Low temperature oxide formation is an important process in the fabrication of thin-film transistors (TFT) used in active-matrix liquid crystal displays. However, low temperature oxide is prone to have defects at the SiO2/polycrystalline–SiGe interfaces. We have recently developed a novel rf (radio frequency) plasma oxidation method for polycrystalline SiGe (poly-SiGe) materials. The poly-SiGe wafers are oxidized in an oxygen rf plasma with the samples electrically floating. That is, the sample voltage is the same as the sheath potential of the floating wall and is always negative with respect to the bulk of the plasma since electrons have higher mobility than ions. The slightly negative potential on the wafers attracts low energy oxygen ions from the plasma and the resulting damage on the wafers is thus lower than that induced by the more commonly used and energetic electron cyclotron resonance (ECR) source. No deliberate heating is applied during oxidation since the samples are heated spontaneously by the plasma, but the temperature is measured to be below 100 °C throughout the entire process. The oxidation rate is comparable to that of ECR plasma oxidation. Depth profiles are acquired by Auger electron spectroscopy and the interfaces are examined by x-ray photoelectron spectroscopy. The n-channel metal oxide silicon device fabricated on the as-grown gate oxide shows good electrical characteristics. The process is thus compatible with inexpensive large-area, low-temperature fabrication of TFTs on glass substrates.

Boron segregation in an implanted arsenic profile in Si during annealing was investigated under various annealing conditions. It was found that both the implant damage created by arsenic implantation and arsenic deactivation enhance the diffusion of the embedded boron layer toward the shallow As implanted profile. The segregation phenomenon was observed in both 650 °C furnace annealed (FA) and 1000 °C rapid thermally annealed (RTA) samples. For the 650 °C FA sample, the boron segregation peak was located at the junction formed by implanted As, where residual dislocation loops at the original amorphous/crystalline (a/c) interface were also observed. However, no a/c interface dislocation loops were found to be present for the RTA samples. Additional anomalous boron segregation was observed for the 1000 °C RTA+750 °C FA samples. The additional boron segregation is not correlated with defect layers. It is, therefore, concluded that the anomalous boron segregation is caused by the electric field resulting from the formation of a p-n junction.

One-dimensional ZnO nanostructures have been in situ grown on the conductive brass substrate by directly heating the Cu0.70Zn0.30 alloy foils in O2/Ar at 550−900 °C. The growth process and products have been well characterized by means of X-ray diffraction, Raman scattering, electron microscopy, X-ray photoelectron, and photoluminescence spectroscopy. The results indicate that more Zn species is lost from the brass foils at the higher temperatures. Zn species is exhausted, and a sharp diffraction peak shift appears around 750 °C due to the quick depletion. The structures of the ZnO products have been systematically regulated and the more oxygen vacancy is associated with the higher reaction temperature. The correlation in between the oxygen vacancy concentration and the green and exciton emission for these products has been experimentally demonstrated and well understood, which is important for luminescence applications.

Plasma immersion ion implantation (PIII) is an excellent surface modification technique because it is not restricted by the line-of-sight limitation that plagues conventional beamline ion implantation. However, the lack of in situ monitoring has hampered wider acceptance of the technique in industry. It is known that the implantation temperature has a large influence on the surface properties of the treated specimens in addition to the more obvious parameters such as implantation voltage, pulse duration, pulsing frequency, and so on. Direct measurement of the target temperature is complicated by the sample high voltage as well as by interference from the electromagnetic field and plasma. In this article, we present a novel interference-free, in situ temperature measurement technique employing a shielded thermocouple directly attached to the sample stage. Our experiments show that the setup can monitor the target temperature in real time, even under severe arcing conditions. Our results also indicate that in a hot filament glow discharge radiation heating is quite small, and sample heating is primarily caused by ion bombardment during the PIII cycles. The new design will open up other possibilities such as in situ dose monitoring if, for example, the thermocouple is replaced by a Faraday cup.

In this Japanese study, the mean age of ischemic stroke onset increased, while the initial neurological severity at presentation decreased, over a 12-year period. (Circ J 2016; 80: 2033-2036).

Plasma immersion ion implantation (PIII) into slender cylindrical bores with higher efficiency is described in this letter. The use of an inner end plasma source excited by a radio-frequency hollow cathode is investigated theoretically and experimentally. The end source that is covered by a small grounded shielding electrode to ensure steady discharge enables continuous delivery of the required plasmas, and the potential difference in the tube increases the ion impact energy. Particle-in-cell simulation demonstrates that the ion trajectories are complex due to the special electric field configuration that is composed of three regions characterized by ion acceleration, no electric field, and ion deceleration. The end source structure with the open shielding electrode is insufficient to achieve high ion energy, although it is effective in maintaining a steady discharge in the source. Hence, a shielding electrode with a protruding electrode structure is required to conduct high energy PIII; a cylindrical bore with an inner diameter of 20 mm is successfully implanted.

Abstract Plasma ion implantation and deposition of polymeric materials has gained substantial interest in recent years. This paper will present numerical results on initial potential on top surface and some examples on ion implantation of thin polymer foils. The results demonstrate that the thickness and permittivity of treated samples have a critical influence on initial potential drop across the insulating objects. The smaller thickness and larger permittivity are beneficial for ion implantation. Duplex films of Al 2 O 3 /SiO 2 have been fabricated using arc plasma ion implantation and deposition. The films may substantially increase atomic‐oxygen resistance of Kapton foils, which have been frequently utilized in satellites in low‐earth‐orbit (LEO) environment. The mass loss of treated samples may decrease by one quarter of magnitude compared to that of control sample. The PET foils have also been implanted using C 2 H 2 plasma ion implantation. The experimental results show that ion implantation may effectively enhance the gas barrier capability. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Coimplantations of carbon and one of the group II acceptors, Mg, Zn, or Cd, were performed and compared to implantations involving only a single element (Mg, Zn, or Cd) or Ga and C coimplanted into GaAs substrates. The group II and C (II/C) coimplantations act to balance the crystal stoichiometry since group II atoms prefer to reside in the Ga sublattice and C prefers to reside in the As sublattice. The electrical characteristics of the various implantations were obtained from sheet and differential Hall measurements. Rutherford backscattering spectrometry was employed to determine the amount of implantation-induced damage which was then correlated to the amount of C activation in the group II/C coimplanted samples. It was found that coimplantation of the heavier group II acceptors, Zn and Cd, resulted in layers with larger peak hole concentrations. This is a result of the large amount of lattice damage created by these elements which is thought to provide the necessary abundance of As vacancies for C activation. Secondary ion mass spectroscopy measurements of the samples after implant activation indicate that C coimplantation significantly reduces the diffusivity of the group II acceptors. Cross-sectional transmission electron microscopy indicated a unique defect structure (extrinsic dislocation loops) for the cases of group II/C coimplantation. These dislocation loops are located at the diffusion front of the group II element in the samples and therefore have a rather profound influence on the diffusion of the group II elements. A rationalization of the defect structure and the effect it has on the diffusion of group II elements is given.

Among atrial fibrillation (AF) patients, Danish nationwide registries (2011-2015) were used to examine temporal trends of initiation patterns of oral anticoagulation (OAC) treatment according to age. Overall, 43,299 AF patients initiating vitamin K antagonists (VKA) (42%), dabigatran (29%), rivaroxaban (13%), or apixaban (16%) were included with mean age (SD) 72.1 (11.3), 71.5 (11.0), 74.3 (11.1), and 75.3 (11.1) years, respectively. Patients aged ≥85 years comprised 15%. Trend tests showed increase in patients ≥85 years initiating OAC (p < 0.0001). VKA usage decreased from 92% to 24% (p < 0.0001). This decrease was independent of age. Dabigatran was the most common non-VKA OAC (NOAC) (40% users), but usage decreased from 2014 until study end (6%) (p < 0.0001). Apixaban was the most used OAC at study end (41%), in particular among those ≥85 years (44%). Compared with patients aged <65 years, the odds ratios associated with initiating VKA, dabigatran, rivaroxaban, or apixaban for patients aged ≥85 years were 0.81 (95% CI 0.75-0.86), 0.65 (95% CI 0.60-0.70), 1.52 (95% CI 1.38-1.67), and 2.09 (95% CI 1.89-2.30), respectively. In conclusion, substantial increase in NOAC usage has occurred. Increasing age was associated with upstart of rivaroxaban or apixaban with reference to age <65 within the specific agent.

We have investigated the thermal stability of surface structures of tetrahexahedral platinum nanoparticles surrounded by high-index facets such as (730), (210), (310), and (520) by molecular dynamic simulation. The instantaneous atomic configurations, mean-squared displacement, radical distribution function, and average energy per atom are studied. At the lower temperature range, that is, 0∼860 K, both surface atoms and interior atoms oscillate around their equilibrium positions slightly and the high-index surface steps at which chemical reactions usually take place are maintained regularly. If the temperature is raised above 860 K, surface diffusion becomes dramatic and those surface steps disappear, though the general shape of the nanoparticles is still retained to a high temperature of 1100 K or so. Based on this study, the improved catalysis of Pt nanoparticles can be maintained only at temperatures lower than 860 K.

Abstract Purpose/Background : Oral anticoagulation is recommended for stroke prevention in patients with non-valvular atrial fibrillation (NVAF) and stroke risk factors, but discontinuation rates are high among those treated with vitamin K antagonists (VKA). After the first year of treatment, about half of patients permanently stop taking VKA therapy. We examined persistence to therapy with dabigatran etexilate (DE) in patients enrolled in the global, prospective GLORIA-AF Registry Program. Methods: GLORIA-AF collects data in three phases from routine clinical practice in 44 countries worldwide. Enrollment in Phase II was initiated following approval of DE, the first non-VKA oral anticoagulant (NOAC) available. During this phase, all patients with newly diagnosed NVAF at risk for stroke starting DE are followed for 2 years. This analysis is based on a pre-specified interim analysis once follow-up of the first 3000 DE patients was completed. Patients were recruited between November 2011 and December 2013 at nearly 1,000 sites worldwide, by cardiologists, neurologists and general practitioners. To reduce selection bias, patients were recruited consecutively, irrespective of antithrombotic therapy. Persistence was defined as time from initiation to discontinuation of therapy for &gt;30 days or substitution of initial treatment by another oral anticoagulant. Persistence rates were analyzed on the basis of a time-to-event analysis using the Kaplan Meier method. Results: Among eligible patients, 2,937 were prescribed DE; 823 (27.4%) in North America, 1,503 (50.1%) in Europe, 194 (6.5%) in Latin America, 54 (1.8%) in Africa/Middle East and 363 (12.1%) in Asia. Overall, 55.3% were male, the median age was 71.0 (range 23-98) years; 36.7% were ≥75 years old. The CHA2DS2VASc score was ≥2 in 88.2%, 78.9% had hypertension, 22.7% diabetes mellitus, 10.1% prior stoke and 24.9% heart failure. All but 5 eligible patients took at least one dose of DE. The probability of remaining on DE treatment was 76.6% at 1 year and 69.2% at 2 years (based on Kaplan-Meier method). At the 2 years visit, half of the permanently discontinued patients (418 out of 828) had switched to another oral anticoagulant. Characteristics of patients discontinuing vs. sustaining therapy and relationships to stroke risk and geographical region will be presented. Conclusions: In this global, prospective, cohort of patients newly diagnosed with NVAF and treated with DE, persistence on therapy was high through 2 years of treatment, with an estimated probability of remaining on treatment of about 77% after 1 year and 70% after 2 years. The detailed results will provide a global perspective on the factors that influence treatment persistence in patients prescribed a NOAC for stroke prophylaxis. Disclosures Teutsch: Boehringer Ingelheim: Employment. Huisman:Boehringer Ingelheim Pharma GmbH &amp; Co.KG: Other: Grant support; GlaxoSmithKline: Other: Grant support; Bayer HealthCare: Other: Grant support; Pfizer: Other: Grant support; Actelion: Other: Grant support. Lip:Bayer, BMS/Pfizer, Boehringer Ingelheim and Sanofi Aventis: Speakers Bureau; Bayer, Astellas, Merck, Sanofi, Bristol-Myers Squibb (BMS)/Pfizer, Daiichi-Sankyo, Biotronik, Portola and Boehringer Ingelheim: Consultancy. Diener:AstraZeneca, Boehringer Ingelheim, GlaxoSmithKline, Janssen-Cilag, Lundbeck, Novartis, Sanofi Aventis, Syngis and Talecris: Research Funding; Abbott, Allergan, AstraZeneca, Bayer Vital, BMS, Boehringer Ingelheim, CoAxia, Corimmun, Covidien, Daiichi-Sankyo, D-Pharm, Fresenius, GlaxoSmithKline, Janssen-Cilag, Johnson &amp; Johnson, Knoll, Lilly, Medtronic, MindFrame, MSD, Neurobiological Technologies: Honoraria; The Department of Neurology at the University Duisburg-Essen received research grants from the German Research Council (DFG), German Ministry of Education and Research (BMBF), European Union, National Institutes of Health, Bertelsmann Foundation and Heinz: Research Funding. Dubner:steering committee member for Boehringer Ingelheim: Consultancy; St Jude Medical: Research Funding. Changsheng:steering committee member for Boehringer Ingelheim: Consultancy. Rothman:RTI Health Solutions: Employment. Zint:Boehringer Ingelheim: Employment. Elsaesser:Boehringer Ingelheim: Employment. Paquette:Boehringer Ingelheim: Employment. Bartels:Boehringer Ingelheim: Employment. Halperin:Bayer HealthCare: Consultancy; Boehringer Ingelheim: Consultancy.