高溫超導線材(HTS)具有應用於MRI等高磁場線圈的潛力，而發展零電阻超導線材接合技術可使減少在高磁場線圈中電流損失。本研究利用金屬有機沉積法(MOD)成長YBCO薄膜作為介質接合兩超導線材並量測其薄膜磊晶性與接合後超導性質。
首先嘗試在單晶基板上使用MOD法成長單晶YBCO薄膜以尋找適當實驗參數應用於線材接合。於大氣或低氧壓環境下升溫至不同溫度持溫成長，結果發現在大氣下成長的樣品c軸方向單晶比例可隨溫度及持溫時間提升而增加，但仍無法成長c軸方向單一晶粒YBCO，推測原因為溫度提升雖使Ba,Cu液相增加而較易液相磊晶，但仍無法將所有Ba,Cu化合物熔融成液相故仍有多晶燒結區域。而低氧壓環境下成長的樣品可在790℃以上溫度將所有Ba,Cu化合物熔融成液相，高於此溫度成長的樣品能成長單一方向(103)晶粒，但與基板晶面方向(001)不符，推測是因為Ba,Cu液相與基板親合度不佳故無法從基板進行磊晶。雖然目前無法成長符合基板方向之單晶，但在低氧壓下770℃持溫樣品臨界電流密度及臨界溫度可達Jc=0.13MA/cm2及Tc=90.1K，仍有機會應用於後續接合實驗。
在進行接合前，學生架設真實超導臨界電流量測設備以分析接合前後線材超導性質。為確認量測準確性，取商用線材進行量測，結果臨界電流量測數值與公司數據相符，證實儀器精準度。接著外加磁鐵以量測超導線材在磁場下臨界電流表現，發現臨界電流隨磁場升高而降低，且與SQUID量測外加磁場下臨界電流降幅相近，證實本設備確實能精準量測在磁場下臨界電流表現。
接合線材會先蝕刻線材非超導保護層使REBCO露出，雖然仍未找到適當蝕刻液能蝕刻外層為銅之線材避免破壞超導性值。但外層為銀之線材已成功用H2O2+NH4OH蝕刻銀層及丙酸溶化Ba,Cu液相層使REBCO露出且避免破壞超導性值。而後在REBCO上鍍YBCO前驅液並與另一線材REBCO相接，在低氧壓下熱處理成長YBCO薄膜進行接合，最後成功使兩線材相連且有微弱超導電流(0.19A)可通過。

To develop zero resistance superconducting joint method without melt Ag stabilizer, we introduce metal-organic-deposit(MOD) method growing new YBCO film between two tape REBCO layer and use this film joining two tape.

Before do the joint,we try different parameter to grow YBCO film on LAO(001) substrate.Find the parameter can grow better epitaxial and superconductivity for joint experiment.The results show when holding temperature raise up can increase Ba,Cu liquid amount to get better epitaxial.And when the atmosphere change to flowing N2 can lower Ba,Cu peritectic point to get better superconductivity around 750-800℃.

We also built four-point measure system to measure tape critical current(Ic).Results show Ic value we measure is correspond with database.And Ic degrade rate under field is same as SQUID measure results.Show our measure system is accurate.

After find the proper joint parameter and built accurate measure system.We start to joint superconducting tape.First etched tape stabilizer to let REBCO layer show up without affect superconductivity.Then do the heat treatment to joint two tape.Results show we successful joint two tape with zero resistance and Ag doesn’t melt.The Ic is 0.19A.

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