• 한국전기전자재료학회논문지
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• 제21권4호
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• pp.300-304
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• 2008

A novel characterization method was investigated to estimate the trap generation during the program /erase cycles in nand flash memory cell. Utilizing Fowler-Nordheim tunneling current, floating gate potential and oxide electric field, we established a quantitative model which allows the knowledge of threshold voltage (Vth) as a function of either program or erase operation time. Based on our model, the derived results proved that interface trap density (Nit) term is only included in the program operation equation, while both Nit and oxide trap density (Not) term are included in the erase operation equation. The effectiveness of our model was tested using 50 nm nand flash memory cell with floating gate type. Nit and Not were extracted through the analysis of Program/Erase speed with respect to the endurance cycle. Trap generation and cycle numbers showed the power dependency. Finally, with the measurement of the experiment concerning the variation of cell Vth with respect to program/erase cycles, we obtained the novel quantitative model which shows similar results of relationship between experimental values and extracted ones.

• 전자공학회논문지A
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• 제29A권8호
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• pp.71-77
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• 1992

According to increasing the doping concentration in p-n junction, a tunneling current through trap as well as SRH(Shockley-Read-Hall) generation-recombination current in depletion region occurs. It is the tunneling current that is a dominant current at the forward bias. In this paper, the new tunneling-recombination equation is derived. The thermal generation-recombination current and tunneling current though trap can be easily calculated at the same time because this equation has the same form as the SRH generation-recombination equation. For the validity of this equation, 2 kind of samples are simulated. The one is $n^{+}$-p junction device fabricated with MCT(Mercury Cadmium Telluride, mole fraction=0.29), the other Si n$^{+}-p^{+}$ junction. From the results for MCT $n^{+}$-p junction device and comparing the simulated and expermental I-V characteristics for Si n$^{+}-p^{+}$ junction, it is shown that this equation is a good description for tunneling through trap and thermal generation-recombination current calculation.

• 한국응용곤충학회지
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• 제43권1호
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• pp.49-54
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• 2004

고추의 주요 해충인 담배나방은 유충이 과실 속에서 가해하기 때문에 방제가 어려운 해충이다. 수원지역의 고추 포장에서 페로몬 트랩을 이용하여 성충의 발생소장을 조사한 결과 전체 발생기간은 5월 하순부터 10월 상순까지였으며 각 세대의 발생 최성기는 6월 하순, 7월 하순 8월 상순, 8월 하순 9월 상순이었다. 월동세대와 1세대 성충 발생기간 중에 트랩유인 수준은 그 이후에 발생하는 유충에 의한 과실의 피해정도를 잘 반영하였다. 그러나 고추 생육후기에 발생하는 2세대의 경우 트랩에 유인되는 성충의 수는 매우 많았으나 유충에 의한 피해율은 그다지 높지 않았다. 페로몬 트랩으로 조사된 세대별 성충 발생시기에 관한 정보를 토대로 약제방제 시험을 수행한 결과, 각 세대별 성충 발생 최성기를 중심으로 연 5회에 걸쳐 살충제를 살포하면 유충에 의한 과실 피해를 효과적으로 줄일 수 있는 것으로 조사되었다.

• International Journal of Oral Biology
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• 제30권2호
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• pp.47-57
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• 2005

Leptin, the product of the obese gene, is a circulating hormone secreted primarily from adipocytes. Several results suggest that leptin is important mediators of bone metabolism. The present study was undertaken to determine the effects of leptin on anti-osteoclastogenesis using murine precursors cultured on Ca-P coated plates and on the production of osteoprotegerin (OPG) in osteoblastic cells. Additionally, this study examined the possible involvement of prostaglandin $E_2\;(PGE_2)$/protein kinase C (PKC)-mediated signals on the effect of leptin on anti-osteoclastogenesis to various culture systems of osteoclast precursors. Osteoclast generation was determined by counting tartrate-resistant acid phosphatase positive [TRAP (+)] multinucleated cells (MNCs). Osteoclastic activity was determined by measuring area of resorption pits formed by osteoclasts on Ca-P coated plate. The number of 1,25-dihydroxycholecalciferol $(1,25[OH]_2D_3)$- or $PGE_2$-induced TRAP (+) MNCs in the mouse bone marrow cell culture decreased significantly after treatment with leptin. The number of receptor activator of NF-kB ligand (RANKL)-induced TRAP (+) MNCs in M-CSF dependent bone marrow macrophage (MDBM) cell or RAW264.7 cell culture decreased significantly with leptin treatment. Indomethacin inhibited osteoclast generation induced by $1,25[OH]_2D_3$ and dexamethasone, however, no significant differences were found in the leptin treated group when compared to the corresponding indomethacin group. Phorbol 12-myristate 13-acetate (PMA), a PKC activator, inhibited osteoclast generation induced by $1,25[OH]_2D_3$. The number of TRAP (+) MNCs decreased significantly with treatment by PMA at concentrations of 0.01 and $0.1{\mu}M$ in culture. Leptin inhibited PMA-mediated osteoclast generation. Isoquinoline-5-sulfonic 2-methyl-1-piperazide dihydrochloride (H7) had no effect on osteoclast generation induced by $1,25[OH]_2D_3$. Cell culture treatment with leptin resulted in no significant differences in osteoclast generation compared to the corresponding H7 group. Indomethacin showed no significant effect on TRAP (+) MNCs formation from the RAW264.7 cell line. PMA inhibited TRAP (+) MNCs formation induced by RANKL in the RAW264.7 cell culture. H7 had no effect on osteoclast generation from the RAW264.7 cell line. There was no difference compared with the corresponding control group after treatment with leptin. $1,25[OH]_2D_3$- or $PGE_2$-induced osteoclastic activity decreased significantly with leptin treatment at a concentration of 100 ng/ml in mouse bone marrow cell culture. Indomethacin, PMA, and H7 significantly inhibited osteoclastic activity induced by $1,25[OH]_2D_3$ in mouse bone marrow cell culture. No significant differences were found between the leptin treated group and the corresponding control group. The secretion of OPG, a substance known to inhibit osteoclast formation, was detected from the osteoblasts. Treatment by leptin resulted in significant increases in OPG secretion by osteoblastic cells. Taken these results, leptin may be an important regulatory cytokines within the bone marrow microenvironment.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.461-464
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• 1999

This study has been investigated that traps generated inside of the oxide and at the oxide interfaces by the stress bias voltage. The traps are charged near the cathode with negative charge and charged near the anode with positive charge. The charge state of the traps can easily be changed by application of low voltages after the stress high voltage. These trap generation involve either electron impact ionization processes or high field generation processes. It determined to the relative traps locations inside the oxides ranges from 113.4$\AA$ to 814$\AA$ with capacitor areas of 10$^{-3}$ $\textrm{cm}^2$ . The oxide charge state of traps generated by the stress high voltage contain either a positive or a negative charge.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권5호
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• pp.2084-2100
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• 2020

Operating system (OS) kernel function call graphs have been widely used in OS analysis and defense. However, most existing methods and tools for generating function call graphs are designed for application programs, and cannot be used for generating OS kernel function call graphs. This paper proposes a virtualization-based call graph generation method called Acquire in Trap (AIT). When target kernel functions are called, AIT dynamically initiates a system trap with the help of a virtualization technique. It then analyzes and records the calling relationships for trap handling by traversing the kernel stacks and the code space. Our experimental results show that the proposed method is feasible for both Linux and Windows OSs, including 32 and 64-bit versions, with high recall and precision rates. AIT is independent of the source code, compiler and OS kernel architecture, and is a universal method for generating OS kernel function call graphs.

• JSTS:Journal of Semiconductor Technology and Science
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• 제12권3호
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• pp.360-369
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• 2012

The causes of showing different subthreshold slopes (SS) in programmed and erased states for two different charge trap flash (CTF) memory devices, SONOS type flash memory with gate-all-around (GAA) structure and TANOS type NAND flash memory with planar structure were investigated. To analyze the difference in SSs, TCAD simulation and low-frequency noise (LFN) measurement were fulfilled. The device simulation was performed to compare SSs considering the gate electric field effect to the channel and to check the localized trapped charge distribution effect in nitride layer while the comparison of noise power spectrum was carried out to inspect the generation of interface traps ($N_{IT}$). When each cell in the measured two memory devices is erased, the normalized LFN power is increased by one order of magnitude, which is attributed to the generation of $N_{IT}$ originated by the movement of hydrogen species ($h^*$) from the interface. As a result, the SS is degraded for the GAA SONOS memory device when erased where the $N_{IT}$ generation is a prominent factor. However, the TANOS memory cell is relatively immune to the SS degradation effect induced by the generated $N_{IT}$.

• 대한전자공학회논문지SD
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• 제41권8호
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• pp.1-8
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• 2004

두께가 3nm인 게이트 산화막을 사용한 n-MOSFET에 정전압 스트레스를 가하였을 때 관찰되는 SILC 및 soft breakdown 열화 및 이러한 열화가 소자 특성에 미치는 영향에 대해 실험하였다. 열화 현상은 인가되는 게이트 전압의 극성에 따라 그 특성이 다르게 나타났다. 게이트 전압이 (-)일 때 열화는 계면 및 산화막내 전하 결함에 의해 발생되었지만, 게이트 전압이 (＋)일 때는 열화는 주로 계면 결함에 의해 발생되었다. 또한 이러한 결함의 생성은 Si-H 결합의 파괴에 의해 발생할 수 있다는 것을 중수소 열처리 및 추가 수소 열처리 실험으로부터 발견하였다. OFF 전류 및 여러 가지 MOSFET의 전기적 특성의 변화는 관찰된 결함 전하(charge-trapping)의 생성과 직접적인 관련이 있다. 그러므로 실험 결과들로부터 게이트 산화막으로 터널링되는 전자나 정공에 의한 Si 및 O의 결합 파괴가 게이트 산화막 열화의 원인이 된다고 판단된다. 이러한 물리적 해석은 기존의 Anode-Hole Injection 모델과 Hydrogen-Released 모델의 내용을 모두 포함하게 된다.

• 한국전기전자재료학회논문지
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• 제18권11호
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• pp.996-1000
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• 2005

Experimental results are presented for the degradation of 3 nm-thick gate oxide $(SiO_2)$ under both Negative-bias Temperature Instability (NBTI) and Hot-carrier-induced (HCI) stresses using P and NMOSFETS, The devices are annealed with hydrogen or deuterium gas at high-pressure $(1\~5\;atm.)$ to introduce higher concentration in the gate oxide. Both interface trap and oxide bulk trap are found to dominate the reliability of gate oxide during electrical stress. The degradation mechanism depends on the condition of electrical stress that could change the location of damage area in the gate oxide. It was found the trap generation in the gate oxide film is mainly related to the breakage of Si-H bonds in the interface or the bulk area. We suggest that deuterium bonds in $SiO_2$ film are effective in suppressing the generation of traps related to the energetic hot carriers.

• Journal of Nutrition and Health
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• 제34권4호
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• pp.401-408
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• 2001

The spontaneous frequency of genetic damage and the possible relationship of this damage to total radical-trapping antioxidant potential(TRAP) and antioxidant vitamins, including plasma levels of $\alpha$-carotene, $\beta$-carotene, cryptoxanthin, retinol, $\alpha$-tocopherol and ${\gamma}$-tocopherol in humans were investigated in 57 subjects using two indices of genetic damage, SCE & HFC frequency. The mean of SCE and HFC frequencies were weakly correlated with plasma TRAP(r=-0.305, p<0.1 for SCEs: r=-0.297, p<0.1 for HFCs, respectively), but those were strongly negatively correlated with plasma $\beta$-carotence(r=-0.385, p<0.01 for SCEs : r=-0.392, p<0.01 for HFCs) and cryptoxanthin(r=-0.312, p<0.05 for SCEs : r=0.335, p<0.05 for HFCs, respectively) levels in the subjects. However, those DNA damage markers including SCE and HFC did not correlate with either plasma $\alpha$-carotene, $\alpha$-tocopherol or retinol concentrations. The mean of SCE and HFC frequencies were positively correlated with plasma ${\gamma}$-tocopherol level(r=0.421, p<0.01 for SCEs : r=0.399, p<0.01 for HFCs, respectively). These findings indicate that increased cytogenetic DNA changes, as determined by SCE and HFC frequencies are possibly associated with generation of free radicals in lymphocytes and decreased plasma antioxidant vitamin($\beta$-carotene and cryptoxanthin) status in the subjects. (Korean J Nutrition 34(4) : 401~08, 2001)