• 대한기계학회논문집B
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• 제24권10호
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• pp.1359-1367
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• 2000

In-situ particle monitors(ISPMs) are widely used for monitoring contaminant particles in vacuum-based semiconductor manufacturing equipment. In the present research, the performance of a Particle Measuring Systems(PMS) Vaculaz-2 ISPM at low pressures has been studied. We generated the uniform sized methylene blue particle beams using three identical aerodynamic lenses in the center of the vacuum line, and measured the detection efficiency of the ISPM. The effects of particle size, particle concentration, mass flow rate, system pressure, and arrangement of aerodynamic lenses on the detection efficiency of the ISPM were examined. Results show that the detection efficiency of the ISPM greatly depends on the mass flow rate, and the particle Stokes number. We also found that the optimum Stokes number ranges from 0.4 to 1.9 for the experimental conditions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.437-441
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• 1995

In this paper, the ultra precision positioning system for servo motor and piezo actuator using dual servo loop control has been developed. For positioning system having long distance with ultra precision, the combination of global stage and micro stage is required. Servo moter and ball screw are used as a master stage and piezo acuator as a fine stage. By using this system, an positional precision witin .+-. 30nm has been achieved at dual servo loop control. When using micro stage, an positional precision within .+-. 10nm has been achieved. This result can be applied to develop semiconductor equipment such as wafer stepper.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.177-177
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• 2009

• 대한의용생체공학회:의공학회지
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• 제15권1호
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• pp.1-8
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• 1994

Electrofusion of cabbage protoplasts was performed with a developed equipment which consists of a parallel wire electrode, a AC field generator, and a pulse generator. Exposure of protoplasts to an alternating current field of 450 KHz causes attraction to each other which leads to chains of protoplasts extending from the electrode. Intra-specific protoplast fusion was effectively induced within the pearl chains by the additional application of a single high-intensity DC square wave pulse of 1 KV/cm for 1-3 msec. To improve the performance, micro fusion electrode fabricated from the semiconductor technology and microcontroller based field an, d pulse generator was proposed. The viability of protoplasts after an application of electric field at optimum condition was reduced by only 5 % compared with that of pre-application. A prototype of fusion electrode, which consists of insulator-structure, was successfully fabricated by using photosensitive polyimide.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.357-359
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• 2004

Fuse is the initial equipment of Protective Relay The installation standard of Fuse has been used for long time in Power Facilities. However according to the innovative development of Electric & Electronic element(=semiconductor) Technology, Protective Relay and other Power Equipments are being changed into Digitalization and Multi-Functional Convergence. In contrast with it, the installation standard of Fuse is just the same. There is a need to give careful consideration to it. This study will bear a Part of producing a safe and efficient Power by examining the current installation of primal 8f secondary 1'use in multi-functional PT of Power plant, giving a problem careful consideration and suggesting suitable countermeasures.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.259-261
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• 2002

Recently, according to the spread of semiconductor applied technology like motor speed control contrivance, power conversion installation and so on, harmonic ingredients occurred in switching operation flow into a distribution system and increase voltage distortion of distribution system and bring on obstacles like damage, lowering of capability, false operation and so on of various electrical installation. So, in order to consider a countermeasure to limit occurrence quantity of harmonic source, harmonic interception and others, precision measurement and analysis on voltage, current, power, power factor, the each ingredient of harmonic order, the percentage of total harmonic distortion and so forth are needed. In this paper monitoring system to measure and analyze power quality connected with power harmonics was developed and it's performance is verified by measuring and analyzing three-phase voltage and current of R, S, T in the three-phase and four-wire system using the developed measurement system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.616-619
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• 2004

Lightning surge damages of low voltage equipments in building are increasing due to increase in electrical and communication networks in the information-oriented society. And electronic equipments contained electrical circuits with semiconductor are very weak against lightning surge. The surge protective devices for electronic circuit in electronic equipments and AC power lines are becoming more widely. To achieve effective method of surge protection, there are needs for correlation between lightning surge protective effect of electronic equipment and installation method of surge protective device. This paper describes as a result of experiments for correlation between lightning surge protective effect and installation method of surge protective device.

• International Journal of Fluid Machinery and Systems
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• 제1권1호
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• pp.92-100
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• 2008

The main objective of this study was to clarify the origin of the unsteady flows arising in a mixed-flow vaneless diffuser system and also the effects of physical components of the system. The testing equipment consists of a straight tube, a swirl generator, and a mixed-flow vaneless diffuser. Pressure fluctuations of the flow through the tube and diffuser were measured by using a semiconductor-type pressure transducer and analyzed by an FFT analyzer. In the experiment, the velocity ratio (axial velocity/peripheral velocity) of the internal flow, and the geometric parameters of the diffuser were varied. Two kinds of unsteady flows were measured according to the combination of the components, and the origin of each unsteady flow was clarified. The fundamental frequencies of unsteady flows arose were examined by two-dimensional small perturbation analysis.

• 대한기계학회논문집A
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• 제26권9호
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• pp.1727-1735
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• 2002

The usage of beam scanning type laser marker is rapidly increasing in the field of semiconductor equipment. A device called ″beam adjuster″ is employed to adjust the visible diode laser, which points the marking position for various setting. The device is very sensitive to manufacturing tolerance and assembly condition. Axiomatic approach has been applied to the design of the device. An existing design is analyzed based on the Independence Axiom. The existing design is found to violate the axiom. Two new designs are proposed to satisfy the Independence Axiom. The Information Axiom is utilized to evaluate the designs. A design is selected to have the minimum information content. The significance of this research is that a full cycle of axiomatic design is applied to a real engineering product.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.311-314
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• 1997

According to the development of industrial equipment such as semiconductor manufacturing machines, optical device, and precision machine tool, a high-precision translation system with wide range has been required. This paper describes a high-precision 2-axis translation system, which consists of microstage and global stage. In order to achieve the highresolution in the long range, some engineering techniques are used. Three linear guides with flexible coupling are adopted to reduce the motor vibration in the global stage. A simple elastic hinge structure activated by five PZT is applied to reduce the angular dev~atlon. As the result of combination of microstage and global stage associated with some engineering techniques, the 2-axis translation system can measure the 200 X 200 mrn range with the nanometer accuracy.