某彩色濾光片廠的潔淨室內揮發性有機氣體濃度分佈研究

Abstract

彩色濾光片(Color Filter, CF)於製程中大量使用揮發性有機溶劑，在機台運轉過程與預防保養作業(Preventive Maintenance, PM)中，因機台設備局部排氣系統捕集氣體效率不佳及PM人員不良工作習慣均會導致揮發性有機氣體逸散至潔淨室環境中，造成勞工健康之危害。本研究主要目的在於建立某個CF廠的揮發性有機氣體物種及濃度分佈資訊，提供CF廠改善潔淨室環境空氣品質與推動職業安全衛生管理之參考。

本研究首先對某一CF廠進行製程設備及化學品使用調查與收集，用來評估鑑別出有機溶劑作業區，以規劃揮發性有機性氣體區域採樣點，並採用美國環保署所公告TO-14不鏽鋼筒採樣及氣相層析質譜儀(GC/MS)分析方法，進行固定點的區域採樣與分析。透過GC/MS對揮發性有機氣體定性與定量分析結果，可了解揮發性有機氣體濃度高於半導體製造設備安全指引(SEMI S2)所建議1%容許濃度標準之作業區，並藉以規劃出二十一位作業勞工，進行個人暴露濃度採樣與分析。

CF廠製程作業區主要使用的有機溶劑環己酮、丙二醇單甲基醚(PGME)與丙二醇單甲基醚酯(PGMEA)，廣泛使用於PM清潔擦拭溶劑的異丙醇、丙酮及乙醇。GC/MS分析結果發現，揮發性有機氣體濃度皆小於我國法定容許濃度標準。在十個區域採樣測點中僅有兩個區域採樣點環己酮濃度小於0.25ppm (即SEMI S2的1%容許濃度建議標準)，其餘各點均超過SEMI S2的1%容許濃度建議標準; 有兩個區域採樣點的PGMEA超出1 ppm (即SEMI S2的1%容許濃度建議標準)，其餘各點均低於SEMI S2的1%容許濃度建議標準。至於在各區的其他污染物的濃度，都均遠低於SEMI S2的1%容許濃度標準。在個人採樣分析結果顯示，六個區域潔淨室作業之勞工有機溶劑暴露濃度均符合我國法定公告暴露容許濃度標準，僅有三位作業場所勞工異丙醇及丙酮超過SEMI S2的1%容許濃度建議標準。

本研究建立CF廠潔淨室空氣中揮發有機性氣體物種及濃度分佈數據，可作為既有與新建中的彩色濾光片廠改善潔淨室空氣品質的參考依據。

關鍵字: 彩色濾光片、揮發性有機氣體、區域採樣、SEMI S2

In the Color Filter (CF) Fab, large amounts of volatile organic solvent are used in the manufacturing processes. Volaticle organic gases are emitted into the clean room during operation and preventive maintenance (PM) due to poor efficiency of the ventilation system and bad working habits of PM personnel, posing threat to labors’ health. The aim of this research is to find out the species and concentration distribution of volatile organic gases in a CF clean room. The data are intended to be used for improving the air quality in the clean room and give impetus to occupational health and safety management.

In this research, equipments and chemicals used in the CF plant were investigated and to clearly identify the organic solvent working areas and plan the corresponding fixed sampling points. The US EPA TO-14 method with stainless steel canisters was used for sampling and GC/MS analysis was adopted. The results of GC-MS analysis identifed the areas where volatile organic gas concentration was higher than 1% of the Permissible Exposure Limit (PEL) suggested in SEMI S2. Then, 21 workers were selected for personal sampling and analysis.

The primary organic solvents used in the manufacturing processes are cyclohexanone, PGMEA and PGME, while isopropanol, acetone, and isopropyl alcohol are widely used for wipe-cleaning in PM. GC/MS results show all measured volatile organic concentrations are belw the Taiwan’s PELs. The cyclohexanone concentration is less than 0.25 ppm (or below 1 % PEL suggested in the SEMI S2 standard) at two of the ten sampling points, while the cyclohexanone concentration at the other points exceeds 1 % PEL of the SEMI S2 standard. For PGMEA, the concentration is higher than 1 ppm (or above 1 % PEL suggested in the SEMI S2 standard) at two of the ten sampling points, while the concentrations at the other points are lower than 1 % PEL of the SEMI S2 standard. For other VOCs, the concentrations at all sampling points fall far below 1﹪PEL. The personal exposure study shows that VOC exposure at six areas of the clean room meets the Taiwan’s PEL. Only the exposure concentrations of isopropyl alcohol and acetone of three workers exceed 1% PEL of SEMI S2 standard.

This research has established the species and concentration distribution of volatile organic gases in the clean room of a CF fab. The results are useful for improving the air quality in the clean room of the existing and new CF fabs.

Key words: Colored Filter, Volatile organic gas, Areas Sampling, SEMI S2