• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.257-260
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• 1990

Monte Carlo simulations of electron impact ionization in silicon utilizing simple spherical band approximation including L valley are presented. The mean energy of electron at high electric field is lowered and the threshold energy of electron impact ionizaiotn is smeared out to $E_x$ by including L valley. This work also presents the importance of the modeling of L valley by calculating the electron population rate of it over the threshold energy of eletron impact ionization, which is higher than 10%

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1213-1218
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• 2004

The present article reports extensive numerical results on the non-local characteristics of ultra-short pulsed laser-induced breakdowns of fused silica ($SiO_{2}$) by using the multivariate Fokker-Planck equation. The nonlocal type of multivariate Fokker-Planck equation is modeled on the basis of the Boltzmann transport formalism to describe the ultra-short pulsed laser-induced damage phenomena in the energy-position space, together with avalanche ionization, three-body recombination, and multiphoton ionization. Effects of electron avalanche, recombination, and multiphoton ionization on the electronic transport are examined. From the results, it is observed that the recombination becomes prominent and contributes to reduce substantially the rate of increase in electron number density when the electron density exceeds a certain threshold. With very intense laser irradiation, a strong absorption of laser energy takes place and an initially transparent solid is converted to a metallic state, well known as laser-induced breakdown. It is also found that full ionization is provided at intensities above threshold, all further laser energy is deposited within a thin skin depth.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.473-478
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• 2003

3-Amino-2-hydroxy-4(3H)-quinazolinone (3) was prepared via condensation of 1 with hydrazine hydrate. Treatment of 3 with appropriate acid in $POCl_3$, ethyl chloroacetate and activated olefinic compounds in DMF yielded the corresponding 3-(substituted)amino-2-hydroxy-4(3H)-quinazolinones 4, 5 and 6. The electron impact ionization mass spectra of compounds 3 and 4 show a weak molecular ion peak and a base peak of m/z 146 resulting from a cleavage fragmentation. The compounds 5 and 6 give a characteristic fragmentation pattern with a very stable fragment of benzopyrazolone (m/z 132).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.96-99
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• 2012

We fabricated fully depleted (FD) SOI-based 1T-DRAM cells with planar channel or recessed channel and the electrical characteristics were investigated. In particular, the dependence of memory operating mode on the channel structure of 1T-DRAM cells was evaluated. As a result, the gate induced drain leakage current (GIDL) mode showed a better memory property for planar type 1T-DRAM. On the other hand, the impact ionization (II) mode is more effective for recessed type.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.480-484
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• 2000

The channel length influence of n-channel Si-based FETs is investigated by computer simulation. Using a two-dimensional hydrodynamic model, devices having various gate length are examined. We have observed the characteristics of LDD model of MOSFET by investigating of their current, voltage, electric field and impact ionization. These devices are scaled using various factors. We have analyzed I-V characteristics and the effect of impact ionization according to channel length.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.3
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• pp.201-207
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• 2002

In this paper, we haute proposed a novel trench electrode Base Resistance Thyristor(BRT) and trench electrode BRT with a intrinsic region. New power BRTs have shown superior electrical characteristics including the snab-back effect and the forward blocking voltage more than the conventional BRT. Especially, the trench electrode BRT with the intrinsic region has obtained high blocking voltage of 1600V. The blocking voltage of conventional BRT is about 400V at the same size. Because the breakdown mechanism of the BRT is the avalanch breakdown by impact ionization, the trench electrode BRT with intrinsic region has suppressed impact ionization, effectively. If we use this principle, we can develop a super high voltage power device and it applies to another power device including IGBT, EST and etc.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1038-1041
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• 2002

In this paper, we have proposed a novel trench electrode Base Resistance Thyristor(BRT) and trench electrode BRT with a intrinsic region. A new power BRTs have shown superior electrical characteristics including snab-back effect and forward blocking voltage more than the conventional BRT Especially, the trench electrode BRT with intrinsic region has obtained high blocking voltage of 1600V. The blocking voltage of conventional BRT is about 400V at the same size. Because the breakdown mechanism of BRT is avalanch breakdown by impact ionization, the trench electrode BRT with intrinsic region has suppressed impact ionization, effectively. If we use this principle, we can develope super high voltage power device and applicate to another power device including IGBT, EST and etc,

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.243-246
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• 2001

In this paper, we have proposed a novel trench electrode Base Resistance Thyristor(BRT) and trench electrode BRT with a intrinsic region. A new power BRTs have shown superior electrical characteristics including snab-back effict and forward blocking voltage more than the conventional BRT. Especially, the trench electrode BRT with intrinsic region has obtained high blocking voltage of 1600V. The blocking voltage of conventional BRT is about 400V at the same size. Because the breakdown mechanism of BRT is avalanch breakdown by impact ionization, the trench electrode BRT with intrinsic region has suppressed impact ionization, effectively. If we use this principle, we can develope super high voltage power devices and applicate to another power devices including IGBT, EST and etc.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.293-293
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• 2005

The differences between floating and grounded body effects in polycrystalline silicon thin-film transistors (polysilicon TFTs) are investigated by making a body contact. The floating body effects such as kink effect, subthreshold slope change, and body current characteristics are explained and modeled by impact ionization, which causes source body turn on, and activates the parasitic bipolar junction transistors (BJTs). These effects become crucial for channel lengths of 4㎛ or shorter. Our data show that making a body contact reduces kink effects significantly and identifies impact ionization mechanism in polysilicon TFTs.

• Journal of Integrative Natural Science
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• v.4 no.2
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• pp.99-102
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• 2011

Effect of protonation and deprotonation of ionization compounds is an important application in Comparative molecular field analysis (CoMFA). There are enough information's were reported about different CoMFA applications such as Series design and selection of training set, Geometries and optimizations of molecules, Effect of partial atomic charges, bioactive conformations and alignment, Interaction energy fields, Effects of different grid spacing etc. However limited information's are available about the ionization of compounds. This study aimed at the critical review of about the effects of protonation of ionizable molecules and its impact on the predictability of CoMFA models. We also discussed about previous implications and the things needed to be considered to come for a final conclusion about its impact on CoMFA predictability.