• Journal of Microbiology and Biotechnology
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• 제20권1호
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• pp.54-62
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• 2010

A novel harpin-like protein, HpaXm, was described from cotton leaf blight bacteria, Xanthomonas citri subsp. malvacearum. The hpaXm was found to be localized between hrp2 and hrcC. A phylogenetic analysis of the complete amino acid sequence or solely the 13 highly conserved residues $H_2N$-SEKQLDQLLTQLI-COOH in the N-terminal $\alpha$-helix indicates that HpaXm is evolutionarily closer to HpaGXag and HpaXac than to Hpa1Xoo and Hpa1Xoc. A synthesized peptide containing two heptads, 39-LDQLLTQLIMALLQ-52, from the N-terminal a-helical region of HpaXm displayed comparable activity in inducing a hypersensitive response, but two other synthesized derivatives, $HpaXm{\Delta}T44C$ and $HpaXm{\Delta}M48Q$, showed reduced HR-triggering activity. The data from a GST trap test revealed that HpaXm was released into the extracellular medium, hpaXm mutant deficient for the leader peptide (1-MNSLNTQIGANSSFL-15) was unable to be secreted outside cells but still induced HR in tobacco leaves.

• 한국전기전자재료학회논문지
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• 제20권7호
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• pp.569-574
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• 2007

In this paper, the reliability (NBTI degradation: ${\Delta}V_{th}$) and device characteristic of nano-scale PMOSFET with plasma nitrided oxide (PNO) is characterized in depth by comparing those with thermally nitrided oxide (TNO). PNO case shows the reduction of gate leakage current and interface state density compared to TNO with no change of the $I_{D.sat}\;vs.\;I_{OFF}$ characteristics. Gate oxide capacitance (Cox) of PNO is larger than TNO and it increases as the N concentration increases in PNO. PNO also shows the improvement of NBTI characteristics because the nitrogen peak layer is located near the $Poly/SiO_2$ interface. However, if the nitrogen concentration in PNO oxide increases, threshold voltage degradation $({\Delta}V_{th})$ becomes more degraded by NBT stress due to the enhanced generation of the fixed oxide charges.

• 한국전기전자재료학회논문지
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• 제24권3호
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• pp.182-187
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• 2011

In this paper, PBTI characteristics of NMOSFETs with La incorporated HfSiON and HfON are compared in detail. The charge trapping model shows that threshold voltage shift (${\Delta}V_{\mathrm{T}}$) of NMOSFETs with HfLaON is greater than that of HfLaSiON. PBTI lifetime of HfLaSiON is also greater than that of HfLaON by about 2~3 orders of magnitude. Therefore, high charge trapping rate of HfLaON can be explained by higher trap density than HfLaSiON. The different de-trapping behavior under recovery stress can be explained by the stable energy for U-trap model, which is related to trap energy level at zero electric field in high-k dielectric. The trap energy level of two devices at zero electric field, which is extracted using Frenkel-poole emission model, is 1,658 eV for HfLaSiON and 1,730 eV for HfLaON, respectively. Moreover, the optical phonon energy of HfLaON extracted from the thermally activated gate current is greater than that of HfLaSiON.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• 제21권1호
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• pp.31-46
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• 1993

대기 가열율과 복사속의 연직 분포를 계산하기 위하여 two-stream/delta-Eddington 근사법을 이용한 복사전달모형이 개발되었다. 이 모형의 결과를 ICRCCM의 결과와 비교하므로써 모형의 완성도를 평가하였다. 이 모형은 정확성 뿐 아니라 경제적인 면에서도 태양복사를 계산하는데 적합한 것으로 증명되었다. 대기 꼭대기에서의 복사속과 지표에서의 복사속 간의 관계를 비교하므로써 자외선 B 영역(UV-B; 280-320nm)의 특징들이 검토되었다. 이 영역에서는 강한 오존 흡수가 있어 UV-B의 관계가 2차 함수로 나타난다. 또한, 성층권 오존 감소와 화산 폭발로 기인한 성층권 에어로졸 안개가 UV-B 복사에 미치는 영향을 다양한 태양의 천정각에서 조사했다. 태양의 천정각이 증가함에 따라 지표 UV-B도 증가하였다. 성층권 에어로졸은 후방 산란을 통해 행성 반사도를 증가시켰다. 행성 반사도는 에어로졸 효과로 인해 태양의 천정각이 증가함에 따라 증가한다. 그러나, 행성 반사도의 변화가 태양의 천정각 변화에 따라 민감하게 나타나지는 않는다. 이것은 태양의 천정각이 클 때 에어로졸의 산란 효과가 상대적으로 긴 복사 경로에서 포화되었기 때문일 것이다. 끝으로, 화산 폭발에서 비롯된 성층권 에어로졸이 지표 UV-B 복사 강도에 미치는 지역적 영향이 추정되었다. 고위도에서는 에어로졸의 광자 포획(photon trap)이나 일몰 효과로 복사 강도가 증가하는 반면 저위도에서는 감소한다. 고위도에서 에어로졸의 산란과 오존 흡수는 지표 UV-B 복사의 최대 증가는 봄 기간 중에 양 반구 모두 중위도에서 나타난다.

• 한국응용곤충학회지
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• 제56권2호
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• pp.165-169
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• 2017

경남과 전남지역의 단감원에서 밤알락명나방의 발생소장과 성페로몬샘의 성분별 및 트랩 종류별 유인력을 조사하였다. 2014년부터 2016년까지 발생소장을 조사한 결과, 밤알락명나방은 년 3회 발생하는 것으로 조사되었다. 각 세대 성충의 발생시기는 월동세대는 4월 상순-5월 하순, 제1세대는 6월 상순-7월 하순, 제2세대는 8월 상순-10월 중순이었다. 성페로몬샘 성분별 유인력은 (Z9,E12)-tetradeca-9,12-dien-1-ol (Z9, E12-14OH) 단독 루어가 (Z)-tetradec-9-en-1-ol (Z9-14OH) 단독 루어보다 유인력이 뛰어났으며, 두 물질을 9:1로 혼합한 루어와 차이가 없었다. 깔대기 트랩과 흰색 및 붉은색 트랩을 비교해 본 결과 트랩 종류 간에는 유인수의 차이가 없었다.

• 한국전기전자재료학회논문지
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• 제25권1호
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• pp.24-28
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• 2012

In this study, we fabricated an amorphous InGaZnO pseudo-MOS transistor (a-IGZO ${\Psi}$-MOSFET) with a stacked $Si_3N_4/SiO_2$ (NO) gate dielectric and evaluated reliability of the devices with various thicknesses of a $SiO_2$ buffer layer. The roles of a $SiO_2$ buffer layer are improving the interface states and preventing degradation caused by the injection of photo-created holes because of a small valance band offset of amorphous IGZO and $Si_3N_4$. Meanwhile, excellent electrical properties were obtained for a device with 10-nm-thick $SiO_2$ buffer layer of a NO stacked dielectric. The threshold voltage shift of a device, however, was drastically increased because of its thin $SiO_2$ buffer layer which highlighted bias and light-induced hole trapping into the $Si_3N_4$ layer. As a results, the pseudo-MOS transistor with a 20-nm-thick $SiO_2$ buffer layer exhibited improved electrical characteristics and device reliability; field effective mobility(${\mu}_{FE}$) of 12.3 $cm^2/V{\cdot}s$, subthreshold slope (SS) of 148 mV/dec, trap density ($N_t$) of $4.52{\times}1011\;cm^{-2}$, negative bias illumination stress (NBIS) ${\Delta}V_{th}$ of 1.23 V, and negative bias temperature illumination stress (NBTIS) ${\Delta}V_{th}$ of 2.06 V.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.14-14
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• 2009

In this study, we investigated the effects of Cr dopant on the bulk trap level and grain boundary characteristics of $Bi_2O_3$-based ZnO (ZB) using dielectric functions such as $Z^*$, $Y^*$, $M^*$, ${\varepsilon}^*$, and $tan{\delta}$. More than two bulk traps of $Zn_i$ and $V_o$ probably in different ionization states could be identified in ZBCr($ZnO-Bi_2O_3-Cr_2O_3$). The grain boundaries of ZBCr could be electrochemically divided into two types: sensitive to ambient oxygen and thus electrically active one and oxygen-insensitive and thus electrically inactive one.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.751-754
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• 2000

When charge-trap SONOS cells are used flash memory, the tunneling program/erase condition to minimize the generation of interface traps was investigated. SONOSFET NVSM cells were fabricated using 0.35$\mu\textrm{m}$ standard memory cell embedded logic process including the ONO cell process. based on retrograde twin-well, single-poly, single metal CMOS process. The thickness of ONO triple-dielectric for memory cell is tunnel oxide of 24${\AA}$, nitride of 74 ${\AA}$, blocking oxide of 25 ${\AA}$, respectively. The program mode(Vg: 7,8,9 V, Vs/Vd: -3 V, Vb: floating) and the erase mode(Vg: -4,-5,-6 V, Vs/Vd: floating, Vb: 3V) by modified Fowler-Nordheim(MFN) tunneling were used. The proposed programming condition for the flash memory of SONOSFET NVSM cells showed less degradation($\Delta$Vth, S, Gm) characteristics than channel MFN tunneling operation. Also the program inhibit conditions of unselected cell for separated source lines NOR-tyupe flash memory application were investigated. we demonstrated that the program disturb phenomenon did not occur at source/drain voltage of 1 V∼4 V and gate voltage of 0 V∼4.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.263-272
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• 2011

Highly luminescent and monodisperse InP quantum dots (QDs) were prepared by a non-organometallic approach in a non-coordinating solvent. Fatty acids with well-defined chain lengths as the ligand, a non coordinating solvent, and a thorough degassing process are all important factors for the formation of high quality InP QDs. By varying the molar concentration of indium to ligand, QDs of different size were prepared and their absorption and emission behaviors studied. By spin-coating a colloidal solution of InP QD onto a silicon wafer, InP QD thin films were obtained. The thickness of the thin films cured at 60 and $200^{\circ}C$ were nearly identical (approximately 860 nm), whereas at $300^{\circ}C$, the thickness of the thin film was found to be 760 nm. Different contrast regions (A, B, C) were observed in the TEM images, which were found to be unreacted precursors, InP QDs, and indium-rich phases, respectively, through EDX analysis. The optical properties of the thin films were measured at three different curing temperatures (60, 200, $300^{\circ}C$), which showed a blue shift with an increase in temperature. It was proposed that this blue shift may be due to a decrease in the core diameter of the InP QD by oxidation, as confirmed by the XPS studies. Oxidation also passivates the QD surface by reducing the amount of P dangling bonds, thereby increasing luminescence intensity. The dielectric properties of the thin films were also investigated by capacitance-voltage (C-V) measurements in a metal-insulator-semiconductor (MIS) device. At 60 and $300^{\circ}C$, negative flat band shifts (${\Delta}V_{fb}$) were observed, which were explained by the presence of P dangling bonds on the InP QD surface. At $300^{\circ}C$, clockwise hysteresis was observed due to trapping and detrapping of positive charges on the thin film, which was explained by proposing the existence of deep energy levels due to the indium-rich phases.

• 한국전기전자재료학회논문지
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• 제23권12호
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• pp.936-941
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• 2010

In this study, we have investigated the effects of Mn dopant on the bulk trap levels and grain boundary characteristics of $Bi_2O_3$-based ZnO (ZB) varistor using admittance spectroscopy and dielectric functions (such as $Z^*,\;Y^*,\;M^*,\;\varepsilon^*$, and $tan\delta$). Admittance spectra and dielectric functions show two bulk traps of $Zn_i^{..}$ (0.20 eV) and $V^{\bullet}_o$ (0.29~0.33 eV) in ZnO-$Bi_2O_3-Mn_3O_4$ (ZBM). The barrier of grain boundaries in ZBM could be electrochemically single type. However, its thermal stability was slightly disturbed by ambient oxygen because the apparent activation energy of grain boundaries was changed from 0.79 eV at lower temperature to 1.08 eV at higher temperature. The grain boundary capacitance $C_{gb}$ was decreased slightly with temperature as 1.3~1.8 nF but resistance $R_{gb}$ decreased exponentially. The relaxation time distribution can result from the heterogeneity of the barriers constituting the varistor. It is revealed that Mn dopant in ZB reduced the heterogeneity of the barrier in grain boundaries and stabilized the barrier against the ambient temperature.