無塵室揮發性有機氣體異味調查探討 -以某晶圓級封裝廠為例

Investigation of the Source and Distribution of Volatile Organic Compounds in Clean Rooms of a Wafer Level Packaging Factory

應志霖(Chih-Lin Ying)

指導教授 ： 林居慶

國立中央大學/工學院/環境工程研究所/碩士(2015年)

摘要

晶圓級晶片尺寸封裝(Wafer Level Chip Scale Package)製程如同半導體前段製程，於生產線上會大量使用到揮發性有機溶劑，若在機台運轉與預防保養作業(Preventive Maintenance, PM)的過程中，因生產設備局部排氣系統的捕集揮發性有機氣體效率不佳，以及設備維修人員與PM人員具有不良之工作習性時，皆會導致揮發性有機氣體逸散至無塵室作業環境中，造成生產作業環境異味飄散損及勞工健康危害問題。然而，過往的研究多偏重於半導體及液晶面板的製程安全危害評估研究，對於年產值高達2,200億以上的半導體後段封裝產業則相對投入較少的評估研究與探討，因此本研究之主要目的即著重在調查與瞭解晶圓級晶片尺寸封裝製造廠無塵室作業環境空氣中揮發性有機氣體物種及其分佈濃度狀況，並透過採樣分析結果比對其是否符合我國勞工安全法令現行的作業環境容許濃度標準及SEMI S2的建議標準。調查的方法乃是依晶圓級晶片尺寸封裝製造廠使用有機溶劑區域，規劃出數個「不鏽鋼採樣筒採樣之氣相層析質譜儀分析」，偵測鑑別出揮發性有機氣體物種及濃度。並搭配光游離偵測器直讀儀(Photo-Ionization Detection, PID)量測各點之總揮發性有機物(Total Volatile Organic Compound, TVOC)數值，以作為改善之依據。
研究結果顯示，在原物料MSDS內容物調查方面，實廠MSDS內容物成分揭露率達80%以上者僅有49.2%，此與國內其他學術單位研究調查所得的僅有38%進行危害分析相較，整體原物料MSDS內容物揭露率同屬偏低之列；而在作業區的有機揮發性化學品調查方面，以IPA、丙酮為原物料使用之大宗，且由全廠82個PID量測點所得之數據來看，在一般區域的60個量測點中，僅少數點數於改善初期有超過7 ppm，其餘皆在改善目標值內；在有機化學品異味區域，TVOC異味逸散問題的改善速度以5F的黃光及蝕刻區為最快，最慢的為3F Wet Bench區，而TVOC長期監測值最高值的高低排序依序為3F Wet Bench區、3F黃光區、3F蝕刻區及4F膠合區；在委外GC/MS環境檢測結果，雖然7處作業區的乙醇、丙酮及異丙醇濃度的檢測值皆低於國內法規標準值的要求，但值得注意的是：(i)乙醇量測的濃度於4F膠合區為18.51 ppm，超過SEMI S2訂定的1% OEL值4 ppm、(ii)丙酮量測濃度於3F Wet Bench區的7.70 ppm及5F蝕刻區的67.06 ppm兩處皆超過SEMI S2訂定的1% OEL值7.5 ppm及達到嗅覺閾值的覺察值範圍、(iii) IPA異丙醇量測濃度於3F Wet Bench區的4.29 ppm也超過SEMI S2訂定的1% OEL值4 ppm；最後，在驗證作業區環測數據逐年改善成效方面，在不同樓層、作業區域的九個環測點中，有高達七個環測點有明顯之改善關係，另兩個環測點前後期改善比較為持平現象。

關鍵字

晶圓級晶片封裝 ； 揮發性有機氣體 ； TVOC 氣態污染來源 ； PID 光游 離偵測器直讀儀

並列摘要

Similar to the front-end development of semiconductors, the (back-end) manufacturing process of Wafer Level Chip Scale Packaging (WLCSP) uses a tremendous amount of volatile organic compounds (VOCs), which may potentially cause a higher health risk to the employees in clean rooms when VOC spreading-out incidents occur due to that the local exhaust ventilation capacity is insufficient or the person in charge of preventive maintenance is incompetent during the process. Surprisingly, while considerable work on the safety or hazard assessment of the semiconductor and liquid crystal panel production has been conducted, litte work has been undertaken analyzing these issues for the WLCSP industry, even though the gross of this industry is 220 billions a year. As such, the purpose of this research was to investigate the level and distribution of VOCs in the operating clean room of a WLCSP factory through sampling and analysis, and to ensure that the standards established by both of the Labor Safety and Health Law as well as SEMI S2 would be met. For this purpose, Photo-Ionization Detection (PID) and GC/MS were used to quantify the level of the total volatile organic compound (TVOC) and identify the VOC species.
Investigation results indicate that for the material safety data sheet (MSDS) of the raw materials, only 49.2% of the factories revealed more than 80% of the product composition in the MSDS, in accord with other investigations that 38% of the factories were reported to perform hazard analysis. Resuls also point out that IPA and acetone were identified as the major VOCs in the operating area, and of the 60 measurement locations in the regular area, only a few exceeded 7 ppm during the initial stage of the improvement, while the rest were well within the target of improvements. As for the areas having the TVOC odor issue, the yellow zone and the etching area on the 5th floor showed significant improvement, while the wet bench area on the 3rd floor only improved slightly. Further, the 3rd floor web bench area was dected the highest long temr monitoring values of TVOC, followed by the 3rd floor yellow zone, the 3rd floor etching area, and finally the bond zone of the 4th floor. In addition, according to the obtained GC/MS environmental measurement results, even though the levels of ethanol, acetone and IPA were all well below the legally allowed limits, they did not meet the standards established by the SEMI S2 Safety Guideline (i.e., 4 ppm for ethanol, 7.5 ppm for acetone, and 4 ppm for IPA): the ethanol level was 18.51 ppm for the Bonding Area on the 4th floor; the acetone level was 7.70 ppm for the Wet Bench Area on the 3rd floor and 67.06 ppm for Etching Area on the 5th floor; the IPA level was 4.29 ppm for the Wet Bench Area on the 3rd floor. Lastly, while verifying the effectiveness of the environmental measurement in the operating areas, 7 out of 9 areas across different floors showed significant improvements, and the other areas were kept stable.

並列關鍵字

WLCSP (Wafer-Level Chip Scale Package) ； VOCs (Volatile Organic Compounds) ； TVOC Gaseous sources of pollution ； PID (Photo-Ionization Detection)

參考文獻

﹝14﹞劉信旺等，「空氣中揮發性有機化合物分析方法」，CHEMISTRY （THE CHINESE CHEM. SOC.,TAIPEI）September. 2004 Vol. 62, No.3, pp.377~386

﹝11﹞林錦椿等，「以HACCP管控無塵室酸性氣態分子污染物之研究」，工業安全衛生月刊，西元2010年10月。

﹝1﹞陳玲君，「2014半導體產業年鑑」，工研院產經中心

﹝10﹞黃桂虹，「某TFT-LCD廠勞工環境噪音及揮發性有機溶劑暴露與健康狀況評估」，中國醫藥大學，碩士論文，西元2008年。

﹝15﹞楊玉玲，「電子業揮發性有機物排放特性及其管理之研究」，台北科技大學，碩士論文，西元2008年。