臺灣博碩士論文加值系統

本實驗利用高溫爐燒熔氧化鎂基片上的Y1Ba2Cu3O7-x 粉末製作超導
厚 膜 ( 基片的大小為3mm×7mm )。由於在高溫時基片會有擴散的現
象 , 影 響到超導臨界溫度 , 所以先測試燒熔的溫度 , 找出在燒熔的
最低爐溫下擴 散現像最小的條件 , 範圍1020oC到1035 oC之間 , 每5
oC測試一次 , 補氧 之後做超導臨界溫度的測量 , 結果發現1020 oC的燒
熔條件最好。另外也在 相同的條件下 , 取基片上有鍍一層Y1Ba2Cu3O7-x
薄膜的基片 , 再塗上粉末 來燒熔 , 做一翻比較 , 結果發現後者的臨界
溫度較前者好。 因為實驗的目的是以表面無鍍薄膜的基片做為
主要燒熔條件 , 在純 123相燒熔過程中 , 臨界溫度無法提高 , 因
此加入211相的粉末 , 依照成 分比例30%、40%和50%做燒熔的測試 ,
藉由40%燒熔條件較好的一組 , 再做相同條件下30%和50%燒熔樣品
的測試 , 經過臨界溫度的測試 , 發現 30%這一組的樣品臨界溫度較
沒有加入211相提高最多。 最後 , 對30%、40%和50%三種比例的
樣品 , 通入1mA和100mA的 電流 , 量取樣品電阻與溫度下的關係 ,
發現30%的電流密度量測較好。

The experiment used high temperature oven to melt Y1Ba2Cu3
O7-x powder on MgO substrate to produce superconducting thick
film . ( The substrate size was 3mm×7mm. ) . However in high
temperature , there was diffusion problem which affected the
critical temperature Tc of the superconducting film. In order to
find out the melting temperature which caused less diffusion
problem , we used oven temperature from 1020oC to 1035 oC in
five degree interval. After annealing with oxygen , we measured
the superconducting critical temperature Tc . We found that the
best melting condition is 1020 oC . Under the same melting
conditions , if we used MgO substrates with buffer layers of Y1
Ba2Cu3O7-x , the critical temperature Tc of the thick film
could become larger. Since the critical temperature was not
very well for both cases . We added 30%、40% and 50% in weight
of Y2Ba1Cu1O7-x powder to the pure 123 phae powder.After the
critical temperature measurements , we found the sample with 30%
211 phase added was the best . Finally , we let 1mA and
100mA current passing through these samples with 30%、40% and
50% 211 phase added and measured their resistance as a function
of temperature . We found that the current density of the 30%
211 phase added sample was the best .