Until now, because a new product (or facility) launched in market has been retired from one year of age, we can have had ASL by stub-curve method by Iowa curve. Recently, many innovative products with important role in market like display and solar-cell etc. are more durable and, what are better, they have the constant variance in ASL because of their good quality. Of course, there are some ones like smart mobile phone with relatively big dispersion in ASL. Estimating ASL of products like display and solar-cell etc., the new approach is needed. In this paper a new method applied traditional Iowa curve with accelerated reliability test (indoor/outdoor) etc. is proposed.

In recent years, anti-PID (Potential Induced Degradation) technologies have been studied and developed at various stages through- out the solar value chain from solar cells to systems in an effort to enhance long-term reliability of the photovoltaics (PV) system. Such technologies and applications must bring in profits economically for both manufacturers of solar cell/module and investors of PV systems, simultaneously for the development of the PV industry. In this study two selected anti-PID technologies, ES (modification of emitter structure) and ARC (modification of anti-reflective coating) were compared based on the economic features of both a cell maker with 60MW production capacity and an investor of 1MW PV power plant. As a result of this study, it is shown that ARC anti-PID technology can ensure more profits over ES technology for both the cell manufacturer and the investor of PV power plant.

In recent years, there has been developed anti-PID technologies(Potential Induced Degradation) in various levels from solar cell to module and to system to enhance of the long life reliability of photovoltaics(PV) system. Such technologies must economically ensure profits for both manufacturers of solar cells and investors of PV system simultaneously for PV industry development. This paper describes a comparison between and selection from two anti-PID technologies in the solar cell level, ES(modification of emitter structure) and ARC(modification of anti-reflective coating) based on the economic features of anti-PID solar cell production system with 60MW capacity for a solar cell maker and a 1MW PV power plant installed with PV modules using anti-PID solar cells. From the comparison between ES and ARC, it is shown that ARC anti-PID technology can make more profit for both a solar cell maker and a PV power plant investor.

When monitoring an instrumental process, one often collects a host of data such as characteristic signals sent by a sensor in short time intervals. Characteristic data of short time intervals tend to be autocorrelated. In the instrumental processes often the practice of adjusting the setting value simply based on the previous one, so-called ‘adjacent point operation’, becomes more critical, since in the short run the deviations are harder to detect and in the long run they have amplified consequences. Stochastic modelling using ARIMA or AR models are not readily usable here. Due to the difficulty of dealing with autocorrelated data conventional practice is resorting to choosing the time interval where autocorrelation is weak enough then to using I-MR control chart to judge the process stability. In the autocorrelated instrumental processes it appears that using the Shewhart chart and the time interval data where autocorrelation is relatively not existent turns out to be a rather convenient and very useful practice to determine the process stability. However in the autocorrelated instrumental processes we intend to show that one would presumably do better using the EWMA control chart rather than just using the Shewhart chart along with some arbitrarily intervalled data, since the former is more sensitive to shifts given appropriate weights.

Solar-cell Wafer 제조 공정에서는 각 공정 별로 품질 특성과 운전 조건을 측정하고 있다. 하지만 개별 이력추적이 되고 있지 않아 Input 정규성에 대한 부문이나, 선공정과 후공정 사이의 인과성, 공정 흐름에 따른 영향 파악이 힘든 실정이다. 공정 분석과 개선을 위해서는 특성치의 측정뿐만 아니라 공정 추적성의 확보가 필요하다. 99% 이상의 양품율을 유지하고 있는 공정이라도 인과성 확립 체계가 구축되어 있지 않다면 통계 분석 등을 이용한 공정 관리나 개선이 불가능하다. Marking System 구축으로 공정 추적성이 확보된다면 인과 분석 등 통계 분석을 활용한 공정 관리 및 개선으로 등급의 상향과 고효율, 고출력 제품 양산이 가능하며 보다 더 진보된 공정 관리 능력을 가질 수 있을 것으로 사료된다. Edge Isolation 공정을 중심으로 Laser Marking Machine를 이용하여 사이클타임의 손실 없이 각 Wafer의 소재입고부터 각 공정에 있어 이력추적이 가능하고, 샘플 기법과 Laser의 특성을 잘 활용할 수 있는 경제적이고 효율적인 Wafer Marking System을 개발하는 것이 이 연구의 목적이다.

MES(manufacturing execution system)란 생산을 수행하기 위해 사용되는 방법과 도구들을 포함하는 온라인 통합 생산 시스템으로 주문 받은 제품을 최종제품이 될 때까지 생산 활동을 최적화 할 수 있는 정보를 제공하며 정확한 실시간 데이터로 공장 활동을 지시하고, 대응하고, 보고 한다. 이에 따라, 공장에서 가치를 제공하지 못하는 활동을 줄이는 것과 함께 변화에 빨리 대응할 수 있게 함으로써 공장 운영 및 공정의 효과를 높인다. 또한 납기, 재고회전율, 총수익, 현금 흐름 등을 개선 할 뿐 만 아니라 운영 자산에 대한 회수율도 좋게 하며, 양방향 통신으로 기업 전체 및 Supply Chain에 걸쳐 생산 활동에 대한 중요한 정보 들을 제공한다. 선행적 관리는 대응적(active), 예방적(preventive), 예측가능(predictive)으로 이루어진다. 선행적 관리가 MES에 포함되어 구성된 System 설계를 본 연구에서 제안했고, 이에 대한 기존의 MES와의 차별성 및 효율성에 대한 것을 검증했다.