• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.339.1-339.1
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• 2016

본 연구에서는 금속-절연막-반도체 (MIS) 형태를 이용한 비휘발성 메모리 (NVM) 소자의 메모리 특성 향상을 위해 수소화 (Hydrogenation) 처리된 게이트산화막을 블로킹 산화막으로 응용하였다. 기존 연구의 경우 저온 공정시 게이트산화막의 고품위 전기적 특성 확보에 어려움이 있었다. 하지만 이번 연구에서는 게이트산화막 형성 시 H2 또는 NH3가스를 함께 주입시켜 Si-H 결합의 증대를 통한 passivation 효과를 얻을 수 있었다. 형성된 게이트산화막의 전기적 특성을 확인하기 위해 우선적으로 박막트랜지스터 (TFT)를 제작하여 전기적 특성을 확인하였다. 수소화 처리된 게이트산화막을 이용한 TFT 경우 그렇지 않은 게이트산화막을 이용한 TFT 보다 약 5V의 threshold voltage (Vth) 이득이 있으며 Vth의 hysteresis 특성 역시 거의 0V로 매우 안정적이었다. MIS 형태의 NVM 소자의 경우 -20V에서 +15V, +15V에서 -20V로 sweep하여 측정한 flatband voltage (Vfb)의 변화량 역시 약 88%의 메모리 특성 이득이 있음을 확인하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.566-569
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• 2001

In this paper, we investigated the electrical characteristics through DC power at manufacturing the MIS capacitor insulator AIN thin film based on reactive sputtering method. In case of deposition temperature 250$^{\circ}C$, pressure 5mTorr, total flow rate 8sccm(Ar:4sccm N2:4sccm), AIN thin film was deposited with changing DC power. As DC power increses, resistivity is observed a little increase. When AIN thin film is deposited at 100W, the result shows leakage current 10$\^$-8/A/$\textrm{cm}^2$ at 0.1MV/cm. Otherwise, In case of depositing at 150W and 200W, the result shows that the characteristic of leakage current is under 10$\^$-9//$\textrm{cm}^2$ at 0.1MV/cm. In C-V characteristic with DC power, deep depletion phenomenon is observed at inversion region in 100W and 150W. In 200W, that phenomenon, however, was showed to decrease. It shows that the hysterisis increases with being increasing DC power.

• The korean journal of orthodontics
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• v.42 no.1
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• pp.4-10
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• 2012

Objective: To determine the effect of surface anodization on the interfacial strength between an orthodontic microimplant (MI) and the rabbit tibial bone, particularly in the initial phase aft er placement. Methods: A total of 36 MIs were driven into the tibias of 3 mature rabbits by using the self-drilling method and then removed aft er 6 weeks. Half the MIs were as-machined (n = 18; machined group), while the remaining had anodized surfaces (n = 18; anodized group). The peak insertion torque (PIT) and the peak removal torque (PRT) values were measured for the 2 groups of MIs. These values were then used to calculate the interfacial shear strength between the MI and cortical bone. Results: There were no statistical differences in terms of PIT between the 2 groups. However, mean PRT was significantly greater for the anodized implants ($3.79{\pm}1.39$ Ncm) than for the machined ones ($2.05{\pm}1.07$ Ncm) (p < 0.01). The interfacial strengths, converted from PRT, were calculated at 10.6 MPa and 5.74 MPa for the anodized and machined group implants, respectively. Conclusions: Anodization of orthodontic MIs may enhance their early-phase retention capability, thereby ensuring a more reliable source of absolute anchorage.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.2
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• pp.107-112
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• 2005

We present an AlGaN/GaN metal-insulator-semiconductor-heterostructure field effect transistor (MIS-HFET) with an $Al_2O_3-HfO_2$ laminated high-k dielectric, deposited by plasma enhanced atomic layer deposition (PEALD). Based on capacitance-voltage measurements, the dielectric constant of the deposited $Al_2O_3-HfO_2$ laminated layer was estimated to be as high as 15. The fabricated MIS-HFET with a gate length of 102 m exhibited a maximum drain current of 500 mA/mm and maximum tr-ansconductance of 125 mS/mm. The gate leakage current was at least 4 orders of magnitude lower than that of the reference HFET. The pulsed current-voltage curve revealed that the $Al_2O_3-HfO_2$ laminated dielectric effectively passivated the surface of the device.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.29-32
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• 1999

$GaF_3$ films were directly grown on p' and p-type GaAs(100) substrates using a $SF_6$ plasma discharge system. GaAs MIS(Meta1-Insulator-Semiconductor) capacitor was successfully fabricated for about 1 hour at temperature $290^{\circ}C$ using the as-grown $GaF_3$ films. The as-grown films on p'-GaAs exhibited a current density of less than 6.68 $\times$ $1O^{-9}$ A/$cm^2$ at a breakdown field of 500kV/cm and a refractive index of 2.0 ~ 2.3 at a wavelength of 632.8 nm. The dielectric constant was about 5 derived from 1 MHz capacitance-voltage (C-V) measurements. Dielectric dispersion of the fluoridated films on p'-GaAs measured ranged from 100 Hz to 10 MHz was not observed.

• Clinical and Experimental Pediatrics
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• v.64 no.2
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• pp.68-75
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• 2021

The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been spreading worldwide since December 2019. Hundreds of cases of children and adolescents with Kawasaki disease (KD)-like hyperinflammatory illness have been reported in Europe and the United States during the peak of the COVID-19 pandemic with or without shock and cardiac dysfunction. These patients tested positive for the polymerase chain reaction or antibody test for SARS-CoV-2 or had a history of recent exposure to COVID-19. Clinicians managing such patients coined new terms for this new illness, such as COVID-19-associated hyperinflammatory response syndrome, pediatric inflammatory multisystem syndrome temporally associated with COVID-19, or COVID-19-associated multisystem inflammatory syndrome in children (MIS-C). The pathogenesis of MIS-C is unclear; however, it appears similar to that of cytokine storm syndrome. MIS-C shows clinical features similar to KD, but differences between them exist with respect to age, sex, and racial distributions and proportions of patients with shock or cardiac dysfunction. Recommended treatments for MIS-C include intravenous immunoglobulin, corticosteroids, and inotropic or vasopressor support. For refractory patients, monoclonal antibody to interleukin-6 receptor (tocilizumab), interleukin-1 receptor antagonist (anakinra), or monoclonal antibody to tumor necrosis factor (infliximab) may be recommended. Patients with coronary aneurysms require aspirin or anticoagulant therapy. The prognosis of MIS-C seemed favorable without sequelae in most patients despite a reported mortality rate of approximately 1.5%.

• The korean journal of orthodontics
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• v.53 no.5
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• pp.289-297
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• 2023

Objective: To analyze the microimplant (MI) displacement pattern on treatment with a maxillary skeletal expander (MSE) using cone-beam computed tomography (CBCT). Methods: Thirty-nine participants (12 males and 27 females; mean age, 18.2 ± 4.2 years) were treated successfully with the MSE II appliance. Their pre- and post-expansion CBCT data were superimposed. The pre- and post-expansion anterior and posterior inter-MI angles, neck and apical inter-MI distance, plate angle, palatal bone thickness at the MI positions, and suture opening at the MI positions were measured and compared. Results: The jackscrew plate was slightly bent in both anterior and posterior areas. There was no significant difference in the extent of suture opening between the anterior and posterior MIs (P > 0.05). The posterior MI to hemiplate line was greater than that anteriorly (P < 0.05). The apical distance between the posterior MIs was greater than that anteriorly (P < 0.05). The palatal thickness at the anterior MIs was significantly greater than that posteriorly (P > 0.01). Conclusions: In the coronal plane, the angulation between the anterior MIs in relation to the jackscrew plate was greater than that between the posterior MIs owing to the differential palatal bone thickness.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1919-1921
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• 1999

AlN thin films were fabricated by sputter for the application of MIS device with Al/AlN/Si structure. We controled that sub-temperature room-temperature. Sputtering pressure 5 mTorr, flow ratio Ar:$N_2$=1:1(4sccm:4sccm), and appended hydrogen gas $0{\sim}5%$. AlN thin films thickness fabricated to maintain $2700{\AA}$ time control. Before the experiment remove to the contaminated material use the Ultrasonic every 10 minute use the acetone and ethanol, then use the HF remove oxide-substance at 10 second. To analyze characteristic of the $H_2$ gas addition period, C-V and I-V characteristic make and experiment $H_2$ gas at addition period progressive capability of I-V and C-V characteristic.

• Journal of Sensor Science and Technology
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• v.16 no.2
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• pp.97-103
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• 2007

Crystallized carbon nitride film that has many stable physical and/or chemical properties has been expected potentially by a new electrical material. However, one of the most significant problems degrading the quality of carbon nitride films is an existence of N-H and C-H bonds from the deposition environment. The possibility of these reactions with hydroxyl group in carbon nitride films, caused by a hydrogen attack, was suggested and proved in our previous reports that this undesired effect could be applied for fabricating micro-humidity sensors. In this study, MIS capacitor and MIM capacitor with $5{\mu}m{\times}5{\mu}m$ meshes were fabricated. As an insulator, carbon nitride film was deposited on a $Si_{3}N_{4}/SiO_{2}/Si$ substrate using reactive magnetron sputtering system, and its dielectric constant, C-V characteristics and humidity sensing properties were investigated. The fabricated humidity sensors showed a linearity in the humidity range of 0 %RH to 80 %RH. These results reveal that MIS and MIM $CN_{X}$ capacitive humidity sensors can be used for Si based micro-humidity sensors.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.12
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• pp.755-760
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• 1999

Various fluoride films were investigated for a gate insulator of thin film transistor application. Conventional oxide containing materials like $SiO_2\;Ta_2O_5\; and \; Al_2O_3$ exhibited high interface states which lead to an increased threshold voltage and poor stability of TFT. In this paper, we investigated gate insulators using a binary matrix system of fluoride such as $CaF_2,\; SrF_2\; MgF_2,\; and\; BaF_2$. These materials exhibited an improvement in lattice mismatch, interface state and electrical stability. MIM and MIS devices were employed for an electrical characterization and structural property examination. Among the various fluoride materials, $CaF_2$ film showed an excellent lattice mismatch of 5%, breakdown electric field higher than 1.2MV/cm and leakage current density of $10^{-7}A/cm^2$. MIS diode having $Ca_2$ film as an insulation layer exhibited the interface states as low as $1.58\times10^{11}cm^{-2}eV^{-1}$. This paper probes a possibility of new gate insulator materials for TFT applications.