本研究同時針對個別接點，搜尋整理文獻中界面反應與相關材料的相平衡資料。針對個別接點相關資料蒐集整理了Cu/Sn-Cu、Cu/Ag-Sb , Sn-Cu/Ni、Ag-Sb/Ni 及Ni/Bi2Te3。由於針對Cu/Sn-Cu、Sn-Cu/Ni與Ag-Sb/Ni三個系統，文獻中已有許多關於界面反應與相平衡的資料，因此不多加深入探討。由於目前並未有對於Cu/Ag-Sb 相關系統之討論，因此本文將針對此系統之界面反應及相平衡進行研究。同時因Cu與Ni能生成連續固溶體(Isomorphous system)，為提供完整的了解，本研究亦將探討Cu/Bi2Te3及Ni/Bi2Te3接點的界面反應速率的比較與相平衡。因此共將針對Cu/Ag-Sb 、Cu/Bi2Te3 Ni/Bi2Te3反應偶進行實驗探討，數據結果則搭配文獻或實驗相圖輔助分析。
研究結果發現用電鍍法Cu/Bi2Te3偶於280°C熱處理進行固相/固相反應，會形成一介穩態的過飽和相Cux(Bi2Te3)，此相於200°C及350°C均有出現，然而並未在Cu-Bi-Te相圖中觀察到。隨著時間的拉長，Cu和Te原子相互擴散形成Cu2-xTe相，Bi則以液態的形式在界面析出，大幅增加界面反應速率。Bi與Cux(Bi2Te3)過飽和相間又會形成由Bi與Bi2Te3分子相互排列的連續相 (Bi2)m(Bi2Te3)n，擴散路徑為Cu/Cu2-xTe/Bi/Bi2Te/Cux(Bi2Te3)/Bi2Te3，此反應下Cu為主要的擴散元素，相關元素相平衡分析則由現有文獻輔助分析。Ni/Bi2Te3擴散偶由電鍍法製備於280°C熱處理，則會形成NiTe2-x相及(Bi)m(Bi2Te3)n相，擴散路徑為Ni/NiTe2-x/(Bi)m(Bi2Te3)n，此反應下Te為主要擴散元素，相關元素相平衡分析則由現有文獻輔助分析。Cu/Ag-41at.%Sb 共晶銲料由電鍍法製備反應偶於300°C、500°C溫度下反應。反應在300°C下會形成明顯的Cu2Sb反應層及疏Sb的Ag3Sb-Sb兩相區，擴散路徑為Cu/Cu2Sb/Ag3Sb-Sb；在500°C下則會形成不穩定的Cu3Sb相與其分解相，以及液態冷卻形成的Cu2Sb及Ag3Sb共晶結構，擴散路徑為Cu/Cu3Sb/Cu2Sb-Ag3Sb/Ag3Sb-Sb，Sb為主要擴散元素。Ag-Cu-Sb系統之等溫恆截面相圖於300°C及500°C，則由配置不同比例合金，待其回火7至30天後取出分析而得。在300°C下6個三相區中，確立了三個相區Cu-Ag-Cu78Sb20、Cu10Sb3-Cu2Sb-Ag、Ag3Sb-Cu2Sb-Sb，而Ag-Cu78Sb20-Cu10Sb3、Ag-Ag7Sb-Cu2Sb、Ag7Sb-Ag3Sb-Cu2Sb則由觀察到的兩相區建立。在500°C下6個三相區中，確立了Ag3Sb-Sb-Liquid、 Cu-Cu3Sb-Liquid、Ag-Cu-Liquid、Ag7Sb+Ag3Sb+Liquid、Ag+Ag7Sb+Liquid、Cu3Sb+Cu2Sb+Liquid共6個三相區的存在，同時藉由兩相區的組成比例，建立出500°C下的液態相區邊界。Ag-Cu-Sb系統之二元化合物均對第三元元素無明顯溶解度，其中二元化合物中Ag7Sb對Cu的最大溶解度為4.73 at.%。

This study intends to systematically explore the phase equilibrium of the joints in the Bi2Te3 thermoelectric elements and the phase balance of the related material systems to provide a complete basic knowledge of Bi2Te3 thermoelectric elements. This study aims at individual joints, searching for the phase equilibrium data of interface reactions and related materials in the literature. The joints included in this reference review are Cu/Sn-Cu, Cu/Ag-41at.%Sb , Sn-Cu/Ni, Ag-Sb/Ni and Ni/Bi2Te3. For the Cu/Sn-Cu, Sn-Cu/Ni and Ag-Sb/Ni systems. There are many data on the interface reactions and the phase equilibrium in the literature. Therefore, this study is focused on Cu/Ag-41at.%Sb interfacial reaction and phase equilibrium. In addition, because Cu is a common solder alloy composition and electrode material, and Cu and Ni can form a complete solid solution, in order to provide a complete understanding, this study will also compare the interfacial reaction between Cu/Bi2Te3 and Ni/Bi2Te3. In this study, three systems, Cu/Ag-41at.%Sb, Cu/Bi2Te3, Ni/Bi2Te3, were investigated.
It was found that Cu/Bi2Te3 prepared by electroplating method was heat-treated at 280 °C for solid/solid phase reaction, which formed an unknown phase and did not appear in the Cu-Bi-Te ternary phase diagram. The literature was reported at 200 ° C and at 350 °C, it is judged that the saturated phase of Cu dissolved in Bi2Te3 is named Cux(Bi2Te3). For longer reaction time, liquid bismuth is participated because of the formation of Cu2-xTe. This liquid layer boosts the reaction rate. Besides, Bi layer and Cux(Bi2Te3) react to each other and form (Bi)m(Bi2Te3)n series phase stacking by Bi and Bi2Te3 molecules. The diffusion path is Cu/Cu2-xTe/Bi/Bi2Te/Cux(Bi2Te3)/Bi2Te3. Cu is the main reaction in this reaction. The related phase equilibrium refers to the recent development. Ni/Bi2Te3 diffusion couple prepared by electroplating method was heat-treated at 280 °C for solid/solid phase reaction. It forms NiTe2-x phase and (Bi)m(Bi2Te3)n phase. The diffusion path is Ni/NiTe2-x/(Bi)m(Bi2Te3)n. Telluride is the domain element in the reaction. The related phase equilibrium refers to the recent development. Cu/Ag-41at.%Sb eutectic alloy prepared by electroplating method was heat-treated at 300°C and 500°C for solid/solid reaction. It was found that this system will form a flat Cu2Sb layer and the Ag3Sb-Sb binary area which Sb is depleted at 300°C. The diffusion path is Cu/Cu2Sb/Ag3Sb-Sb. At 500°C, the unstable phase Cu3Sb and its decomposed phase can be observed, and also it can find that a eutectic structure which consists with Cu2Sb and Ag3Sb. The diffusion path is Cu/Cu3Sb/Cu2Sb-Ag3Sb/Ag3Sb-Sb. Sb would be the major diffusion element. The isothermal phase diagram of Ag-Cu-Sb at 300°C and 500°C were determined by the homogeneous sample annealed for 7 to 30 days. The three phase regions which are Cu-Ag-Cu78Sb20、Cu10Sb3-Cu2Sb-Ag、Ag3Sb-Cu2Sb-Sb have been observed at 300°C, and the others three phase regions which are Ag-Cu78Sb20-Cu10Sb3、Ag-Ag7Sb-Cu2Sb、Ag7Sb-Ag3Sb-Cu2Sb are established by related two phase regions. At 500°C, six three phase regions have been observed which are Ag-Cu-Liquid、Cu-Cu3Sb-Liquid、Cu3Sb-Cu2Sb-Liquid、Cu2Sb、Sb-Liquid、Ag3Sb-Ag7Sb-Liquid、Ag-Ag7Sb-Liquid. The boundary of liquid phase region is established by the tie-line in two phase regions. It is found that all the ternary solubilities in the binary compounds in the Ag-Cu-Sb system are not significant. The highest is 4.73at. % Cu in the Ag7Sb compound.

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