• Journal of Institute of Control, Robotics and Systems
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• v.19 no.12
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• pp.1072-1080
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• 2013

In a the present day, many vision inspection techniques are used in productive industrial areas. In particular, in the semiconductor industry the vision inspection system for wafers is a very important system. Also, inspection techniques for semiconductor wafer production are required to ensure high precision and fast inspection. In order to achieve these objectives, parallel processing of the inspection algorithm is essentially needed. In this paper, we propose the GPU (Graphical Processing Unit)-based parallel processing algorithm for the fast inspection of semiconductor wafers. The proposed algorithm is implemented on GPU boards made by NVIDIA Company. The defect detection performance of the proposed algorithm implemented on the GPU is the same as if by a single CPU, but the execution time of the proposed method is about 210 times faster than the one with a single CPU.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.357-358
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• 2006

We propose the robust PBFLMS in noises, which is the enhanced acoustic echo canceller using ACPBF-LMS(Alternative Constrained Partitioned Block Frequency domain Least Mean Square) algorithm. The defect of the block structure filtering is the deterioration of convergence efficiency from noise and interference. To improve the performance of convergence efficiency, noise effect should be reduced. The new method of reducing noise effect is proposed, which apply the estimated background noise to adaptive filter step size. By experiments, the proposed acoustic echo canceller has TCL of 50dB, and always provides faster convergence speed and lower complexity than the full-tap NLMS. We also carried out an implementation of PBFLMS using ARM9EJ-S.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.151-152
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• 2007

본 논문은 TFT-LCD 영상에서 결함을 자동검색하여 결함이 있는 LCD 영상의 경우 결함이 있는 LCD 패턴을 정확하게 추출해 내는 방법을 제안하였다. TFT-LCD 영상에서 결함이 있는 LCD 패턴 검색은 세단계로 이루어진다. 1단계는 먼저 입력영상에서 LCD 패턴영상의 특징을 이용하여 각 LCD 패턴의 기준점을 찾는다. 2단계는 1단계에서 찾은 여러 기준점 중에서 필터링과정을 통하여 정확한 한 개의 기준점을 최종 선택한다. 마지막으로 3단계에서는 최종적으로 선택된 기준점을 이용하여 결함정의(결함중심 및 결함사이즈)를 이용하여 결함이 포함되어 있는 LCD 패턴을 추출한다. 제안된 결함패턴 추출 알고리즘의 정확성은 컴퓨터 시뮬레이션을 통하여 그 효용성을 증명하였다.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.149-150
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• 2007

In this paper, we propose a novel defects inspection algorithm for TFT-LCD panels. We first compensate the distorted image caused by the camera distortion and the uneven illumination environment using the least squares method and the bezier surface. We find a starting point of each pattern. The reference frame, made by subtract method using several clean patterns, is compared to each pattern to find defects. The simulation example shows that our algorithm not only inspects the defects well, but also is robust to the 1-pixel error.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2485-2487
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• 2000

In this paper, we use a fuzzy algorithm to detect and diagnose the error which is caused by time delay of the computer-controlled system. Generally, a computer-controlled system is composed of computer and process. And they communicate the data each other. In data communication, error occurs by some reasons, such as noise, disturbance, hardware defect, etc. Time delay is one of the reasons. And time delay makes it difficult to distinguish whether the system really has a problem or not. Therefore, we need to detect and diagnose the error from time delay. For difficulty of modeling and ambiguity of classification, we use a fuzzy algorithm. To verify the better performance of the proposed algorithm, we exemplified by some simulation results.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.441-442
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• 2007

We deposited nickel oxide(NiO) thin films on silicon(Si) substrates at Room temperature and $500^{\circ}C$ using a nickel target by reactive DC and RF sputtering. In addition, we anneal to NiO thin films deposited at room temperature. Using spectroscopic eillipsometry, we obtained optical characteristics of every films. We discussed relations of the optical and structural properties of NiO thin films with the oxygen flow rate, substrate temperature and annealing temperatures. Refraction was decreased and defect was increased when NiO thin films was annealed. We also analyzed the electrical characteristics of NiO films which deposited DC and RF sputtering method.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.09a
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• pp.35-40
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• 1998

There have two kinds of defects, planar defects and vertical defects which were called micropipes in SiC bulk crystals grown by a sublimation method. We could decrease these defects by adding a little piece of Si in the SiC powder or using Ta cylinder in the crucible. so were report the dependence of these defects in a wafer on silicon/carbon ratio in this paper. The chemical species sublimed from SiC powder is affected by carbon from the graphite wall of the crucible. It is important to control the chemical species on the substrate.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.245-251
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• 2005

Ship's auto pilot is must necessary the azimuth data, which is supported by a gyro, geomagnetism and GPS compass. The gyro compass is operation of stability & correct , therefore it is used by big size shipping because of high cost. The other side, medium and small size shipping are used the geomagnetism and GPS compass of low cost. This paper have studied that the two jobs are going on at the same time both of there's advantage. Which is asked the algorithm for stability azimuth data on reject methode the defect of respect with geomagnetism & GPS compass.

• Journal of Surface Science and Engineering
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• v.48 no.3
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• pp.126-130
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• 2015

A high-pressure depletion method using plasma chemical vapor deposition (CVD) is often used to deposit hydrogenated microcrystalline silicon (${\mu}c-Si:H$) films of a low defect density at a high deposition rate. To understand proper deposition conditions of ${\mu}c-Si:H$ films for a high-pressure depletion method, Si films were deposited in a combinatorial way using a multi-hollow discharge plasma CVD method. In this paper the substrate temperature dependence of ${\mu}c-Si:H$ film properties are demonstrated. The higher substrate temperature brings about the higher deposition rate, and the process window of device quality ${\mu}c-Si:H$ films becomes wider until $200^{\circ}C$. This is attributed to competitive reactions between Si etching by H atoms and Si deposition.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3048-3050
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• 1999

This paper suggests a position estimating algorithm using mono vision system with projective geometry method. Generally, 3-D information can not be easily extracted from mono vision system which is taken by a camera at a specific point. But this defect is overcome by adopting model-based image analysis and selecting lines and points on the ground as natural landmarks. And this paper suggests a method that estimates position from many natural landmarks by distance error weight function.