• Journal of IKEEE
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• v.22 no.3
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• pp.565-569
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• 2018

For the conventional power MOSFET (metal-oxide semiconductor field-effect transistor) device structure, there exists a tradeoff relationship between specific on-state resistance (Ron,sp) and breakdown voltage (BV). In order to overcome this tradeoff, a super-junction (SJ) trench MOSFET (TMOSFET) structure with uniform or non-uniform doping concentration, which decreases linearly in the vertical direction from the N drift region at the bottom to the channel at the top, for an optimal design is suggested in this paper. The on-state resistance of $0.96m{\Omega}-cm2$ at the SJ TMOSFET is much less than that at the conventional power MOSFET under the same breakdown voltage of 100V. A design methodology for the edge termination is proposed to achieve the same breakdown voltage and on-state resistance as the main body of the super-junction TMOSFET by using of the SILVACO TCAD 2D device simulator, Atlas.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.63-64
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• 2009

The TFTs have been fabricated with 3 different geometry SID electrodes which have the same channel W/L ratio (W/L = 5) due to constant channel resistance, The 3 samples have different channel widths (350, 150, and $25\;{\mu}m$) and channel lengths (70, 30, and $5\;{\mu}m$) by fixed channel W/L ratio simultaneously on one chip for reliable comparisons. Resultant on-current and field effect mobility are proportional to the channel width, while the subthreshold swing is inversely proportional to the channel width mainly due to the change of contact resistance. These results show that the contact resistance strongly affects the device performances and should be considered in the applications.

• 전기의세계
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• v.30 no.10
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• pp.639-644
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• 1981

PVC is a kind of electric insulation polymer. But we get some deteriorations in electrical characteristics of the PVC, when it is used on the radioactive field. In order to find out the cause of the deterioration, we investigate the surface-resistance, volume-resistance, dielectric constant and dielectric loss angle of the soft and hard PVC which is irradiated by the Co$^{60}$ .gamma. radioactivity. From the experiment, we can conclude the followings 1. Radio-activity proof characteristic in the soft PVC is stronger than in the hard PVC. 2. The resistance of PVC which is irradiated by the radio-activity decrease exponentially. 3. The dielectric constant and the dielectric loss angle of PVC irradiated by Co$^{60}$ .gamma.ray reach maximum value in first few time.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.445-452
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• 2012

This study is used to analyze the distribution of resistance factors and the relationships of flow resistance with the field measurements which consist of the total 2,604 rivers for 1,865 bed material in natural channels and 739 vegetation in vegetated channels. Resistance factor relationships and distribution range of Manning roughness coefficients and Darcy-Weisbach friction coefficients by the regression analysis are derived from the power law form as a function of flow discharge and friction slope with bed materials and vegetations in natural and vegetated rivers, respectively.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.2
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• pp.125-130
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• 2001

This paper presents an indirect field-oriented (IFO) induction motor position servo drives which uses the model following adaptive controller with the artificial neural network(ANN)-based rotor resistance estimator. The model reference adaptive system(MRAS)-based 2-layer ANN estimates the rotor resistance on-line and a linear model-following position controller is designed by using the estimated the rotor resistance value. At the end, a fuzzy logic system(FLS) is added to make the position controller robust to the external disturbances and the parameter variations. The simulation results show the effectiveness of the proposed method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.9
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• pp.747-750
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• 2009

The TFTs have been fabricated with 3 different geometry SID electrodes which have the same channel W/L ratio (W/L = 5) due to constant channel resistance, The 3 samples have different channel widths (350, 150, and 25 ${\mu}m$) and channel lengths (70, 30, and 5 ${\mu}m$) by fixed channel W/L ratio simultaneously on one chip for reliable comparisons. Resultant on-current and field effect mobility are proportional to the channel width, while the subthreshold swing is inversely proportional to the channel width mainly due to the change of contact resistance. These results show that the contact resistance strongly affects the device performances and should be considered in the applications.

• ETRI Journal
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• v.37 no.5
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• pp.951-960
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• 2015

For a conventional power metal-oxide-semiconductor field-effect transistor (MOSFET), there is a trade-off between specific on-state resistance and breakdown voltage. To overcome this trade-off, a super-junction trench MOSFET (TMOSFET) structure is suggested; within this structure, the ability to sense the temperature distribution of the TMOSFET is very important since heat is generated in the junction area, thus affecting its reliability. Generally, there are two types of temperature-sensing structures-diode and resistive. In this paper, a diode-type temperature-sensing structure for a TMOSFET is designed for a brushless direct current motor with on-resistance of $96m{\Omega}{\cdot}mm^2$. The temperature distribution for an ultra-low on-resistance power MOSFET has been analyzed for various bonding schemes. The multi-bonding and stripe bonding cases show a maximum temperature that is lower than that for the single-bonding case. It is shown that the metal resistance at the source area is non-negligible and should therefore be considered depending on the application for current driving capability.

• Asian Journal of Turfgrass Science
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• v.18 no.4
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• pp.211-219
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• 2004

Transgenic zoysiagrass (Zoysia japonica cv. Zenith) plants have been obtained by particle bombardment of embryogenic callus with the plasmid pSMABuba, which contains hygromycin resistance (hpt) and bialaphos resistance (bar) genes. Parameters on DNA delivery efficiency of the particle bombardment were partially optimized using transient expression assay of a chimeric $\beta-glucuronidase$(gusA) gene driven by the CaMV 35S promoter. Stably transfarmed zoysiagrass plants were recovered with a selection scheme using hygromycin. Transgenic zoysiagrass plants were confirmed by PCR analysis with specific primer for bar gene. Expression of the transgene in transformed zoysiagrass plants was demonstrated by Reverse transcriptase (RT)-PCR analysis. All the tested transgenic plants showed herbicide BastaR resistance at the field application rate of $0.1\%-0.3\%$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.2
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• pp.170-176
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• 2000

The joints with multi-interfaces was expected to have low DC resistance compared with those with single interface. The small size joint specimens joined with Nb3Sn sub-cables were fabricated to investi-gate the DC performance in the range of 0 to 600A transport current without external magnetic field. The joints with multi-interfaces have a few n-Ohm resistance, which is much lower than that of single lap joint. Because the interfaces between sub-cables of multi-interfaced joint are more complicated than those of single-interfaced joint, the soldering condition between sub-cables is very effective on the joint DC resistance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.10
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• pp.794-798
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• 2011

This paper was carried out design of 1,700 V Base Resistance Thyristor for fabrication. We decided conventional BRT (base resistance thyristor) device and Trench Gate type one for design. we carried out device and process simulation with T-CAD tools. and then, we have extracted optimal device and process parameters for fabrication. we have analysis electrical characteristics after simulations. As results, we obtained 2,000 V breakdown voltage and 3.0 V Vce,sat. At the same time, we carried out field ring simulation for obtaining high voltage.