• Journal of Technology Innovation
• /
• v.5 no.1
• /
• pp.1-14
• /
• 1997

Firms prefer in some specific conditions cooperative R&D to non-cooperative for developing technology. Previous studies on the conditions show firms want to choose cost-sharing type of cooperative R&D (the CS-RJV) rather than non-cooperative one when target technology is either 'relatively easy' or 'relatively difficult', and to join multiple-research or pararell-research type of cooperation (the PR-PJV) than to compete each other if technology is only 'relatively easy'. However, by introducing technological leakage as well as difficulty of technology. it is shown that this seemingly contrasted phenomenon almost disappears ; the PR-RJV can be also preferred by firms even is case of 'relatively difficult' technology only if there exists some extent of a technological leakage.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.50 no.1
• /
• pp.24-29
• /
• 2001

PZT thin films(4000A) have prepared onto 1737 corning glass and ITO coated glass substrates with a RF magnetron sputtering system using Pb_{1.05}(Zr_{0.52},Ti_{0.48})O_3$ceramic target, Electrical properties of PZT thin film deposited after ITO coated glass were P${\gamma}$ was decreased by 25% after 109cycles, respectively. With the RTA treatment duration and temperature increased, the crystallization of PZT thin films were enhanced, however, the leakage current density became higher. The leakage current mechanism was found to be space charge conduction by the defects and oxygen vacancies existing in PZT and PZT/bottom electrode interfaces.

• Korean Journal of Materials Research
• /
• v.3 no.5
• /
• pp.482-496
• /
• 1993

Radiation damage and contamination of silicons etched in the $CF_4+H_2$ and $CHF_3$ magnetron discharges have been characterized using Schottky diode characteristics, TEM, AES, and SIMS as a function of applied magnetic field strength. It turned out that, as the magnetic field strength increased, the radiation damage measured by cross sectional TEM and by leakage current of Schottky diodes decreased colse to that of wet dtched samples especially for $CF_4$ plasma etched samples, For $CF_4+H_2$and $CHF_3$ etched samples, hydrogen from the plasmas introduced extended defects to the silicon and this caused increased leakage current to the samples etched at low magnetic field strength conditions by hydrogen passivation. The thickness of polymer with the increasing magnetic field strength and showed the minimum polymer residue thickness near the 100Gauss where the silicon etch rate was maximum. Also, other contaminants such as target material were found to be minimum on the etched silicon surface near the highest etch rate condition.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.07b
• /
• pp.570-573
• /
• 2002

Pb(Zr0.52Ti0.48)O3 (PZT) thin films were deposited on the Pt/Ti bottom electrode by rf magnetron sputtering method from target containing 5%, 25% and 50% Pb excess for applying ferroelectric random access memory (FRAM). PZT films were deposited at $300^{\circ}C$ and then they were crystallized by rapid thermal annealing (RTA) at $700^{\circ}C$. After RTA treatment, our results showed that all PZT films indicated perovskite polycrystalline structure with preferred orientation (110) and no pyrochlore phase was observed by X-ray diffraction (XRD) and by Scanning electron microscopy (SEM). A well-fabricated PZT film of excess Pb 25% capacitor showed a leakage current density in the order of $2.63{\times}10^{-7}A/cm^2$ at 100kV/cm, a remanent polarization of $3.385{\mu}C/cm^2$ and a coercive field of 41.32 kV/cm. The results showed that Pb excess of target affects to electrical properties of PZT thin film.

• Journal of the Microelectronics and Packaging Society
• /
• v.11 no.3 s.32
• /
• pp.91-97
• /
• 2004

PBT thin films were formed by rf-magnetron sputtering on $Pt/Ti/SiO_2/Si$ substrate. Bulk-PZT target containing $5\%$-excess PbO was used. After PZT thin films had been deposited at room temperature, remaining portion of the thin film was formed by in-situ process. The ferroelectric perovskite phase was formed at $650^{\circ}C$. The leakage current property was improved dramatically by 2-step sputtering, and in the sample containing optimum thickness of room temp.-layer very low leakage current of $2{\times}10^{-7}A/cm^2$ was shown. As a result of the investigation on the leakage current mechanism, the electrical conduction mechanism in all PZT thin films formed by several conditions was confirmed as bulk-limited mechanism.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2020.05a
• /
• pp.455-457
• /
• 2020

Recent studies demonstrate that deep learning model is easily biased by trained with unbalanced datasets. For example, the deep network can be trained to make a prediction by background feature instead the real target's feature. For those problem, a measurement called leakage was introduced to digitize this tendency. In this paper, we propose augmentation strategy which are used generally in computer vision problem to remedy this bias problem and we showed a simple augmentation methods have a effect to this task with experiments.

• Journal of Korean Vacuum Science & Technology
• /
• v.2 no.2
• /
• pp.92-96
• /
• 1998

Ferroelectric Bi-layered oxides SrBi2Ta2O9 (SBT) thin films have been deposited on Pt/Ti/SiO2/Si substrates using multi-target sputtering. Structure, composition, and electrical properties have been investigated on films. The SBT films were deposited with the various bismuth sputtering powers. The SBT films deposited with the bismuth sputtering power of 20 W have the most dense microstructure and the remanent polarization (Pr) of 9.2 ${\mu}$C/cm and the coercive field (Ec) of 43.8 kV/cm at an applied voltage of 5V. The SBT films deposited with the bismuth sputtering power of 20W showed a fatigue-free characteristics up to 1.0${\times}$1010 cycles under 5V bipolar pulse and a leakage current density of 2.0${\times}$10-8 A/$\textrm{cm}^2$ at 200 kV/cm.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2005.09a
• /
• pp.106-109
• /
• 2005

The ITO thin films for Top-Emitting Organic Light Emitting Devices (TOLEDs) were prepared on cell(LiF/Organic Layer/Bottom Electrode : ITO ) by FTS (Facing Targets Sputtering) system under different sputtering conditions which were varying gas pressure, input current and distance of target to target($D_{T-T}$). As a function of sputtering conditions, I-V characteristics of prepared ITO thin films on cell were measured by 4156A (HP). In the results, when the In thin films were deposited at $D_{T-T}$ 70mm and working pressure 1mTorr, the leakage current of ITO/cell was about 11[V] and 5E-6[$mA/cm^2$].

• The Journal of Engineering Geology
• /
• v.28 no.2
• /
• pp.217-246
• /
• 2018

During the selection and characterization of target formations in the Small-scale Offshore $CO_2$ Storage Demonstration Project in the Pohang Basin, we have carefully investigated the possibility of induced earthquakes and leakage of $CO_2$ during the injection, and have designed the storage processes to minimize these effects. However, people in Pohang city have a great concern on $CO_2$-injection-intrigued seismicity, since they have greatly suffered from the 5.4 magnitude earthquake on Nov. 15, 2017. The research team of the project performed an extensive self-investigation on the safety issues, especially on the possible $CO_2$ leakage from the target formation and induced earthquakes. The target formation is 10 km apart from the epicenter of the Pohang earthquake and the depth is also quite shallow, only 750 to 800 m from the sea bottom. The project performed a pilot injection in the target formation from Jan. 12 to Mar. 12, 2017, which implies that there are no direct correlation of the Pohang earthquake on Nov. 15, 2017. In addition, the $CO_2$ injection of the storage project does not fracture rock formations, instead, the supercritical $CO_2$ fluid replaces formation water in the pore space gradually. The self-investigation results show that there is almost no chance for the injection to induce significant earthquakes unless injection lasts for a very long time to build a very high pore pressure, which can be easily monitored. The amount of injected $CO_2$ in the project was around 100 metric-tonne that is irrelevant to the Pohang earthquake. The investigation result on long-term safety also shows that the induced earthquakes or the reactivation of existing faults can be prevented successfully when the injection pressure is controlled not to demage cap-rock formation nor exceed Coulomb stresses of existing faults. The project has been performing extensive studies on critical stress for fracturing neighboring formations, reactivation stress of existing faults, well-completion processes to minimize possible leakage, transport/leakage monitoring of injected $CO_2$, and operation procedures for ensuring the storage safety. These extensive studies showed that there will be little chance in $CO_2$ leakage that affects human life. In conclusion, the Small-scale Offshore $CO_2$ Storage Demonstration Project in the Pohang Basin would not cause any induced earthquakes nor signifiant $CO_2$ leakage that people can sense. The research team will give every effort to secure the safety of the storage site.

• Nuclear Engineering and Technology
• /
• v.53 no.6
• /
• pp.1970-1978
• /
• 2021

The aim of this study was to optimize the target, moderator, and collimator (TMC) in a neutron beam generator for the accelerator-based BNCT (A-BNCT) system. The optimization employed the Monte Carlo Neutron and Photon (MCNP) simulation. The optimal geometry for the target was decided as the one with the highest neutron flux among nominates, which were called as angled, rib, and tube in this study. The moderator was optimized in terms of consisting material to produce appropriate neutron energy distribution for the treatment. The optimization of the collimator, which wrapped around the target, was carried out by deciding the material to effectively prevent the leakage radiations. As results, characteristic of the neutron beam from the optimized TMC was compared to the recommendation by the International Atomic Energy Agent (IAEA). The tube type target showed the highest neutron flux among nominates. The optimal material for the moderator and collimator were combination of Fluental (Al₂0₃+AlF₃) with ⁶⁰Ni filter and lead, respectively. The optimized TMC satisfied the IAEA recommendations such as the minimum production rate of epithermal neutrons from thermal neutrons: that was 2.5 times higher. The results can be used as source terms for shielding designs of treatment rooms.