• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.8
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• pp.799-805
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• 2004

Two dimensional MEDICI simulator is used to study the characteristics of latch-up current of Dual Gate Emitter Switched Thyristor. The simulation is done in terms of the current-voltage characteristics, latch-up current density, ON-voltage drop and electrical property with the variations of p-base impurity concentrations. Compared with the other power devices such as MOS Controlled Cascade Thyristor(MCCT), Conventional Emitter Switched Thyristor(C-EST) and Dual Channel Emitter Switched Thyristor(DC-EST), Dual Gate Emitter Switched Thyristor(DG-EST) shows to have the better electrical characteristics, which is the high latch-up current density and low forward voltage-drop. The proposed DG-EST which has a non-planer p-base structure under the floating $N^+$ emitter indicates to have the better characteristics of latch-up current and breakover voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.234-234
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• 2010

Most high efficiency silicon solar cells use a passivated selective emitter. It have been an important research subject for crystalline silicon solar cells for decades. It is being used in production for high efficiency solar cells. Most of the selective emitter process require expensive extra masking, etching steps, and a double diffusion process making selective emitters not cost effective. In this paper, we study method for single diffusion step selective emitter process as an alternative to not cost effective double diffusion process. Cost effective selective emitter that the efficiency should be increased significantly (mare than 0.2%) and that the process should simple, robust and cheap.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.5
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• pp.585-589
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• 2009

In this paper, passive direction-finding localization of the emitter using noisy line-of-bearing (LOB) measurements is considered. The performance of the LOB-based emitter localization using linear LSE algorithm is given. The Dependence of the performance on bias of emitter location and sensor trajectory is illustrated using the numerical results.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.449.2-449.2
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• 2014

태양전지용 III-V족 화합물 반도체 물질인 GaAs는 1.42eV의 Energy Band-gap (Eg)을 가지고 있기 때문에 이론적으로 단일접합 태양전지로는 가장 높은 수준의 광-전 변환효율 달성이 가능하다. 비록 emitter의 조건 가변으로 설정을 했음에도 불구하고, 처음 기본적인 구조였던 emiier 두께 75 nm, 도핑농도 상에서 효율이 24.53%가 될 정도로 큰 효율이 나오게 되었다. TCAD simulation을 이용하여 emitter의 도핑농도와 두께를 가변하여 가장 높은 효율이 나오는 emitter 조건을 찾는 실험을 진행하였다. 시뮬레이션 결과 emitter두께 100 nm에서 도핑농도가 인 경우에 Voc=28.43, Jsc=25.84, Jph=29.12, FF=87.76%, 효율은 25.84%가 나오는 것을 확인 수 있었다.

• Applied Microscopy
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• v.46 no.3
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• pp.155-159
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• 2016

This paper analyses the relationship between the distribution of a dielectric layer on the apex of a metal field electron emitter and the distribution of electron emission. Emitters were prepared by coating a tungsten emitter with a layer of epoxylite resin. A high-resolution scanning electron microscope was used to monitor the emitter profile and measure the coating thickness. Field electron microscope studies of the emission current distribution from these composite emitters (Tungsten-Clark Electromedical Instruments Epoxylite resin [Tungsten/CEI-resin emitter]) have been carried out. Two forms of image have been observed: bright single-spot images, thought to be associated with a smooth substrate and a uniform dielectric layer; and multi-spot images, though to be associated with irregularity in the substrate or the dielectric layer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.11
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• pp.1023-1028
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• 2003

The field emission characteristics are studied by simulation for carbon nanotube triode structures with a strip-shaped emitter and a gate hole aligned with it. Two structures, one with double-edge and the other with single edge are analyzed. They show good emission characteristics. Emissions of electrons are concentrated on the edges of emitter and the emitted current increases as the distance between emitter and gate decreases. For single-edged emitter, the emitted electrons form a narow strip-shaped beam which has a good directionality. These triode structures have advantages in that they can be easily fabricated and aligned for assembly.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1413-1415
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• 1994

A novel magnetotransistor using a separated drift field with the guard ring around the emitter has been designed and fabricated. The operating principle of the proposed magnetic field sensor is based on the emitter injection modulation. The $p^+$ guard ring around the n-type emitter confines drifted electrons in the emitter, hence the induced Hall voltage in the emitter is increased. The measured relative sensitivity of the separated drift magnetotransistor with the guard ring is about 100 times larger than that without the guard ring.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.9
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• pp.523-526
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• 2000

A dual gate trench emitter IGBT structure is proposed and studied numerically using the device simulator MEDICI. The on-state forward voltage drop latch-up current density turn-off time and breakdown voltage of the proposed structure are compared with those of the conventional DMOS-IGBT and trench gate IGBT structures. The proposed structure forms an additional channel and increases collector current level resulting in reduction of on -state forward voltage drop. In addition the trench emitter increases latch-up current density by 148% in comparison with that for the conventional DMOS-IGBT and by 83% compared with that for the trench gate IGBT without degradation in breakdown voltage when the half trench gate width(Tgw) and trench emitter depth(Ted) are fixed at $1.5\mum\; and\; 2\mum$, respectively

• Current Optics and Photonics
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• v.3 no.5
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• pp.445-450
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• 2019

The influence of high-power laser diode (HPLD) emitter width on the device performance is investigated for 975-nm (In,Ga)(As,P)/(Al,Ga)As broad-area HPLDs, using self-consistent electro-thermal-optical simulation. To guarantee the simulation's accuracy, simulated results are matched with the measured results for a sample HPLD with fitting parameters. The influences of HPLD emitter width on temperature distribution, output power, and the beam product parameter (BPP) are analyzed for three different emitter widths of 50, 70, and $90{\mu}m$. It is found that a device with smaller emitter width exhibits both thermal rollover and thermal blooming at lower output power, but smaller BPP.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.53.1-53.1
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• 2010

결정질 실리콘 태양전지의 효율을 향상시키기 위하여 수광면에 서로 다른 도핑농도를 가지는 고농도 도핑영역과 저농도 도핑영역으로 이루어진 emitter를 형성하는 것이 요구되며 이를 selective emitter라 칭한다. Selective emitter를 형성하면 고농도 도핑영역에서 금속전극과 저항 접촉이 잘 형성되기 때문에 직렬 저항이 최소화되고 저농도 도핑영역에서는 전하 재결합의 감소로 인하여 태양전지의 변환효율이 상승하는 이점이 있다. Selective emitter의 형성방법은 이미 다양한 방법이 제안되고 있으나, 본 연구에서는 기존에 제시된 방법과는 다르게 열산화 시 dopant redistribution에 의한 Boron depletion 현상을 이용하여 selective emitter를 형성하는 방법을 제안하였고, 이를 Simulation을 통하여 검증하였다. 초기 emitter 확산 후 junction depth는 0.478um, 면저항은 $104.2{\Omega}/sq.$ 이었으며, nitride masking layer 두께는 0.3um로 설정하였다. $1100^{\circ}C$에서 30분간 습식산화 공정을 거친 후 nitride mask가 있는 부분의 junction depth는 1.48um, 면저항은 $89.1{\Omega}/sq$의 값을 보였고, 산화막이 형성된 부분의 junction depth는 1.16um, 면저항은 $261.8{\Omega}/sq$의 값을 보였다. 위 조건의 구조를 가진 태양전지의 변환 효율은 19.28%의 값을 나타내었고 Voc, Jsc 및 fill factor는 각각 645.08mV, $36.26mA/cm^2$, 82.42%의 값을 보였다. 한편 일반적인 구조로 설정한 태양전지의 변환 효율, Voc, Isc 및 fill factor는 각각 18.73%, 644.86mV, $36.26mA/cm^2$, 80.09%의 값을 보였다.