以碲化鉍為基礎的熱電材料具有室溫下最突出的熱電性質，但是當其與銲錫發生反應時將生成SnTe此介金屬化合物，嚴重威脅銲料接點的電性質與機械性質。除了在熱電元件表面鍍鎳作為擴散阻障層之外，改變銲料的成分試圖抑制或是減緩SnTe的生成亦是可行的方法。

本研究將針對液態錫銀銲料與熱電材料的主元素碲之間的界面反應，探討在相同反應溫度250 ℃之下，不同銀添加量以及不同反應時間對介金屬化合物的厚度和形貌的影響。結果顯示在銲錫中添加超過1 wt.%銀元素，反應界面將生成Ag2Sn3Te5以及Ag3Te2介金屬化合物阻擋液態銲錫與碲基材的直接接觸反應，達到抑制SnTe成長的效果，即使反應時間長達300分鐘，SnTe的厚度維持在11 □m，遠比純錫銲料所生成的570 □m來得少。當錫銀銲料與碲基材一產生接觸便生成Ag3Te2與SnTe，但是Ag3Te2進一步地與銲料中的錫發生反應再生成Ag2Sn3Te5以及SnTe，因此反應初期觀察到SnTe異常增厚、反應後期SnTe的生長受到抑制。

另外在本實驗中發現，當SnTe相的厚度不再增加時將進行保守場的熟化作用，隨著反應時間增加SnTe與銲料的界面形貌越來越不平整，SnTe顆粒產生明顯粗化現象。藉由俯視的電子顯微影像觀察，計算出SnTe平均顆粒半徑大致隨反應時間的1/3次方增加，與理論推測結果相符。

Telluride-based thermoelements can react with Sn-contained solders and form SnTe intermetallic compounds that may deteriorate electrical and mechanical properties of soldered junctions. In addition to the diffusion barrier approach, chemical composition of the solder alloys could be adjusted to suppress or decrease the rate of SnTe formation.

In this study the effects of Ag addition (0.1, 1, 3.5, 5 wt.%) in pure Sn on the interfacial reaction between molten solder and Te substrate is explored. It is found that the thickness of SnTe compound is reduced after soldering reaction when more than 1 wt.% Ag is added into Sn solder. For an identical time of 300 minutes, the SnTe thickness is decreased from 570 □m for a pure Sn and Te reaction to only 11 □m for a Sn-Ag alloy and Te reaction. The suppression of SnTe compound formation is associated with the presence of Ag3Te2 and Ag2Sn3Te5 ternary compounds that are located in between the SnTe compound and the Te substrate. However, the rate at which SnTe initially forms is enhanced as the formation of SnTe originates from two different sources: byproduct of molten solder and Te substrate (Ag3Te2 and SnTe) and excess SnTe when Ag3Te2 further reacts with Sn in the solder (Ag2Sn3Te5 and SnTe).

When the thickness of SnTe remains essentially constant, SnTe undergoes a conservative ripening, resulting in surface roughening. Based on top-view scanning electron microscopy micrographs, it is calculated that SnTe particles size increase approximately with the cube root of reaction time.

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