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In light of recent developments in genomic technology and the rapid accumulation of genomic information, a major transition toward precision medicine is anticipated. However, the clinical applications of genomic information remain limited. This lag can be attributed to several complex factors, including the knowledge gap between medical experts and bioinformaticians, the distance between bioinformatics workflows and clinical practice, and the unique characteristics of genomic data, which can make interpretation difficult. Here we present a novel genomic data model that allows for more interactive support in clinical decision-making. Informational modelling was used as a basis to design a communication scheme between sophisticated bioinformatics predictions and the representative data relevant to a clinical decision. This study was conducted by a multidisciplinary working group who carried out clinico-genomic workflow analysis and attribute extraction, through Failure Mode and Effects Analysis (FMEA). Based on those results, a clinical genome data model (cGDM) was developed with 8 entities and 46 attributes. The cGDM integrates reliability-related factors that enable clinicians to access the reliability problem of each individual genetic test result as clinical evidence. The proposed cGDM provides a data-layer infrastructure supporting the intellectual interplay between medical experts and informed decision-making.

This study analyzed the outcomes of myelodysplastic syndrome patients treated with azacitidine. Between August 2006 and June 2008, a total of 126 patients were treated with azacitidine at a dose of 75 mg/m(2)/day subcutaneously for 7 days, which was repeated every 28 days. The median age of the patients was 64 (range, 20-82) years. Forty-three patients (33.4%) were classified as intermediate-2 and high risk according to International Prognostic Scoring System (IPSS), while 61 patients (47.3%) were classified as high and very high risk according to WHO Prognostic Scoring System (WPSS). Sixty patients (47.6%) exhibited a response at the median of 3 (range, 1-5) cycles. A complete response was observed in 21 patients (16.7%), a partial response in six patients (4.8%), and total hematologic improvement in 61 patients (48.4%). For the IPSS risk group, the median survival for the patients with intermediate-1 was 20.0 months, for intermediate-2 was 14.9 months, and for high risk was 6.3 months (p = 0.008). For the WPSS risk group, the median survival duration was 21.3 months for the very low and low risk patients, 16.5 months for intermediate risk patients, and 14.9 months for the high and very high risk patients (p = 0.003). The patients with higher than normal lactate dehydrogenase (LDH) levels at the time of diagnosis showed a poor survival (p = 0.003). The median survival duration for the patients with high LDH levels was 13.9 months, while that for the patients with normal LDH levels was 20.6 months. The multivariate analyses revealed that high LDH levels [hazard ratio (HR) 4.384, p < 0.001] and high and very high WPSS risk group (HR 3.855, p = 0.014) were significantly associated with a worse survival, whereas a response to azacitidine was identified as a good prognostic factor for survival (HR 0.224, p = 0.019). In conclusion, while the pretreatment risk group and initial LDH levels were both confirmed as important prognostic factors to predict the outcomes for patients treated with azacitidine, more effective therapies are still needed to prevent disease progression.

MgO thin films are widely used in plasma display panels (PDPs) to protect the dielectric layer, which is composed of PbO2, B2O3, and SiO2 compound, against ion bombardment during discharge. To improve the electrical properties of the MgO thin films, (Ba,Sr,Ca)CO3 or LaB6, which has a lower work function than that of MgO, added to the MgO films. The effects of (Ba,Sr,Ca)CO3 or LaB6 addition on the electrical properties, microstructure, and electronic band structure were investigated. In the case where (Ba,Sr,Ca)CO3 was added, the firing voltage, which is the voltage when the panel is ignited the first time during increasing input voltage, was about 18.4 V lower than that of the conventional MgO films. In the case where LaB6 was added, the firing voltage was also reduced by about 24 V. The luminance and luminous efficiency were also increased. Of particular interest was the valence band spectra changed after adding (Ba,Sr,Ca)CO3 or LaB6. The valence band edge, which is the top of the valence band, was shifted to lower binding states and the width of the valence band was increased. Moreover, the band gap was slightly reduced. Considering the emission mechanism of MgO films in plasma display panels, these results mean that the secondary electrons can be ejected more easily and the ejected electrons have more energy. Therefore, the addition of (Ba,Sr,Ca)CO3 or LaB6 might improve the electrical properties.

The importance of the secondary electron emission of the protective layer in the alternating current plasma display panels is widely known. However, the difficulty in measuring the secondary electron emission coefficients (γ) of insulating materials has hampered efforts to obtain accurate estimates of their values. To overcome the difficulty of direct measurement, we devised a calculating γ using the spectra of x-ray photoelectron spectroscopy (XPS) and a well-defined theory. The XPS spectra of the valence and core bands of MgO, Al2O3, and Y2O3 films, which were deposited by e-beam evaporation, were measured. Calculations of the γ values were conducted for the case when gas ions such as He, Ne, Ar, and Xe slowly approach the solid surface.

In order to examine the electrical and physical properties of Al2O3 layers with dual thickness on a chip, Pt gate/Al2O3 with dual thickness/p-type Si (100) samples were fabricated using atomic-layer deposition, separation photolithography, and 100:1 HF wet etching to remove the first Al2O3 layer. Dual metal-oxide-semiconductor (MOS) capacitors with thin (physical thickness, ∼4.5 nm, equivalent oxide thicknesses (EOT): 2.8 nm) and thick (physical thickness, ∼8.2 nm, EOT: 4.3 nm) Al2O3 layers showed a good leakage current density of −5.4×10−6 A/cm2 and −2.5×10−9 A/cm2 at −1 V, respectively; good reliability characteristics as a result of the good surface roughness; low capacitance versus voltage measurements (C-V) hysteresis; and a good interface state density (∼7×1010 cm−2eV−1 near the midgap) as a result of pre-rapid thermal annealing (pre-RTA) after depositing the Al2O3 layer compared with the single MOS capacitors without the pre-RTA. These results suggest that dual Al2O3 layers using the dual gate oxide (DGOX) process can be used for the simultaneous integration of the low power transistors with a thin Al2O3 layer and high reliability regions with a thick Al2O3 layer.

The electrical conduction mechanisms of approximately 8-nm-thick Ta2O5 films grown by metalorganic chemical vapor deposition were investigated by measuring the current density–voltage characteristics at various temperatures. The Ta2O5 films were grown in two steps with or without intermittent annealing at 450 °C under an O3 atmosphere with ultraviolet light radiation (UV-O3 treatment). High-resolution transmission electron microscopy of the films after post-deposition annealing at 750 °C under an O2 atmosphere showed that the intermittent UV-O3 treatment improved the crystallization of the film during post-annealing. Auger electron spectroscopy of the variously treated samples showed that the improvement in crystallization was due to the increase in the oxygen concentration of the Ta2O5 films by the UV-O3 treatment. The Ta2O5 film without the UV-O3 treatment mostly exhibited a Poole–Frenkel conduction behavior with the electron trap level of 0.62 eV from the conduction band edge. The whole layer UV-O3 treated Ta2O5 films also showed a Poole–Frenkel conduction behavior with an almost identical electron trap level and a reduced density. The partially UV-O3 treated Ta2O5 films exhibited a direct tunneling behavior in a relatively low voltage region by the tunneling through the thin (∼3.8 nm) UV-O3 treated surface layer. However, these films showed a Poole–Frenkel conduction behavior in the high-voltage region. In general, the UV-O3 treatment was an efficient method to reduce the leakage current of the high-dielectric Ta2O5 films.

We have fabricated planar 4H-SiC, metal-semiconductor field-effect transistors (MESFETs) with high-quality metal/SiC contacts. To eliminate potential damage to the gate region caused by etching and simplify the device fabrication process, gate Schottky contacts were formed without any recess gate etching, and an ideality factor of 1.03 was obtained for these gate contacts. The interface state density between the contact metal and SiC was 5.7×1012 cm−2eV−1, which was found from the relationship between the barrier height and the metal work function. These results indicate that the interface was well controlled. Thus, a transconductance of 30 mS/mm was achieved with a 3-µm gate length as the performance figure of these MESFETs with high-quality metal/SiC contacts. Also, a low ohmic contact resistance of 1.2×10−6 Θcm2 was obtained for the source and drain ohmic contacts by using ion implantation.

Pt thin films of various thicknesses (30 nm ∼ 200 nm) were deposited on Si wafers with SiO2, Ti, TiO2, or IrO2 buffer layers at various temperatures (room temperature ∼200 °C) by a direct current magnetron sputtering process. The Pt films showed a strong (111)-preferred texture irrespective of the thickness, under-layer, and growth temperature. The authors previously reported [J-E. Lim, D-Y. Park, J.K. Jeong, G. Darlinski, H.J. Kim, and C.S. Hwang, Appl. Phys. Lett. 81, 3224 (2002)] that the films were composed of three kinds of grains with slightly different (111) lattice parameters (bulklike, 1.0% and 2.1% larger). This study details the microstructural variations of the Pt films according to the variations of experimental parameters. The different deposition conditions produced slightly different crystalline structures, but the three different (111) lattice parameters were always found. Epitaxial (200) Pt films on a (200) MgO substrate and a highly (111) textured Au thin film on a SiO2/Si did not show the same splitting in the lattice parameter. The grains with 1.0% and 2.1% larger (111) lattice parameter almost disappeared after postannealing at 1000 °C. However, surface chemical binding of the Pt film before and after annealing was unchanged. Therefore, it is believed that the lattice parameter splitting in the (111) textured Pt film originated from the interfacial grains with the distorted crystal structure due probably to growth stress.

MgO single crystals and thin films were intentionally hydrated to determine the critical factors affecting the hydration behavior. The degree of hydration was affected by the crystallographic orientation in the initial stages. The (111) plane showed a higher tendency to hydrate than (100). The shape of the hydration clusters also differed according to the orientation of MgO single crystals. After long-term hydration, the density and grain size appeared to influence the hydration along with the orientation. On low-density thin films, Mg atoms are easily supplied to the surface, which induces large hydration clusters. As the grain boundary area increased, the number of nucleation sites for the formation of hydration clusters increased, which increases the number of clusters. Hydration also occurred in the inner part of thin films. The density of thin films is the most important property in this case because it governs the diffusion of Mg atoms, water, and OH through the thin films.

Pb(Zr, Ti)O3(PZT) thin films were deposited on Pt/SiO2/Si substrates by metalorganic chemical vapor deposition using solid delivery system. The effects of deposition parameters such as the substrate temperature, the concentration of Pb precursor in the precursor mixtures, and the reactor pressure on the structural and electrical properties of PZT thin films were investigated. To obtain single-phase PZT thin films, the optimal range of the substrate temperature should be between 600 and 650 °C. The PbO content in PZT thin films was proportional to the fraction of Pb in the precursor mixture below 550 °C, but it was independent of the fraction of Pb in the mixture above 600 °C. With the increment of the reactor pressure, Zr contents in PZT thin films were increased, and the Pb/(Zr + Ti) ratio became more stoichiometric so that the ferroelectric properties were improved.

The microstructural evolution, including preferred orientation and surface morphology, of ZnO films deposited by rf magnetron sputtering was investigated with increasing film thickness. Preferred orientation of the ZnO films changed from (0002) → (1011) → (1120) and fine and dense columnar grains also changed to large elongated grains with increasing thickness. Such selective texture growth was explained with an effect of highly energetic species bombardment on the growing film surface. The relationship between preferred orientation change and microstructural evolution was also discussed.

An experimental study has been performed in an attempt to seek some possibilities of obtaining the solutions of heat transfer problems related to rotor-stator disk cavity systems of gas turbine engines by analogy with corresponding problems in mass transfer which arises from using naphthalene sublimation technique. Measurements are made to examine the effects of rotational Reynolds number, the flow rate and the gap ratio on the radial pressure distributions. Pressure inversion phenomenon has been verified to exist for the case of shrouded disks with radial clearance, which perform better in terms of heat transfer, too, than those with axial clearance. The stator flow reattachment points are determined directly by the dual sensor pressure probes and compared well with those estimated from the distributions of static pressure and mass transfer coefficients.

We deposited (Mn,Zn,Fe)1−xO thin films of a wüstite structure on SiO2/Si(100) by ion beam sputtering using a single-crystal Mn-Zn ferrite target. The wüstite structure of the as-deposited film, confirmed by XRD, TEM, and XPS analysis, appeared to originate from an oxygen-deficit ambient and also from the preferential resputtering of the oxygen ions in films during deposition. The as-deposited films showed ferrimagnetic characteristics having quite a large Ms in spite of their crystallographic structure, wüstite. Such an unusual phenomenon is presumably due to the different magnetic moments of the constituent cations with disordered distribution. This wüstite phase could be transformed into the spinel ferrite phase with the same preferred orientation during postannealing under an appropriate oxygen partial pressure. The interplanar distance of the as-deposited films decreased with increasing Ts due to a release of compressive stress. The Ms of the film had a maximum value at about 275 °C, while the resistivity, mainly governed by the grain boundaries, was almost the same irrespective of Ts.

We have investigated the effects of process parameters such as rf power, substrate, and gas pressure PAr on preferred orientation, microstructure, and magnetic properties of Ni-Zn-Cu ferrite thin films deposited by conventional rf magnetron sputtering. The texture structure was developed in the ferrite films deposited on the SiO2/Si(100) substrate at low rf power conditions. The ferrite film on the Si(111) substrate always had (111) texture irrespective of process parameters due to lattice matching, but the texture of the ferrite film on SiO2/Si(100) changed from (111) to (100) and finally returned to (111) orientation again with decreasing PAr. Such behavior would occur presumably due to the characteristic atomic stacking sequence corresponding to a given condition of the ion bombardment. The ferrite films deposited at low PAr had a denser microstructure consisting of tightly packed columnar grains with a smoother surface, better adhesion to the substrate, and better crystallinity than those at high PAr. Hc‖ of ferrite film deposited at low PAr was larger than that at high PAr and also larger than Hc⊥ of that deposited at the same PAr because larger compressive stress was induced at low PAr than at high PAr.

Ferroelectric PbTiO3 thin films were deposited on bare silicon and Pt/SiO2/Si substrates by metalorganic chemical vapor deposition in a temperature range from 270 to 550°C. The deposition of a single phase PbTiO3 thin film did not occur on bare silicon substrates. Instead a double layer of lead-silicate and PbTiO3 was formed owing to a serious diffusion of lead and oxygen ions into silicon substrates. But on Pt/SiO2/Si substrates, a single phase PbTiO3 oriented parallel to a-and c-axis was grown at a substrate temperature as low as 350°C even without a high temperature post-annealing. To get an optimal film, a precise control of input gas composition and also a deposition in a low temperature range from 350 to 400°C are necessary.

ZrO2 thin films were deposited at 1 atm on Si substrates by oxidation-assisted thermal decomposition of zirconium-trifluoroacetylacetonate in the temperature range of 300–615 °C. Above a deposition temperature of 400 °C, the deposited thin films have a columnar grain structure, where each grain is perpendicular to the substrate surface with a c-axis preferred crystallographic orientation, and have poor electrical characteristics as a dielectric thin film. But the thin film deposited at 350 °C has a fine equiaxed microcrystalline structure and has superior electrical characteristics of a breakdown field of 1 MV/cm and a relative dielectric constant of 27.

Carbon nanotubes (CNTs) were grown using a dc arc discharge process and relevant process parameters were investigated. Unlike the usual process in which a carbon anode is filled with metal catalyst powder, CNTs were prepared using a carbon cathode on which the metal catalyst had been deposited using an electroplating system. Various transition metals, Ni, Co and Ti, were used as a catalyst. The results show that multi-walled carbon nanotubes (MWNTs) and single-walled carbon nanotubes (SWNTs) can both be synthesized using this technique. And yield and morphology of the prepared CNTs varied depending on the experimental condition and catalyst. While MWNTs were produced in the deposit and soot sample, SWNTs with diameters near 1nm were only detected in the soot collects. When Ni film was used as a catalyst, the yield of SWNTs was higher than in case of using Co or Ti film as a catalyst. From these results, the optimized preparing condition of CNTs and the properties of a good catalyst are discussed.

We investigated the effect of substrate surface roughness on c-axis preferred orientation of ZnO films deposited by radio frequency (rf) magnetron sputtering. We used as substrates a bare Si(100), evaporated Au/Si(100), evaporated Al/Si(100), and sputtered Al/Si(100), of which rms roughness by atomic force microscope (AFM) were 0.127, 1.71, 2.11, and 6.5∼11.8 nm, respectively. The crystallinity and the c-axis preferred orientation of ZnO films strongly depended on the surface roughness of the used substrates.

MgO and Mg1-xTixO thin films were deposited by the electrostatic spray deposition method using Mg(tmhd)2 and Ti(OiPr)2(tmhd)2 as source materials and tetrahydrofuran and 1-octyl alcohol as solvents. The refractive index of the films shows a strong change from 1.73 for MgO to 2.39 for TiO2. The optical band gap energy values are 3.83 eV for TiO2 film and higher than 5.1 eV for films of Mg/(Mg+Ti) > 0.67. The discharge voltage and current increased with a content of Ti in Mg1-xTixO films. All these changes are closely associated with different Mg/(Mg+Ti) ratios of the films.

Carbon-containing silicon oxide (SiOC) is regarded as a potential low dielectric constant (low-κ) material for an interlayer dielectric (ILD) in next generation interconnection. In this study, we present the fundamental film properties and integration process compatibility of the low-κ SiOC film deposited by using bistrimethylsilylmethane (BTMSM) precursor. As more carbon was incorporated into film, both film density and dielectric constant decreased. The lowest κ-value, which we have obtained in this study, was 2.3 and the hardness of SiOC film was 1.1GPa as well as showing the thermal stability up to 500°C. In case of using conventional gases, organic components in SiOC film restricted etch rate. However, O2 addition could make it possible to obtaine a reasonable etch rate. The post-treatment of SiOC film in hydrogen plasma improved the resistance to O2 plasma in ashing process. The compatibility of SiOC film to the CMP process was also examined.

Ru thin films were deposited on SiO2/Si and (Ba,Sr)TiO3 [BST]/Pt/TiO2/SiO2/Si substrates using Ru(C2H5C5H4)2 [Ru(EtCp)2] by metal-organic chemical vapor deposition (MOCVD). To determine the effects of the solvent, C4H8O [tetrahydrofuran: THF], it was injected into the reaction chamber by the Direct Liquid Injection (DLI) system while Ru(EtCp)2 was input through the bubbler system. Also, Ru thin films were deposited using a liquid source, Ru(EtCp)2 dissolved in THF, delivered by the DLI system. The surface of the Ru thin films deposited on the BST substrate using only Ru(EtCp)2 through the bubbler system was very rough and milky, but the addition of THF made the surface of the films smooth and clean. In addition, Ru films deposited at 325°C using Ru(EtCp)2 dissolved in THF through the DLI system have a dense and smooth microstructure with resistivity as low as 15µωcm.

(Bi,La)4Ti3O12(BLT) thin films were prepared on Si(100) substrates by the pulse injection metalorganic chemical vapor deposition (MOCVD) process, in which Ti and La precursors were injected with periodic pauses while Bi precursor was supplied continuously. In case of the pulse injection method, the film composition was relatively uniform and the Bi content at the interface was relatively uniform and the Bi content at the interface was increased. The BLT films, which were deposited by the pulse injection MOCVD, showed better crystallinity and thinner ionterfacial amorphous layer than the continuous BLT films. The continuous BLT films, although measured at 1 MHz showed similar C-V characteristics to those measured at low frequency region, and their flatband voltages also shifted severely to the negative voltage direction. On the other hand, the pulse BLT films exhibited clockwise ferroelectric hysteresis in the C-V curves. The memory window and the leakage current density were about 2V and 1.46×10−7 A/cm2 at 9V (180 kV/cm), respectively.

We investigated the effects of the substrate temperature (Ts) on the crystallization and the development of texture of Mn-Zn ferrite thin films on SiO2/Si (100) under ion bombardment during ion beam sputtering. As-deposited films showed ferrimagnetic properties in spite of their crystallographic structure of wustite. The crystallographic structure of as-deposited films changed from (111) wustite structure to (222) spinel structure as oxygen partial pressure increased. The (222) preferred orientation seems to originate from oxygen-deficit ambient and preferential resputtering of oxygen ions in films during sputtering. The interplanar distance of the films deposited without oxygen flow decreased with increasing Ts due to release of compressive stress. The saturation Magnetization (Ms) of the film had maximum value at about 275°C, while the resistivity was almost of the same value irrespective of Ts. The unusual fact that crystallization and preferred orientation were less progressed at higher Ts was discussed.

WSix thin films were deposited on SiO2/Si substrates by Low Pressure Chemical Vapor Deposition (LPCVD) using WF6 and SiH4 gases. The deposition mechanism has been studied by measuring the thickness, resistivity and composition of the films by varying deposition temperature and gas flow rate at a constant total reactant gas pressure. Below 300°C, the surface chemical reaction was the rate-limiting process and the deposition rate increased exponentially with temperature having a thermal activation energy of 3.2 kcal/mol. Meanwhile, above 300°C the reaction was governed by the mass transfer step in the gas. The deposition rate in this range is insensitive to the deposition temperature but shows dependence of the flow rate of reactant gases. AES and RBS analyses were performed to determine the stoichiometry of WSix thin film. The Si content in film gradually increased as the deposition temperature increased. The resistivity of as-deposited WSix film has dependence on both deposition temperature and Si/W ratio, and exponentially increased with a moderate slope. However, temperature insensitive behavior of resistivity appeared in the mass transfer controlled region. Such resistivity changes with temperature were discussed with the Si/W ratio and the microstructure of films.