高溫超導線材(HTS)具有應用於MRI、NMR或磁浮列車等高磁場線圈的潛力，而目前所能製備的線材長度不足以直接使用，因此需要先發展線材接合技術，方能得到足夠的使用長度。發展零電阻超導線材接合技術可以降低接合後電流的損耗，為了達到接合後的電阻為零，需要先將線材表層的銅保護層及銀保護層去除，使線材超導層露出，以便後續的接合製程。
為了使線材超導層順利露出，需要透過蝕刻法移除線材保護層，且在蝕刻過程中需要避免影響到線材的超導性質。為了蝕刻線材銅保護層，使用30wt%氯化鐵溶液作為蝕刻劑，為了避免氯化鐵溶液影響到線材邊緣而影響到線材性質，因此在實驗中以Kapton膠帶將線材不欲蝕刻區保護，將蝕刻區域限制在需要的範圍，最終在將銅保護層蝕刻後，線材仍可保留原本60%的臨界電流。除了銅保護層外，在超導層上還殘留銀保護層，銀蝕刻液以NH4OH及H2O2以1:1比例混合，可以順利將銀層去除，且對線材臨界電流影響小。
為了確認線材在經過蝕刻及接合後的臨界電流變化，以四點量測方法測量線材V-I曲線，由於四點量測是輸出電流到線材並量測線材上特定距離(實驗中以5公分)的電壓，直到臨界電壓標準1μV/cm，而該臨界電壓所對應到的電流即臨界電流。
當線材超導層順利露出後，我們藉由機械接合法，直接以機械應力將線材超導層相互接觸在一起，使得線材接點位置僅超導層存在，不含其他材料，預期當溫度低於超導線材臨界溫度(約90K)時，接點附近電阻為零。然而實際上在接合後電阻並非為零，目前的推測是在77K時，壓力並不足以大到使線材能夠完全接觸在一起，而是會有大於超導層相干長度(0.1奈米)空隙存在，因此接合電阻不為零。

The superconductor tape length that can be prepared at present is not enough for direct application, so it is necessary to develop joining technology to obtain a sufficient length for use. The development of zero-resistance superconducting tape joining technology can reduce the current loss after joining. In order to achieve zero resistance after joining, it is necessary to remove the copper stabilizer and silver stabilizer on the surface of the tape to expose the tape superconducting layer.
In order to etch the copper stabilization layer of the strip, 30wt% ferric chloride solution was used as the copper etchant. In order to prevent the ferric chloride solution from affecting the side of the tape and affecting the properties of the tape, in the experiment, Kapton tape was used to protect the side of the tape. In addition to the copper stabilizer, there is a silver stabilizer remaining on the superconducting layer. The silver etching solution is mixed with NH4OH and H2O2 in a ratio of 1:1.In order to confirm the critical current change of the tape after etching and joining, the V-I curve of the tape was measured by the four-point measurement method.
When the superconducting layer was exposed, we used mechanical joining to directly contact the superconducting layer with mechanical stress, so that only the superconducting layer exists at the contact point of the strip without other materials.

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