高科技設備搬運及運送安全風險評估

Abstract

近年來半導體科技產業蓬勃發展，各家業者為了強化本身製造優勢，無不朝向製程微縮或增加產量的方式來降低生產成本並維持獲利。設置一座12吋晶圓廠就至少包含了200~300多種設備機台，其中微影設備(Litho equipment)掃描式曝光機(Scanner)因每部平均單價約為新台幣10億元以上，又佔了建廠成本的大宗；因此確保該設備能妥善安裝就成了非常重要的課題。 本研究是針對微影設備之搬運與運送安全進行探討，並依據近年來相關作業事故案例就微影設備之出貨、運輸以及顧客端安全卸貨等各項步驟，以失誤模式與效能分析手法(Failure mode and effective analysis, FMEA )與工作安全分析(Job safety analysis , JSA)手法結合將各研究標的風險與可能性加以量化，並將評估屬於不可接受之風險(>50分)之作業列管。對於不可接受風險項目以消除、取代、工程控制、管理控制及個人防護具等優先順序改善，並考量現有技術能力及可用資源等因素，採取有效降低風險的控制措施以將風險降至可接受及防範之標準；最後再加入偵測度的評估因子，藉以確認採取控制措施後的殘餘風險(風險優先數)是否已降至列管值以下，以評估風險控制措施的有效性。 文中鑑別出氣墊貨櫃失火，屬微影設備搬運與運送作業中之不可接受風險；在經由火災動態模擬應用程式比對後，藉由模擬溫度場、速度場、火流方向、煙流擴散等狀況所取的之數據，實驗中發現火災發生後的第70秒，這時的溫度已經會讓貨櫃內之精密設備產生變化，再加上煙霧沈降時間在41秒時就會影響到設備表面，如果要搶救設備就必需在41秒內將設備拉出來。由此氣墊貨櫃(System container)並據此進行風險控制措施的推動，除針對貨櫃中的設備進行本質防火安全改善外，並經氣墊作業之工作安全與設備防護標準化，另安排相關作業人員於作業前進行相關訓練與演練；藉由上述風險控制措施的實施，以增加安全防護層(protection layer)的方式來減少微影設備搬運與運送上風險(Tool move in safety risk assessment)；搬運公司與研究設備商參照此研究建議進行改善後，將此次風險由等級2(不可接受風險)一直降到等級4(可以接受之風險)。自2011年6月後迄今，未再發生相關設備搬運與運送異常問題。

In recent years, manufacturers in the semiconductor industry have spared no efforts to reduce production costs, maintain profitability, and strengthen their manufacturing advantages, by either scaling down processes or increasing production. Setting up a 12-inch wafer fabrication plant requires 200 to 300 types of equipments, among which the lithography equipment (scanner/scanning exposure machine), which has an average unit price that is above NTD 1 billion, accounts for the majority of the setup cost. Hence, the proper installation of such equipment is an important issue. This study explored the handling and transport safety of lithography equipment. Based on recent relevant occupational accidents, FMEA (failure mode and effective analysis) and JSA (job safety analysis) techniques were used to quantify the risks and possibilities of various steps in the delivery, transportation and customer-end unloading safety of lithography equipment. A list of the jobs evaluated as having unacceptable risks (>50 points) was created for regulation. The unacceptable risk items were given suggestions for improvement regarding elimination, replacement, engineering control, management control and personal protective equipment, in the given order of priority. Meanwhile, by considering existing technological capabilities and available resources, control measures that could effectively reduce risks were established to lower the risks and match acceptable prevention standards. Finally, the directivity evaluation factor was added to confirm whether the residual risks after the adoption of the control measures had been reduced to below the regulated value, in order to assess the effectiveness of the risk control measures. It was found that the situation of the air cushion container catching fire was an unacceptable risk during the handling and transport of lithography equipment. After a comparison of the FDS application program, the experimental results showed that the temperature at the 70th second after the breakout of a fire would result in changes to the precision equipment inside the container, according to the simulated data. Meanwhile, the equipment surface would be affected by smoke damage at the 41st second. Hence, to rescue the equipment, it should be shifted out of the container within 41 seconds of a fire breaking out. Therefore, in addition to the fire safety improvements of the equipment inside the container, the air cushion job-related safety procedures and equipment protection should be standardized, and the relevant operating personnel should undergo job-related training and drilling. With the implementation of the above mentioned risk control measures, the handling risk of lithography equipment can be reduced by means of increased safety protection layers. After the transportation companies and equipment developers implemented the aforementioned suggestions proposed by this study, the risk was reduced from Level 2 (unacceptable risk) to Level 4 (acceptable risk), and no abnormalities related to the transportation and handling of the equipment were reported after June 2011.