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This study presents the development of a ferrite core inductively coupled plasma (ICP) radio frequency (RF) ion source designed to improve the lifetime of ion sources in commercial ion implanters. Unlike existing DC methods, this novel approach aims to enhance the performance and lifetime of the ion source. We constructed a high-vacuum evaluation chamber to thoroughly examine RF ion source characteristics using a Langmuir probe. Comparative experiments assessed the extraction current of two upgraded ferrite core RF ion sources in a commercial ion implanter setting. Additionally, we tested the plasma lifetime of the ICP source and took temperature measurements of various components to verify the operational stability and efficiency of the innovative design. This study confirmed that the ICP RF ion source operated effectively under a high vacuum of 10-5 torr and in a high-voltage environment of 30 kV. We observed that the extraction current increased linearly with RF power. We also confirmed that BF3 gas, which presents challenging conditions, was stably ionized in the ICP RF ion sources.
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The influence of nanoparticle (NP) size on the physical characteristics of sintered silver NP ink was studied using four different types of inks. The Ag NP inks were spin-coated on glass substrates with an average thickness of 300 nm. Each sample was sintered for 30 min, with temperatures from 50 °C to 400 °C by an interval of 50 °C. After sintering, the specific resistance of each case was obtained using the resistance and surface profile measurements. The minimum specific resistance obtained by the experiment was 2.6 µΩ·cm in the case in which 50 nm-sized Ag NP ink was sintered at 350 °C. The transformed surface morphology and grain size of each case were observed using scanning electron microscopy and atomic force microscopy. The results of this study can be a reference for future manufacturers in selecting the Ag NP size and the sintering temperature.
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Thin transparent oxide layers are typically patterned for use in electronic products including semiconductors, displays, and solar cells for applications such as transparent electrodes, insulating films, and encapsulation films. Conventional patterning methods have traditionally been used in photolithography and lift-off processes. Photolithography employs the wet development process, which has disadvantages such as potential undercut effects, swelling, chemical contamination, and high process costs. On the other hand, laser ablation, which has the advantages of high accuracy, high speed, a noncontact nature, and selective processing, can be used to pattern thin films. However, absorption in transparent oxide films is usually low. In this study, experiments were conducted to determine the ablation characteristics of mask layers. The factors affecting ablation, including beam radii, fluences, overlap ratios, and coating thicknesses, were examined; and the parameters characteristic of residue-free ablation, namely the ablation threshold, minimum fluence, and minimum ablation linewidth, were also examined. The experimental results revealed that the beam radius was an important parameter in determining the resolutions of transparent films and substrates.
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OBJECTIVES: Use of proton pump inhibitors (PPIs) is a mainstay in treating upper gastrointestinal bleeding (UGIB). However, the beneficial effects of PPIs are not anticipated to extend beyond the duodenum and may actually contribute to the risk of lower gastrointestinal bleeding (LGIB). However, in practice, PPIs are often used for inpatients with LGIB where no benefit exists. METHODS: A retrospective chart review was performed on inpatients during a 2-year period at an urban academic teaching hospital. Inpatients with consults to the gastroenterology (GI) service with confirmed or highly suspected LGIB were included. Outcomes regarding PPI use and the GI consulting service recommendations in these 225 patients were evaluated. RESULTS: About 37.8% of patients were started on a PPI during their inpatient course. Of those, 46% patients started on a PPI had no indication for PPI and 85% had no recommendation by the GI consultants to start a PPI. Of the 85 patients started on PPI, the GI consultants recommended stopping it in two (2.3%) patients. Lastly, 20 patients (9%) were discharged on PPI without an indication for PPI. CONCLUSION: To our knowledge, this is the first study that looked at the inappropriate utilization of PPIs in patients admitted for LGIBs utilizing GI consultant recommendations. Given the large proportion of patients started on PPI without a clinical indication and continued at discharge and the paucity of GI recommendations to discontinue inappropriate use, we found that clinical care may be improved with formal GI recommendations regarding use of PPI.