MOS에서 低溫氣相成長法에 의한 酸化膜의 溫度 依存性

崔世崑,魚秀海 영남대학교 공업기술연구소 1985 연구보고 Vol.13 No.2

This paper investigates the effects of temperature on electrical properties of metal oxide semiconductor by the method of low temperature chemical vapor deposition. The experimental study indicates that electrical capacitance is mainly varied by surface-state charge for the thickness of 810A under low temperature, and its temperature dependence is increased with the greater thickness of the oxidized layer.

배관 로봇을 이용한 배관 검사 자동화 기술

노세곤,최혁렬 한국비파괴검사학회 2002 한국비파괴검사학회지 Vol.22 No.3

현재까지 검사를 목적으로 하는 배관 검사용 로봇에 관한 많은 연구가 소개되어 왔다. 그러나 지하매설 배관의 복잡한 배관 요소 내에서 주행 할 수 있는 충분한 이동성을 갖추고 있는 로봇을 개발한다는 것은 여전히 어려운 것처럼 보인다. 배관 검사에 사용하기 위한 로봇은 수평관 및 수직관과 같은 기본적인 배관요소 내에서 자유롭게 주행해야 한다. 더불어 축소관이나 곡관에서 주행 할 수 있고 특히 분기관에서 조항 능력은 필수적이다. 본 논문에서는 배관 검사 로봇의 개발에 있어 필수적인 요소와 기술이 소개되며 지난 수년간 연구를 통하여 개발한 배관검사 로봇이 소개된다. Up to now a wide variety of researches on inpipe robots for inspection have been introduced, but it still seems to be difficult to construct a robot providing mobility sufficient to navigate inside the complicated configuration of underground pipelines. The robot for the inspection of pipelines should freely move along the basic configuration of pipelines such as along horizontal or vertical pipeline. Moreover it should be able to travel along reducers and elbows. and especially the capability for steering in branches is essential to it. In this report, critical pointss and technologies in the development of the inpipe inspection robots are introduced and inpipe robots developed for last several years are introduced.

치아 수복용 불소함유 glass filler의 제조 및 특성

김대성,최세영,김경남,김광만,김중곤 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.3

The purpose of this study was the reaching test of restorative glass according to composition. Mixtures of SrF₂, CaF₂and SiO₂were fused in platinum crucible. The glasses were ground and fraction which passed through a 400 mesh (38㎛) sieve were collected. The powder specimens were analyzed by a DTA and XRD. Then powder specimen were inserted to D. I. water with various of dissolution time and composition at 37℃. Fluoride ion, cation release, solubility, and pH change were estimated. It was clear that the glasses were formed except S0.65. In S0.40, Tg, Ts, and Tc were 630, 672, and 813℃ respectively. In initial 0.5 hrs., amounts of released fluoride ion and cation were about 90% of total released amounts and released rate was decreased with dissolution time. Amount of released fluoride ion and cation were increased with decreasing SiO₂ in glass filler. And released rate was decreased rapidly by adding CaF₂. This was caused by structural variation in glass filler. Solubility was similar tendency with ion released. The pH of D.I. water was 4.5. But in intial 0.5 hrs., pH was 8.2∼9.8., and decreased according to dissolution time. This is caused by ionic changing with cation and H* ion.

熱刺戟 電流法에 依한 MOS酸化層內 移動性 陽이온의 擧動에 關한 考察

金種聲,崔世崑,姜星模 嶺南大學校 工業技術硏究所 1988 연구보고 Vol.16 No.1

TSIC(Thermally stimulated ionic current) method, based on the repeated measurements with various heating rates, has been used to investigate the kinetic behavior of mobile ions in the SiO₂layers of an Al-SiO₂-Si system. Experimental results have shown two current peaks at the temperature ranges of 80℃-120℃(A peak) and 400℃-450℃(B peak) respectively, which are caused by the release of Na+ ions and K+ ions trapped at the Al-SiO₂ interface and the Si-SiO₂ interface respectively, in a MOS structure. From the results, activation energies (E), attempt-to-escape frequencies (S) and the initial number of trapped ions(n。)are evaluated for each group by the various heating rate method. According to the values of E.S and n。, it is found that deeper traps are distributed in the Si-SiO₂ interface and that K+ions are trapped in deeper trap than Na+ ions. It is also found that the magnitude of the current peaks is increased while the tempratures showing those peaks are decreased, as the gate voltage is increased.

8개 압저항 브릿지구조를 이용한 저 타축 감도 실리콘 가속도센서

徐熙敦,李榮泰,崔世崑 경북대학교 센서기술연구소 1995 센서技術學術大會論文集 Vol.6 No.1

A low off-axis sensitivity piezoresistive accelerometer has been presented. The off-axis sensitivity was reduced by arrangement of eight piezoresistors on two the beams. The structure and stress distribution of the accelerometer was optimized using FEM(finite element modeling) simulation. The dependence of sensitivity and resonance frequency were also simulated as a function of the beam length for a constant overall size(2000μm). Accurate thickness control of the beams was realized by the etch-stop techonology using SDB(silicon direct bonding) wafer SiO_(2) layer and RIE(reative ion etching) method. This method is relatively simple and very useful for fabrication of accelerometer.

整流方式에 따른 醫療用 X-線 裝置의 特性

김재문,권덕문,최세곤 嶺南大學校 工業技術硏究所 1995 工業技術硏究所論文集 Vol.23 No.2

The output characteristics on various rectification methods of X-ray equipments for the purpose of medical use are investigated by means of X-ray multimeter. in comparison the measured values with setting values, the accuracy of X-ray tube voltage and illumination time was varied in the range of +70% in case of three phase type including inverter type. The inverter type also showed a good reproducibility. As the experimental results, it is desirable that the inverter type X-ray equipment will be widely used in the near future.

高精度의 DUAL-SLOPE 積分型 A/D 變換器 設計

박차훈,서희돈,최세곤 嶺南大學校 工業技術硏究所 1990 연구보고 Vol.18 No.1

In this paper, an effective method, which eliminates the error of the preamplifier, the integrator and the comparator, is proposed. An improved dual-slope integrating A/D converter, composed of the two-stage operational amplifier which is controlled by the control logic circuit switches and the variable ring counter, is for high accuracy. The results of computer simulation show that the conversion error is eliminated completely and the accuracy improved up to the level of the amplification of operational amplifier. These results satisfy the requirment of performance for the high accuracy dual-slope integrating A/D converter.

Al/P-Si MIS型 太陽電池의 製作과 그 特性에 관한 硏究

金載文,安永奉,崔世崑 嶺南大學校 工業技術硏究所 1985 연구보고 Vol.13 No.1

The Al/P-Si MIS solar cells were fabricated by vacuum evaporation method. The interfacial oxide layer was grown by ramp heating for 5 minutes. Thin Aluminum film was deposited on the chemically etched (100) surface of a single sillcon crystal by vacuum evaporation. The solar cells showed good rectification properties which have the built-in potential of 0.76V and the quality factor of 1.6 under dark condition. The cells indicated that the open circuit voltage, short circuit photocurrent density, fill factor and energy conversion efficiency were 0.53V, 35mA/㎠, 0.62 and 12.4%, respectively, under 98mw/㎠ tungsten halogen lamp irradiation.

생체신호처리용 ASIC 칩 개발

배용욱,박차훈,서희돈,최세곤 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

The biotelemetry system transmits monitored physiological signal from multiple subjects to an electrical instrument at remote place where this information can be observed via electrical or optical link. In this paper, we developed an optical linked telemetry system which can transmit 6-channel physiological signals from 4 subjects, simultaneously. The proposed telemetry system is fabricated with Altera FPGA chip(EPM7128LC84-20) and 0.8μm CMOS n-well process technology. We designed a All-Digital PLL to synchronize with the external measurement system which consisted of a command signal transmitter and a telemetry signal demodulator. The operation characteristic of a All-Digital PLL is superior than an enforced synchronization oscillator which consisted of negative elements and a comparator. The required time to synchronize with a external measurement system at the maximum phase error is about 10.3ms. The novel external measurement system is implemented with Altera FPGA chip (EFM7096LC84-15).

고감도 에어백용 실리콘 가속도센서의 설계

손미정,김경기,서희돈,최세곤 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.1

This paper presents the high sensitivity silicon piezoresitive accelerometer for possible use in an automotive airbag system. Two basic types of silicon piezoresitive accelerometers(bridge-type and cantilever-type)have some problems in the sensitivity and resonance frequency. The bridge-type has high resonance frequency and low sensitivity, but the cantilever-type has everse property. in order to improve the properties of the silicon piezoresistive accelerometer, we propose a new type of silicon accelerometer that have three beams. The proposed structure is that two beams are located at the each comer of the right side, and the other is at center of the left side. The optimized overallsize of the new type accelerometer is more smaller than two basic types of accelerometer. In the simulated reselts using analytical formelae and finite-element modeling(FEM), It's maximum stress is 26MPa and resonance frequency is 3250Hz for 50 G acceleration, respectively. The proposed structure is expected to be applied to much wider use automotive airbag application than the other structures.