• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.967-968
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• 2007

This report is the study for laser scanning. Scanning control of $CO_2$ laser, He-Ne laser, used for the treatment of body skin, has relatively low band about hundered Hz. It could be used as a substitiute for expensive galvanometer that is the established scan method, which operates the number of KHz movement by using step motor when it operates low speed. To increase the accuracy of step motor's the angle of rotation, We could materialize 100Hz low band by using open loop, closed loop method with microprocessor. This causes it to be stable even direction by attaching electric capacity sensor. Therefore, We could expect to reduce the cost by manufacturing low band scanner rather than costly feedback galvanometer.

• Journal of the Korean Vacuum Society
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• v.4 no.S1
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• pp.130-137
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• 1995

Deopsition of thermal quality SiO2 using a high density plasma ECR CVD process has been demonstrated to give void and seam free gap fill of high aspect ratio metallization structures with a simple oxygen-silane chemistry. This is achieved by continuous sputter etching of the film during the deposition process. A two-step process is utilized to deposit a composite layer for higher manufacturing efficiency. The first step, which has a deposition rate of approximately 0.5 $\mu$m/min., is used to provide complete gap fill between the metal lines. The second step, which has a deposition rate of up to 1.5 $\mu$m/min., is used to deposit a total thickness of 2.0$\mu$m for the intermetal dielectric film. The topography of this composite film is very compatible with subsequent chemicl mechanical polishing(CMP) planarization processing.

• Cement Symposium
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• no.1
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• pp.56-63
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• 1973

In cement industry in which three or more raw materials are used, the proportioning of raw materials is an essential step. When the materials are proportioned, each should be as nearly homogeneous chemically and physically as conditions permit. Most of th

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.401-404
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• 2008

In the present investigation, a high precision thermal imprint system for micro ceramic products was developed and the net-shape manufacturing of multi-layer ceramic reflector for LED (Light Emitting Diode) was conducted with a precision metal die. Workpiece used in the present investigation were the multi-layer laminated ceramic sheets with pre-punched holes. The cavity with arbitrary angle was formed on the circular and rectangular holes of the ceramic sheets. During the imprinting process, the ambient temperature of the imprint system was kept over the transition temperature of the ceramic sheet and then rapidly cooled. The results in this paper show that the present method can be successfully applied to the fabrication of very small size hole array for ceramic reflector in a one step operation.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.10a
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• pp.167-170
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• 2000

This paper is concerned with development of a performance evaluation model for material handling system in cellular manufacturing system based on multi-attributes analysis method. We used the AHP(analytic hierarchy process) and fuzzy set ranking methodologies to overcome the special decision problems; those of multi -objective, multi-criterion, and multi-attributes. We proposed a 3-step approaches and we developed a systemic and practical computer program to solve the problems in the proposed methods. Computational experiments are then performed to cellular manufacturing system and show the effectiveness of the proposed model.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.241-244
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• 2004

Dimension and tolerance are very important factors both in a design stage and in a manufacturing stage. As a part of process planning, the tolerance transfer aims at determining the method for converting design dimensions and tolerances into manufacturing dimensions and tolerances based on a given drawing. A procedure for the tolerance transfer is proposed in this paper. Tolerance chart is a valuable graphical tool for a process planner to determine the manufacturing dimensions and tolerances, and consisted of several steps. Among several steps necessary for making up the tolerance chart, the methods for the identification of dimension chain, the determination of tolerances, and the calculation of operational dimensions are presented by using concepts and new presentation methods. A solution method for each step is derived which will be used to establish the tolerance transfer techniques.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.06a
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• pp.119-128
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• 1994

Until recently, Stamping tool manufacturing depend on skilled designers and technicians, because it has many parameters. So, Try-out time not controlled. We now apply CAE, preliminary experiment, material database and automated stain measurement in stamping tool manufacturing for concurrent engineering that decreases product development circle time, saves cost, improves product reliability. Automated strain analysis and measurement environment gives very accurately informations to technicians of stamping tool manufacturing. They analysed the part in problem and appled to results in Try-out step.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.921-926
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• 1997

SOI(Silicon On lnsulator) technology is many advantages in the gabrication of MOS(Metal-Oxide Semiconductor) and CMOS(Complementary MOS) structures. These include high speed, lower dynamic power consumption,greater packing density, increased radiation tolearence et al. In smiple form of bonded SOL wafer manufacturing, creation of a bonded SOI structure involves oxidizing at least one of the mirror polished silicon surfaces, cleaning the oxidized surface and the surface of the layer to which it will be bonded,bringing the two cleanded surfaces together in close physical proximity, allowing the subsequent room temperature bonding to proceed to completion, and than following this room temperature joining with some form of heat treatment step,and device wafer is thinned to the target thickness. This paper has been performed to investigate the possibility of the bonded SOI wafer manufacturing Especially, we focused on the bonding quality and thinning method. Finally,we achieved the bonded SOI wafer that Si layer thickness is below 3 .mu. m and average roughness is below 5.angs.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.166-171
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• 2007

In this paper Research development about a micro metal forming manufacturing system has been developed. A micro forming system has been achieved in Japan and it's developed micro press is limited to single forming process. To coincide with the purpose to be more practical, research and development is necessary about the press which the multi forming process is possible. We set the development of the equipment including micro deep drawing, micro punching and micro restriking process to the goal. To achieve this goal, we set the application product to a micro thin foil valve which is used in the micro pump module. The compound die set has been designed and manufactured to make two step process. The material of thin foil valve is SUS-304 and its thickness is 50$\mu$m. We can get a good forming results from micro punching experiments in this paper.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.759-762
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• 2000

In order to reduce lead-time and cost, recently the technology of Rapid Prototyping and Manufacturing (PR/M) has been used widely. So various RP/M methods have been developed and these systems commercialized several years ago. But we have carried out rapid product, such as sphere, by the milling process instead of RP system. in the case of sphere with three-dimensional shape. the machining method using conventional milling machine has resulted in some troubles because of its deformation and lack of stiffness which is due to usual work piece set up method. In this paper, the feasibility of milling process which is divided into two steps such as the-upper-and-1ower-face milling process using supporting material were investigated and suggested.