• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.705-706
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• 2010

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
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• pp.102.1-102.1
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• 2000

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.95.2-95
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• 2003

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.281.2-281.2
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• 2016

Two-dimensional van der Waals (2D vdWs) materials have been extensively studied for future electronics and materials sciences due to their unique properties. Among them, black phosphorous (BP) has shown infinite potential for various device applications because of its high mobility and direct narrow band gap (~0.3 eV). In this work, we demonstrate a few-nm thick BP-based nonvolatile memory devices with an well-known poly(vinylidenefluoride-trifluoroethylene) [P(VDF-TrFE)] ferroelectric polymer gate insulator. Our BP ferroelectric memory devices show the highest linear mobility value of $1159cm^2/Vs$ with a $10^3$ on/off current ratio in our knowledge. Moreover, we successfully fabricate the ferroelectric complementary metal-oxide-semiconductor (CMOS) memory inverter circuits, combined with an n-type $MoS_2$ nanosheet transistor. Our memory CMOS inverter circuits show clear memory properties with a high output voltage memory efficiency of 95%. We thus conclude that the results of our ferroelectric memory devices exhibit promising perspectives for the future of 2D nanoelectronics and material science. More and advanced details will be discussed in the meeting.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.298.1-298.1
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• 2016

Two-dimensional materials have been received significant interest after the discovery of graphene due to their fascinating electronic and optical properties for the application of novel devices. However, graphene lack of certain bandgap which is essential requirement to achieve high performance field-effect transistors. Analogous to graphene materials, molybdenum disulfide ($MoS_2$) as one of transition-metal dichalcogenides family presents considerable bandgap and exhibits promising physical, chemical, optical and mechanical properties. Here we studied nonvolatile memory based on $MoS_2$ which is grown by chemical vapor deposition (CVD) method. $MoS_2$ growth was taken on $1.5{\times}1.5cm^2$ $SiO_2$/Si-substrate. The samples were analyzed by Raman spectroscopy, atomic force microscopy and X-ray photoelectron spectroscopy. Current-voltage (I-V) characteristic was carried out HP4156A. The CVD-$MoS_2$ was analyzed as few layers and 2H-$MoS_2$ structure. From I-V measurement for two metal contacts on CVD-$MoS_2$ sample, we found typical resistive switching memory effect. The device structures and the origin of nonvolatile memory effect will be discussed.

• 한국식품조리과학회지
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• 제16권2호
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• pp.173-181
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• 2000

To understand the influences of NaCl concentration and fermentation temperature on the ripening process of low salt fermented squids, squid with 5%, 7% and 9% salt were fermented at 10$\^{C}$ and 20$\^{C}$. The result of the changes of volatile basic nitrogen and free amino acids during the fermentation of squids are as follows. As a result of the observations on the changes of physicochemical components during the fermentation process of the low-salted squids, all the pH, VBN and NH$_2$-N were increased and therefore the fermentation was promoted. Considering the changes of net components according to the fermentation, ATP (Adenosine triphosphate) and ADP (Adenosine diphosphate) lost and could not be detected among the nucleotides and their related compounds. Besides, AMP (Adenosine monophosphate) existed only in the initial stage and inosine, hypoxanthine were the main components of nucleotides and their related compounds. Nonvolatile organic acids are mainly lactic acid, acetic acid and also they occupied more than 80%. Seeing the composition of free amino acid, the major amino acids are proline, arginine, methionine, alanine and glutamic acid.

• 한국식품조리과학회지
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• 제9권4호
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• pp.257-260
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• 1993

조미료로서 된장의 수용도를 높일 수 있는 자료를 제공하고자 황곡균으로 개량식 된장을 제조하고 이것을 180일 간 숙성시키면서 맛성분으로 중요한 역할을 하는 유리당, 휘발성 유기산, 비휘발성 유기산을 분석하였다. 그 결과 된장의 감미원인 유리당은 glucose>xylose> arabinose순서로 많이 존재하였다. 휘발성 유기산은 ace-tic, formic, butyric, propionic acid가 검출되었고 총량은 숙성 60일가지 증가하였다. 180일 숙성 후, 휘발성유기 산의 함량은 acetic>propioniclbutyric>formic acid순서 로 많이 존재하였다. 비휘발성 유기산은 담금 직후부터 succinic>glutaric>lactir acid순서로 많았으며 숙성 45일부터 tartaric>citric>malic이 뒤를 이은 순서로 생성되었다.

• International Journal of Internet, Broadcasting and Communication
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• 제10권4호
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• pp.6-11
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• 2018

As embedded memory technology evolves, the traditional Static Random Access Memory (SRAM) technology has reached the end of development. For deepening the manufacturing process technology, the next generation memory technology is highly required because of the exponentially increasing leakage current of SRAM. Non-volatile memories such as STT-MRAM (Spin Torque Transfer Magnetic Random Access Memory), PCM (Phase Change Memory) are good candidates for replacing SRAM technology in embedded memory systems. They have many advanced characteristics in the perspective of power consumption, leakage power, size (density) and latency. Nonetheless, nonvolatile memories have two major problems that hinder their use it the next-generation memory. First, the lifetime of the nonvolatile memory cell is limited by the number of write operations. Next, the write operation consumes more latency and power than the same size of the read operation.These disadvantages can be solved using the compiler. The disadvantage of non-volatile memory is in write operations. Therefore, when the compiler decides the layout of the data, it is solved by optimizing the write operation to allocate a lot of data to the SRAM. This study provides insights into how these compiler and architectural designs can be developed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.305-309
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• 2002

We have successfully fabricated a Metal-Ferroelectric-Insulator-Semiconductor (MFIS) structure using Bi$\sub$4-x/La$\sub$x/Ti$_3$O$\sub$12/ (BLT) ferroelectric thin film and SiO$_2$/Nitride/SiO$_2$ (ONO) stacked buffer layers for single transistor type ferroelectric nonvolatile memory applications. BLT films were deposited on 15 nm-thick ONO buffer layer by sol-gel spin-coating. The dielectric constant and the leakage current density of prepared ONO film were measured to be 5.6 and 1.0 x 10$\^$-8/ A/$\textrm{cm}^2$ at 2MV/cm, respectively, It was interesting to note that the crystallographic orientations of BLT thin films were strongly effected by pre-bake temperatures. X-ray diffraction patterns showed that (117) crystallites were mainly detected in the BLT film if pre-baked below 400$^{\circ}C$. Whereas, for the films pre-baked above 500$^{\circ}C$, the crystallites with preferred c-axis orientation were mainly detected. From the C-V measurement of the MFIS capacitor with c-axis oriented BLT films, the memory window of 0.6 V was obtained at a voltage sweep of ${\pm}$8 V, which evidently reflects the ferroelectric memory effect of a BLT/ONO/Si structure.

• 한국연초학회지
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• 제14권2호
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• pp.151-158
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• 1992

Field experiment was conducted to investigate the effects of stalk position, compound fertilizer application rate (N-P2O5-K2O : 10-10-20 : 75, 100, 125kg/03), paddy and upland soil and varieties, NC82 &KF103, on nonvolatile organic and higher fatty acids of flue-cured tobacco. Followed by stalk position, malic, citric, malonic and succinic acid contents were significantly increased with higher stalk position, but oleic and linoleic acid contents were decreased with higher stalk position. The higher application rate of compound fertilizer results in increasing citric, malic, malonic and succinic acid contents, but the contents of higher fatty acids were not significantly influenced by fertilizer application rate. The cured leaf cultivated in paddy soil was higher citric and malic acid contents than in upland soil, but the contents of higher fatty acids have no difference between paddy and upland soil. The variety of KF103 was higher citric and linoleic acid contents than that of NC82, but the contents of higher fatty acids have no difference between varieties.