• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.1
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• pp.89-93
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• 2012

c-BN films were deposited on SKH-51 steels by electron assisted hot filament CVD method and microstructure development was studied processing parameters such as bias voltage, temperature, etching and phase transformation at boundary layer between BN compound and steel to develop a high performance wear resistance tools. A negative bias voltage higher than 200V at substrate temperature of $800^{\circ}C$ and gas pressure of 20 torr in B2H6-NH3-H2 gas system was one of optimum conditions to produce c-BN films on the SKH-51 steels. Thin layer of hexagonal boron nitride phase was observed at the interface between c-BN layer and substrate.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.3
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• pp.276-283
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• 2005

Magnetic tunneling transistor (MTT) device using the amorphous n-type Si semiconductor film for base and collector consisting of the [CoFe/NiFe](free layer) and Si(top layer) multilayers was used to study the spin-dependent hot electron magnetocurrent (MC) and tunneling magnetoresistance (TMR) at room temperature. A large MC of 40.2 % was observed at the emitter-base bias voltage ( $V_{EB}$ ) of 0.62 V. The increasing emitter hot current and transfer ratio ( $I_{C}$/ $I_{E}$) as $V_{EB}$ are mainly due to a rapid increase of the number of conduction band states in the Si collector. However, above the $V_{EB}$ of 0.62 V, the rapid decrease of MC was observed in amorphous Si-based MTT because of hot electron spin-dependent elastic scattering across CoFe/Si interfaces.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.3
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• pp.147-151
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• 2016

Graphene has a monolayer crystal structure formed with C-atoms and has been used as a base layer of HETs (hot electron transistors). Graphene HETs have exhibited the operation at THz frequencies and higher current on/off ratio than that of Graphene FETs. In this article, we report on the preliminary results of current characteristics from the HETs which are fabricated utilizing highly doped Si collector, graphene base, and 5 nm thin $Al_2O_3$ tunnel layers between the base and Ti emitter. We have observed E-B forward currents are inherited to tunneling through $Al_2O_3$ layers, but have not noticed the Schottky barrier blocking effect on B-C forward current at the base/collector interface. At the common-emitter configuration, under a constant $V_{BE}$ between 0~1.2V, $I_C$ has increased linearly with $V_{CE}$ for $V_{CE}$ < $V_{BE}$ indicating the saturation region. As the $V_{CE}$ increases further, a plateau of $I_C$ vs. $V_{CE}$ has appeared slightly at $V_{CE}{\simeq}V_{BE}$, denoting forward-active region. With further increase of $V_{CE}$, $I_C$ has kept increasing probably due to tunneling through thin Schottky barrier between B/C. Thus the current on/off ration has exhibited to be 50. To improve hot electron effects, we propose the usage of low doped Si substrate, insertion of barrier layer between B/C, or substrates with low electron affinity.

• Journal of the Korean Ceramic Society
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• v.19 no.2
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• pp.152-156
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• 1982

The behavior of magnesite during hot pressing is studied from 80$0^{\circ}C$ to 110$0^{\circ}C$ by Knoop hardness test, X-ray diffraction and electron microscopy. The growth of magnesia crystallite in magnesite is observed at 110$0^{\circ}C$ and crystallite size is about 2 microns. It is also observed that hot pressing showes enhanced sinterability comparing to ordinary pressure-less sintering. The magnesia body with 95 per cent of theoretical density is obtained by hot pressing at relatively low temperature such as 110$0^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.28 no.7
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• pp.1195-1198
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• 2007

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.479-488
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• 2008

Some biological activities such as an electron donating capacity, the contents of total polyphenol compounds and flavonoids, fibrinolytic activity and $\alpha$-glucosidase inhibitory activity have been detected in hot water extracts of Ligularia fischeri and Angelica gigas Nakai. To increase the usefulness of the functional ingredients for prevention and improvement of some metabolic disorders, ethanol-treated hot water extracts of Angelica gigas Nakai were prepared. A hot water extract of Ligularia fischeri has 92% of electron donating capacity, 39.4 mg/g of total polyphenol compounds, 24.8 mg/g of flavonoids and 29.8% of $\alpha$-glucosidase inhibitory activity, but no fibrinolytic activity. A hot water extract of Angelica gigas Nakai has 94.7% of electron donating capacity, 5.8 mg/g of total polyphenol compounds, 2.6 mg/g of flavonoids, 0.48 plasmin units of fibrinolytic activity and no $\alpha$-glucosidase inhibitory activity. However, with partial purification using cold ethanol treatment, the $\alpha$-glucosidase inhibitory activity of Angelica gigas Nakai was increased to 70.5%. Thus, we expected a more useful effect with the use of the addition of a cold ethanol-treated Angelica gigas Nakai extract. The L, b values of cold buckwheat noodles using a mixture of 0$\sim$3% of Ligularia fischeri powder and 0.5% of an ethanol-treated hot water extract of Angelica gigas Nakai were decreased with the addition of an increasing amount of Ligularia fischeri powder. Among the mechanical qualities, only adhesiveness was significantly higher in 3% Ligularia fischeri noodles. From sensory evaluation data, it was determined that these two functional ingredients did not ruin the color, texture, and overall acceptance of the cold buckwheat noodles. A higher amount of the extracts improved the quality of the product with little added cost.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.3
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• pp.169-172
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• 2020

In this paper, the effect of hot carrier injection on an n-bulk fin field-effect transistor (FinFET) is analyzed. The hot carrier injection method is applied to determine the performance change after injection in two ways, channel hot electron (CHE) and drain avalanche hot carrier (DAHC), which have the greatest effect at room temperature. The optimum condition for CHE injection is V_G=V_D, and the optimal condition for DAHC injection can be indirectly confirmed by measuring the peak value of the substrate current. Deterioration by DAHC injection affects not only hot electrons formed by impact ionization, but also hot holes, which has a greater impact on reliability than CHE. Further, we test the amount of drain voltage that can be withstood, and extracted the lifetime of the device. Under CHE injection conditions, the drain voltage was able to maintain a lifetime of more than 10 years at a maximum of 1.25 V, while DAHC was able to achieve a lifetime exceeding 10 years at a 1.05-V drain voltage, which is 0.2 V lower than that of CHE injection conditions.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.1
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• pp.1-5
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• 2010

In this paper, we directly compare the program efficiency of conventional channel hot electron (CHE) injection methods and a novel hot electron injection methods using substrate forward biases in our silicon-oxide-nitride-oxide-silicon (SONOS) cell. Compared with conventional CHE injection methods, the proposed injection method showed improved program efficiency including faster program operation at lower bias voltages as well as localized trapping features for multi-bit operation with a threshold voltage difference of 1 V at between the forward and reverse read. This program method is expected to be useful and widely applied for future nano-scale multi-bit SONOS memories.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.10
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• pp.32-38
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• 2003

This works reports the measurement and analysis results on the hot electron induced device degradation in Gate-All-Around SOI MOSFET's, which were fabricated using commercially available SIMOX material. It is observed that the worst-case condition of the device degradation in nMOSFETs is $V_{GS}$ = $V_{TH}$ due to the higher impact ionization rate when the parasitic bipolar transistor action is activated. It is confirmed that the device degradation is caused by the interface state generation from the extracted degradation rate and the dynamic transconductance measurement. The drain current degradation with the stress gate voltages shows that the device degradation of pMOSFETs is dominantly governed by the trapping of hot electrons, which are generated in drain avalanche hot carrier phenomena.r phenomena.

• The Korean Journal of Ceramics
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• v.5 no.3
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• pp.224-229
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• 1999

The preparation and toughening of SiC-AIN solid solution from powder mixtures of $\beta$-SiC, AIN and $\alpha$-SiC by hot-pressing were studied in the 1870 to $2030^{\circ}C$ temperature range. The reaction of AIN and $\beta$-SiC(3C) powders causing transformation to the 2H(wurtzite) structure appeared to depend on hot-pressing temperatures and an additive of $\alpha$-SiC. For the composition of 49wt% SiC with 2 wt% $\alpha$-SiC and 47.5 wt% AIN47.5wt% SiC with 5 wt % $\alpha$-SiC at 203$0^{\circ}C$ for 1 h, th complete solid solutions with a single phase of 2H could be obtained. The appreciable amount of $\alpha$-SiC could develop the columnar inter-grains of 4H phase and the stable 2H phase with the relatively uniform composition and grain size distributions. The effect of $\alpha$-SiC on the phases present and compositional microstructures with columnar inter-grains was invetigated using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The fracture toughness and Vickers hardness of the hot-pressed solid solutions wre examined by the indentation-fracture-test method.