本論文研究中，主要模擬引腳架之不同形狀基材對於錫鬚晶生長之影響，同時考慮在不同操作環境條件下對於錫鬚晶生長之情形。實驗方式為將銅基材先以萬用試驗機將其彎曲90°，其後以電鍍的方式將霧錫電鍍於基材上。改變電流密度觀察鍍層之性質，並將各試片放置於不同溫度以及不同時效時間下，以統計方式來探討不同形狀之基材在不同環境下對於錫鬚晶生長之影響。結果顯示，鍍層厚度將會隨電流增加而呈現線性增加；鍍層結構亦會隨電流密度之不同而有所改變。在不同形狀基材之影響，在凹面區域以及其兩側平面所受到之壓縮應力會促使錫鬚晶之生長；而在凸面區域以及其兩側平面所受到拉張應力會抑制錫鬚晶之生長。在不同形狀基材對不同電流密度之影響，因鍍層厚度與鍍層結構之影響，其鬚晶之數量與長度是隨電流密度的增加而呈現V型趨勢。此外，亦發現不同厚度之鍍層在彎曲形狀下所造成之殘留應力程度將會有所不同，而影響後續錫鬚晶之影響。在不同溫度時效處理下，其結果顯示錫鬚晶的數量與長度皆會隨著溫度的增加而減緩。其因為在高溫環境下，將會使試片產生退火現象而使鍍層內之應力釋放：並且在高溫環境下亦能夠使鍍層表面之氧化層增厚來作為使錫鬚晶生長之阻障層，使鬚晶形態偏向生成凸塊狀之錫鬚晶。
由本論文之結果分析，證實對於不同形狀之基材確實能夠影響錫鬚晶之生長。此外，若在條件之許可下，建議使用10、15 ASD之電流密度之鍍錫層來作為引腳架之修飾，其能形成凸塊結構之鬚晶形態，較不容易在元件中產生架橋現象而導致元件之失效。

In this study, shape effect on substrates for Sn whisker growth has been investigated. Cu foils as substrates were bent to 90 degree by universal testing machine. Matte Sn layers were electroplated on the substrate under various current densities. Therefore, the surface morphology and thickness of the Sn layers are different. Then, the samples were taken heat treatment under different temperatures for various periods of aging times. Statistics methods are applied to calculate the number and length of Sn whiskers and find out the Sn whisker distribution. The results indicate that Sn whisker growth was promoted by the compression stress in the convex sides and was restrained by the tension stress in concave sides. Due to the effect of various plating thickness and structure, the number and length of Sn whiskers were presented V-shape tendency as increasing the current density. Meanwhile, the different residual stresses were found in the different bent shape area with the various Sn layer thicknesses. For the increasing of plating thickness in electroplating process offered the extensive residual stress to mitigate or promote the Sn whisker. The number and length of Sn whiskers were alleviated as the high heat-treated temperature which alleviated the stress in plating layer. Increasing the aging temperatures also enhanced the thickness of oxide layer. Thick oxide layers can prevent Sn whisker growth.
The experimental results can be concluded that the different shape substrate in matte Sn systems influence Sn whisker growth. To ensure the reliability of products, electroplating Sn layers are recommended to use the medium current density. Sn whiskers with hillock type are found in this plating condition. The hillock type Sn whisker does not tend to form bridging phenomenon lead to fail of devices.

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