) techniques. The surface of thin PDMS films was irradiated with accelerated proton ions through a pattern mask in the absence or presence of oxygen in order to create hydrophilically/hydrophobically patterned surfaces. The results of the surface analysis revealed that the PDMS films irradiated at the fluence of 1 x 10(15) ions cm-2 in the presence of oxygen showed the highest hydrophilicity. The LPD of TiO2 particles on the patterned PDMS film surface showed a selective deposition of TiO2 on the irradiated regions, leading to well defined TiO2 micropatterns. The crystal structure of the formed TiO2 films was found to be in an anatase phase by X-ray diffraction analysis. This process can be applied for patterning various metal and metal oxide particles on a polymer substrate.

Nano-sized yttria (Y2O3) powders were successfully synthesized at a low temperature of 400 degrees C by a simple polymer solution route. PVA polymer, as an organic carrier, contributed to an atom-scale homogeneous precursor gel and it resulted in fully crystallized, nano-sized yttria powder with high specific surface area through the low temperature calcination. In this process, the content of PVA, calcination temperature and heating time affected the microstructure and crystallization behavior of the powders. The development of crystalline phase and the final particle size were strongly dependant on the oxidation reaction from the polymer burn-out step and the PVA content. In this paper, the PVA solution technique for the fabrication of nano-sized yttria powders is introduced. The effects of PVA content and holding time on the powder morphology and powder specific surface area are also studied. The characterization of the synthesized powders is examined by using XRD, DTA/TG, SEM, TEM and nitrogen gas adsorption. The yttria powder synthesized from the PVA content of 3:1 ratio and calcined at 400 degrees C had a crystallite size of about 20 nm or less with a high surface areas of 93.95-120.76 m2 g(-1).

Poly(vinyl pyrrolidone) (PVP)-stabilized silver nanoparticles (NPs) were used as a new nanocomposite resist for electron beam lithography. A nanocomposite resist prepared by reducing silver nitrate in an alcoholic PVP solution was patterned by using a scanning electron microscope equipped with a nanometer pattern generation system. Well-defined negative tone patterns with a good sensitivity of 200 microC/cm2 and a contrast of 2.83 were obtained using the prepared nanocomposite resist. In addition, the changes in the morphology and structure of the resist patterns with a thermal treatment temperature were investigated by a FE-SEM with an EDX. The results revealed that the patterns of Ag NPs were formed through sintering the formed resist patterns at above 300 degrees C.

Various properties of electrowetting such as reversibility, reproducibility and mobility have been investigated experimentally. A conductive water drop on a thin hydrophobic film of amorphous fluropolymers coated on the counter electrode showed unexpectedly the poor reversibility under the discontinuous voltage, so called the contact angle hysteresis. The hysteresis could not been completely suppressed by inserting additionally a thick parylene-C film which has the high dielectric constant and no pinholes. However, both the reversibility and the reproducibility have been enhanced under the continuous voltage starting from the highest absolute electric potential.

Patterned graft polymerization of a functional monomer on a hydrophobic polymer surface was proposed for biomolecule patterning. A poly(vinylidene fluoride) (PVDF) film surface was selectively activated by ion implantation through a pattern mask and acrylic acid (AA) was then graft polymerized onto the activated regions of the PVDF surfaces. The peroxide concentration on the implanted surface depended on the fluence, which had a considerable effect on the grafting degree of AA. Afterwards, amine-functionalized biotin and probe DNA were immobilized on the poly(acrylic acid)-grafted regions of the PVDF surfaces. Specific binding of biotin with streptavidin and hybridization of probe DNA with complimentary DNA proved successful protein and DNA patterning and well-defined 50 microm dot-type patterns of the streptavidin and DNA were obtained. These results confirmed the potential of this strategy for patterning of various biomolecules.

An alternating conjugated copolymer composed of pyrene and bithiophene units, poly(DHBT-alt-PYR) has been synthesized. The synthesized polymer was found to exhibit good solution processibility and thermal stability, losing less than 5% of their weight on heating to approximately 370 degrees C. The synthesized polymer showed its maximum absorption and peak PL emission at 401 and 548 nm, respectively. The optical band gap energy of the polymer was determined by absorption onset to be 2.64 eV. Highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of the polymer was determined to be -5.48 and -2.84 eV by cyclic voltametry (CV) and the optical band gap. The polymer photovoltaic devices were fabricated with a typical sandwich structure of ITO/PEDOT:PSS/active layer/LiF/Al using poly(DHBT-alt-PYR) as an electron donor and C60-PCBM or C70-PCBM as electron acceptors. The open circuit voltage, short circuit current and fill factor of the device using C70-PCBM as an acceptor were 0.75 V, 3.80 mA/cm2 and 0.28, respectively, and the maximum power conversion efficiency of the device was 0.80%.

A convenient and effective method to pattern polymer-embedded metal nanoparticles by ion irradiation has been developed. The thin Pluronic films containing silver nitrate as a precursor of silver nanoparticles were irradiated through a pattern mask with accelerated proton (H+) ions. It was found from the UV-Vis measurement that the formation of silver nanoparticles in the Pluronic matrix was dependant on the amount of silver nitrate. The 50 microm line (pitch 150 microm) patterns of the Pluronic containing silver nanoparticles were obtained with the thin film irradiated to 1 x 10(16) ions/cm2. The heat treatment effect on the morphology of the patterns was investigated by using a scanning electron microscope with an energy dispersive X-ray spectrometer. The results confirmed that the silver nanoparticles were successfully embedded in the Pluronic patterns and the patterns were changed into large silver particles by a heat treatment above 350 degrees C.

This study describes a new patterning method of poly(vinyl pyrrolidone) (PVP) containing silver nanoparticles by using ion irradiation. The thin films prepared from PVP/silver nanoparticle solutions were irradiated through a mask with accelerated H+ ions. Well-defined 50 microm line (pitch 150 microm) patterns were generated from the film irradiated at 1 x 10(16) ions/cm2. The heat treatment effect on the morphology of the patterns was investigated by using a scanning electron microscope with an energy dispersive X-ray spectrometer. The results confirmed that the silver nanoparticles were successfully immobilized in the PVP patterns and the patterns were changed into silver particles by heat treatment above 300 degrees C.

Multi-walled carbon nanotubes (MWCNTs) were functionalized by radiation-induced graft polymerization of acrylic acid onto the surface of MWCNTs in order to improve their dispersibility in water. 1H NMR, Raman spectroscopy, TEM, and TGA techniques were used to characterize the resulting functionalized MWCNTs. The grafting degree was dependent on the grafting conditions such as the absorbed dose and the monomer concentration. The experimental results confirmed that poly(acrylic acid) chains were successfully grafted onto the surface of the MWCNTs. The poly(acrylic acid)-grafted MWCNTs showed a much better water dispersibility than the pristine MWCNTs.

We synthesized a new photo-patternable organic/inorganic hybrid material, polyhedral oligomeric silsesquioxane (POSS) derivative containing cyclohexene-1,2-epoxide functional groups (POSS-EPOXY), and fabricated an organic thin film transistor (OTFT) using pentacene as an active p-type organic semiconductor and POSS-EPOXY as a gate dielectric layer to demonstrate its applicability for organic electronics. The pentacene transistor with the POSS-EPOXY layer shows comparable transistor characteristics as that with the prototypical polymeric gate insulator of poly(vinylphenol) (PVP). They exhibit field-effect mobility of micro(FET) approximately 0.075 cm2/Vs, threshold voltage of V(T) = -22.2 V, the on/off current ratio of 7 x 10(5), and the subthreshold slope of 3.9 V/dec.