銅蝕刻液及氯酸鈉蝕刻液本質與酸不相容之熱危害探討

Thermal Hazard Evaluation on the Nature and Incompatibility of Industrial Etching Solution

現今台灣面板產業蓬勃發展，隨著消費者對於電視與手機等產品之螢幕尺寸及高精細畫質要求，使得本產業製程不斷的演進與改良。蝕刻製程係將進行微影製程前所沈積的薄膜，以化學反應或物理作用將未被光阻覆蓋保護的區域清除，本製程依作業特性及方式不同，區分為乾式蝕刻及濕式蝕刻。其中，濕式蝕刻屬於液相及固相間的化學反應，其利用蝕刻液的化學反應將未覆蓋光阻區域的基材移除，並在完成蝕刻反應後，由溶液攜走腐蝕雜質達到剝除效果。面板廠等高科技產業因製程需求使用各類危害性化學品，若使用不慎可能導致面板廠之事故。其中，廠務供料系統為廠內化學品之供需要角，在物料傳輸、機台運作乃至於廢液處理時需評估物質潛在的物化性反應，以防止化學品洩漏、廢液處置不當及誤入料時可能產生之危害。本研究選擇科技廠蝕刻製程機台常見之蝕刻液：銅蝕刻液（含過氧化氫與酸液）與氯酸鈉蝕刻液進行熱分析比較，並探討廠務供料系統遭遇酸性物質（硫酸、鹽酸、硝酸）時可能產生之酸催化與不相容性反應。本研究藉由微差掃描熱卡計（Differential Scanning Calorimetry, DSC）進行動態昇溫速率之熱分析實驗與不相容性測試，以求得蝕刻液之相關熱力學數據，如放熱起始溫度（T0）、峰值溫度（Tp）以及放熱量（ΔHd），並估算蝕刻液放熱反應之動力學參數與自放熱模式。實驗結果顯示銅蝕刻液相較於氯酸鈉蝕刻液有較低的放熱起始溫度及較高的放熱焓值，針對銅蝕刻液在硫酸、鹽酸、硝酸等三種酸催化狀況下，於硝酸誤入製程機台、管線中產生的危害性較大；而針對氯酸鈉蝕刻液則是在硫酸與鹽酸誤入製程機台與管線時可產生較高的危害風險，故科技廠應建立對蝕刻製程之溫度與物質濃度偵測、反應物質相容性及溶液混合等危害辨識與製程防護技術，若再加以良好的製程安全管理與緊急應變措施，將可確保製程避免熱反應危害之風險。

With increasing in the screen size, and the demand for high-definition image quality and high resolution for optoelectronic industry, various chemicals or physical processes are constantly evolving and improving. The etching process is performed for a film deposit before the lithography process, and cleans the area without the photoresist by using chemical or physical reactions. It can be divided into dry etching and wet etching depending on the characteristics and manner of operation. Wet etching belonging to the reaction between liquid and solid phases is a chemical process using an etching solution for removing the substrates without covered by the photoresist region and the corrosive residuals from the solution after the etching reaction is completed. TFT-LCD industry has a safety concern of the reactive materials due to the process demands for many hazardous chemicals, which may cause harmful, fire or explosion incidents in case of wrong operation. The facility supply systems in the factory are using various reactive chemicals that should establish safe management and protection. Moreover, chemical supply operation systems need to be carefully planned in order to prevent possible failures from tanks or pipelines, and improper handling or mixing of hazardous materials. This study tested two etching solution (H2O2/acids and NaClO3) which are widely used in electronics factory for wafer cleaning or thin-film etching. However, the acidic and oxidants substances, may be encountered thermal hazard. Thermal dynamic scanning of DSC (Differential Scanning Calorimetry) was used to analyze exotherm and incompatibility of two etching solution and reacting with themselves and H2SO4, HCl and HNO3. The calorimetric data, such as exothermic temperature (T0), the peak temperature during exotherm (Tp), heat of reaction (ΔHd), were evaluated the reaction kinetics and self-heating model.