• 대한전기학회논문지
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• 제38권12호
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• pp.1041-1047
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• 1989

In recent years, a.c servomotors have been gradually replacing d.c servomotors in various high-performance applications such as machine tools and industrial robots. Inparticular, the high performance slip-frequency control of an induction motor, which is often called the vector control, is considered ane of th ebest a.c drives. In this paper, the transient state equations and vector control algorithms of an induction type servomotor are described mathematically by using the two- axis theory (d-q coordinates). According to the result of these algorithms, we scheme the speed control system for the motor in which the vector control is adopted to give high performance. Motor drive through a PWM inverter with power MOSFET is controlled so that the actual input current to the motor may track the current reference obtained from a micro-computer (8086 CPU). Driving experiments are performed in the range of 0 to 3000 rpm, and it is verified that high speed response is obtained for this system.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권3호
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• pp.252-258
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• 2013

In this paper, a thermally stable nickel silicide technology using the co-sputtering of nickel and titanium atoms capped with TiN layer is proposed for nano-scale metal oxide semiconductor field effect transistor (MOSFET) applications. The effects of the incorporation of titanium ingredient in the co-sputtered Ni layer are characterized as a function of Ti sputtering power. The difference between the one-step rapid thermal process (RTP) and two-step RTP for the silicidation process has also been studied. It is shown that a certain proportion of titanium incorporation with two-step RTP has the best thermal stability for this structure.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.903-906
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• 1999

고 농도의 반송자가 존재하는 영역에서의 지배적인 산란 효과인 억셉터 및 도너 산란과 반송자-반송자 산란, Screening 효과를 수치적으로 구현하는 방법을 제안한다. 또한 높은 바이어스가 인가된 경우 Slotboom 변수를 사용함으로써 발생하는 부동 소숫점 한계를 극복하기 위한 척도변환 방법을 제안한다. 구현된 모델의 정확성을 검증하기 위해서 자체 개발된 소자 시뮬레이터인 BANDIS를 이용하여, 척도변환에 대해서 n-MOSFET 소자로 17〔V〕이상에서도 모의실험이 가능함을 보였고, 전력 BJT 소자에 대해서 Philips Unified 이동도 모델의 모의 실험 결과, 상업용 2차원 소자 시뮬레이터인 MEDICI에 비해 척도변환은 최대 12%, Philips Unified 이동도는 최대 2.8%이내의 상대오차를 보였다

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.918-921
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• 1999

The breakdown voltage in fully depleted SOI N-MOSFET’s have been studied over a wide range of film thicknesses, channel doping, and channel lengths. An asynmmetric Source/Drain SOI technology is proposed, which having the advantages of Normal LDD SOI(Silicon-On-Insulator) for breakdown voltage and gives a high drivability of LDD SOI without sacrificings hot carrier immunity The two-dimensional simulations have been used to investigate the breakdown behavior in these device. It is found that the breakdown voltage(BVds) is almost same with high current drivability as that in Normal LDD SOI device structure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.74-76
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• 2005

수평형 에미터 스위치트 사이리스터(Lateral Emitter Switched Thyristor, LEST)의 고전압 전류 포화 특성을 위한 새로운 보호회로가 제안하였으며 성공적으로 제작 및 측정하였다. LEST의 부유(浮遊, floating) n+ 전압이 보호 MOSFET의 문턱 전압 보다 커지면 보호 회로는 LEST의 동작 모드를 regenerative 상태에서 non-regerative 상태로 전환시킨다. 일반적인 LEST의 전압 전류 포화 특성이 17 V로 제한되는 것에 비해 제안된 회로와 결합된 LEST는 200V 이상의 고전압 전류 포화 특성을 보였으며, Hard Switching Fault(HSF) 단락 회로 상황에서도 $10{\mu}s$ 이상 견디는 단락 회로 유지 능력을 보였다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제8권3호
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• pp.221-226
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• 2008

A new two dimensional (2-D) analytical model for the Threshold Voltage on dual material surrounding gate (DMSG) MOSFETs is presented in this paper. The parabolic approximation technique is used to solve the 2-D Poisson equation with suitable boundary conditions. The simple and accurate analytical expression for the threshold voltage and sub-threshold swing is derived. It is seen that short channel effects (SCEs) in this structure is suppressed because of the perceivable step in the surface potential which screens the drain potential. We demonstrate that the proposed model exhibits significantly reduced SCEs, thus make it a more reliable device configuration for high speed wireless communication than the conventional single material surrounding gate (SMSG) MOSFETs.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 추계학술대회
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• pp.160-161
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• 2019

본 논문에서는 Si-MOSFET 및 GaN-HEMT 기반 All Metal Induction Cooktop의 고효율 동작을 위한 공진네트워크 설계 및 운전주파수영역을 제시한다. 이를 위해 워킹 코일과 용기의 등가 파라미터를 바탕으로 동작 주파수에 따른 공진 네트워크를 각각 설계한다. 또한 시뮬레이션 및 수학적 계산을 통해 설계된 시스템의 주파수 조건 별 손실 비교를 통해 각 스위칭 소자에 따른 적합한 공진네트워크 설계방안을 제시한다.

• 대한전기학회논문지
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• 제41권6호
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• pp.579-587
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• 1992

This paper is to study on the step-up DC-DC converter for power system which yields output characteristics of low voltage and high current, such as fuel cell generation system. DC-AC-DC scheme is suggested for high ratio of voltage conversion. Three phase MOSFET-SPWM inverter is adopted for intermediate AC conversion and inverter output frequency is chosen at 400[Hz] in order to reduce the size of magnetic circuit and DC filter. Since control strategy which combines voltage controller with current controller in parallel is used, good output performance is obtained both in steady state and in transient state like load variation, not only in single unit operation but also in parallel operation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.806-808
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• 1993

New soft recovery drive which can alleviate the loss due to reverse recovery of diode is proposed. By using this drive, the reverse current of the diode is minimized and stabilized because there is inner local feedback loop between the turn-on current of the power MOSFET and the reverse recovery current of the diode. The loss and EMI noise can be considerably reduced in this way. Brief operational principle and experimental results are included to verify the usefulness.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.704-706
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• 1993

This paper, introduces a Current-fed type High-Frequency Inverter with self turning devices. By replacing Thyrisors used for power source of heat treatment with high speed switching element, MOSFET in current type Inverter, the proposed Inverter makes high speed performance with several 100kHz. This paper also depicts some operating principles of the proposed circuits and general operating characteristics. Steady state solution on state variables in analysis of the proposed circuit is described generally by using normalized parameter and its characteristics depending on separate ratio(n) is also shown.