引腳型塑膠封裝（Lead Type Plastic Package, LTPP）中，外露式晶片座，經過電解去膠製程所產生之電解效應（Electrolysis），可因氫離子（H+）與電子（e-）反應產生氫氣（H2），氫氣的膨脹會掀離銅導線架晶片座與高分子材料的接合面造成界面脫層。分離式地線區的外露晶片座主要目的在避免地線區域直接受應力、電解效應與脫層之影響。本文利用有限元素（FEM）電腦分析，對LTPP不同分離式地線區的外露晶片座結構設計，進行熱應力數值模擬，藉此改善目前地線區於晶片座邊緣四周的脫層。本文以高熱應力之晶片座設計配合實驗，驗證電解效應及不同去膠製程參數對界面脫層之影響，得到（1）電解去膠製程中所施予的電壓越大脫層發生的比例越高，反之電壓越低脫層發生的比例越低，但不論電解去膠電壓高或低，均會有電解效應之影響導致脫層；（2）無電壓化學去膠的組別中，並未有任何脫層的狀況；此發現可應用於所有外露式晶片座之脫層改善。

In lead type plastic package, the hydrogen produced by the reaction of electrolysis generated hydrogen ion and electrons could cause delamination of the interface between the copper lead frame die paddle and the polymer material. This research employed finite element numerical analysis to simulate the thermal stress on the exposed die paddle structure of various designs for different LTPP isolated ground areas. The exposed die paddle in the isolated ground area was aimed to avoid the ground area being directly influenced by the stress, electrolysis effect and delamination. This in terms improved the current delamination around the ground area and the edge of the die paddle. This research used the high thermal stress die paddle design in the experiments to verify the impact of the electrolysis effect and different de-flash process parameters on the interface delamination. The conclusions were first the higher voltage used for the electrical de-flash process resulted in higher percentage of delamination and lower voltages caused less percentage of delamination phenomenon. However delamination occurred regardless of the extent of applied voltages. Second, no delamination was observed in non-electrolysis chemical de-flash process cell. Such discovery can be applied to improve all exposed die paddle delamination.

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