• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 D
• /
• pp.1947-1949
• /
• 1999

Carrier lifetime in silicon power devices caused switching delay and excessive power loss at high frequency switching. We studied transient turn-on/turn-off transient characteristics of electron irradiated and proton irradiated silicon pn junction diodes. Both the electron and proton irradiation of power devices have already become a widely used practice to reduce minority carrier lifetime locally[1]. The sample is n+p junction diode, made by ion implantation on a $20\Omega.cm$ p-type wafer. We investigated turn-on/turn-off transient & breakdown voltage characteristics by digital oscilloscope. Our data show that proton irradiated samples show better performance than electron irradiated samples.

• 전기전자학회논문지
• /
• 제24권2호
• /
• pp.598-603
• /
• 2020

본 논문에서는 Push-Pull 패스 트랜지스터 구조로 인하여 향상된 Load Transient 특성을 향상시킨 LDO(Low Drop-Out)를 제안하였다. LDO 레귤레이터 내부의 오차증폭기의 출력단과 패스 트랜지스터의 게이트단 사이에 제안된 Push-Pull 회로와 출력단에 Push-Pull 회로를 추가하여 전압 라인에 들어오는 Overshoot, Undershoot를 개선시켜 기존의 LDO 레귤레이터보다 개선된 Load Transient 특성의 델타 피크 전압 값을 갖는다. 제안하는 회로는 Cadence의 Virtuoso, Spectre 시뮬레이션을 이용하여 삼성 0.13um 공정에서 특성을 분석하였다.

• Journal of Semiconductor Engineering
• /
• 제1권1호
• /
• pp.46-56
• /
• 2020

This article highlights new opportunities of inorganic semiconductor materials for bio-implantable electronics, as a subset of 'transient' technology defined by an ability to physically dissolve, chemically degrade, or disintegrate in a controlled manner. Concepts of foundational materials for this area of technology with historical background start with the dissolution chemistry and reaction kinetics associated with hydrolysis of nanoscale silicon surface as a function of temperature and pH level. The following section covers biocompatibility of silicon, including related other semiconductor materials. Recent transient demonstrations of components and device levels for bioresorbable implantation enable the future direction of the transient electronics, as temporary implanters and other medical devices that provide important diagnosis and precisely personalized therapies. A final section outlines recent bioresorbable applications for sensing various biophysical parameters, monitoring electrophysiological activities, and delivering therapeutic signals in a programmed manner.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2000년도 하계학술대회 논문집
• /
• pp.930-933
• /
• 2000

To understand the behavior of electron, ions and radicals on radio-frequency non-equilibrium plasma, it is necessary to know the basic information about its fundamental properties and reactions. Especially, the transient response of radio-frequency plasma has an important means of controlling selective etch rates and investigating the stability of a plasma chemical process. In this paper, we present the results of periodic steady-state behavior and transient behavior carbon Tetrafluoride(CF$_4$) discharge at 0.2 Torr in a 2 cm gap parallel-plate. After the number densities of charged particles became steady-state, the applied voltage was increased or decreased in an instant and the transient behavior of charged particles and radicals was investigated from one steady-state to the next steady state.

• 세라미스트
• /
• 제21권1호
• /
• pp.44-54
• /
• 2018

Oxide semiconductor has been spotlighted as a channel material of TFTs in AMLCD as an alternative to Si, due to high mobility ( > $5cm^2/Vs$). It is also one of the strong candidates for TFTs in AMOLED because of high bias stability at amorphous phase. Beyond the advantages mentioned above, oxide semiconductor has many strengths such as transparency, low fabrication temperature and relatively low fabrication cost. For those reasons, the application of oxide semiconductor is not limited to display but can be extended to new types of electronics, for example, transient electronics for human implantable devices. From this context, oxide materials that have been used as semiconductor and insulator at transient electronics are investigated respectively, and conductor and substrate candidates are also explained, since transient electronics require systematic consideration beyond individual oxide films.

• 전기전자학회논문지
• /
• 제23권2호
• /
• pp.552-556
• /
• 2019

본 논문에서는 전류 제어 회로를 이용하여 load Transient response 특성을 향상시킨 capless LDO(low drop-out) 레귤레이터를 제안하였다. LDO 레귤레이터 내부의 오차증폭기와 패스 트랜지스터 사이에 전류 조절 회로를 두어 전압 라인에 들어오는 전류특성을 개선시켜 기존의 LDO 레귤레이터보다 향상된 transient 응답특성을 갖는다. 제안된 회로는 cadence의 virtuoso, spectre 시뮬레이터를 이용하여 0.18 um 공정에서 특성을 분석하였다. 실험 결과에 따르면, 제안된 회로 구성을 이용한 LDO의 load transient response는 기존 LDO과 비교하여 부하 전류가 rising time인 경우 1.954 us에서 1.378 us, falling time인 경우 19.48 us에서 13.33 us으로 약 29%, 28% 개선된 응답속도를 가진다.

• ETRI Journal
• /
• 제41권6호
• /
• pp.820-828
• /
• 2019

A highly reliable conductive adhesive obtained by transient liquid-phase sintering (TLPS) technologies is studied for use in high-power device packaging. TLPS involves the low-temperature reaction of a low-melting metal or alloy with a high-melting metal or alloy to form a reacted metal matrix. For a TLPS material (consisting of Ag-coated Cu, a Sn96.5-Ag3.0-Cu0.5 solder, and a volatile fluxing resin) used herein, the melting temperature of the metal matrix exceeds the bonding temperature. After bonding of the TLPS material, a unique melting peak of TLPS is observed at 356 ℃, consistent with the transient behavior of Ag₃Sn + Cu₆Sn₅ → liquid + Cu₃Sn reported by the National Institute of Standards and Technology. The TLPS material shows superior thermal conductivity as compared with other commercially available Ag pastes under the same specimen preparation conditions. In conclusion, the TLPS material can be a promising candidate for a highly reliable conductive adhesive in power device packaging because remelting of the SAC305 solder, which is widely used in conventional power modules, is not observed.

• 대한전기학회논문지:전력기술부문A
• /
• 제51권6호
• /
• pp.296-301
• /
• 2002

Modern power systems are very complex and to model them completely is impractical for electromagnetic transient studies. Therefore areas outside the immediate area of interest must be represented by some form of Frequency Dependent Network Equivalent (FDNE). In this paper a method for developing Frequency Dependent AC system Equivalent (FDACSE) using Z-domain rational Function Fitting is presented and demonstrated. The FDACSE is generated by Linearized Least Squares Fitting(LSF) of the frequency response of a Z-domain formulation. This 1 & 2 port FDACSE have been applied to the New Zealand South Island AC power system. The electromagnetic transient package PSCAD/EMTDC is used to assess the transient response of the 1 & 2 port FDACSE developed under different condition (linear load, fault and nonlinear loading). The study results have indicated the robustness and accuracy of 1 & 2 port FDACSE for electromagnetic transient studies.

• ETRI Journal
• /
• 제42권5호
• /
• pp.790-798
• /
• 2020

Herein, a low-ripple coarse-fine digital low-dropout regulator (D-LDO) without ringing in the transient state is proposed. Conventional D-LDO suffers from a ringing problem when settling the output voltage at a large load transition, which increases the settling time. The proposed D-LDO removes the ringing and reduces the settling time using an auxiliary power stage which adjusts its output current to a load current in the transient state. It also achieves a low output ripple voltage using a comparator with a complete comparison signal. The proposed D-LDO was fabricated using a 65-nm CMOS process with an area of 0.0056 μ㎡. The undershoot and overshoot were 47 mV and 23 mV, respectively, when the load current was changed from 10 mA to 100 mA within an edge time of 20 ns. The settling time decreased from 2.1 ㎲ to 130 ns and the ripple voltage was 3 mV with a quiescent current of 75 ㎂.

• Journal of Power Electronics
• /
• 제16권2호
• /
• pp.584-597
• /
• 2016

This paper focuses on an improvement in the transient performance of Boost converters when the load changes abruptly. This is achieved on the basis of the nature trajectory in Boost converters. Three key aspects of the transient performance are analyzed including the storage energy change law in the inductors and capacitors of converters during the transient process, the ideal minimum voltage deviation in the transient process, and the minimum voltage deviation control trajectory. The changing relationship curve between the voltage deviation and the recovery time is depicted through analysis and simulations when the load suddenly increases. In addition, the relationship curve between the current fluctuation and the recovery time is obtained when the load suddenly decreases. Considering the aspects of an increasing and decreasing load, this paper proposes the transient performance synthetic optimized trajectory and control laws. Through simulation and experimental results, the transient performances are compared with the other typical three control methods, and the ability of proposed synthetic trajectory and control law to achieve optimal transient performance is verified.