本研究利用化學及柱狀缺陷對YBaCuO超導體之臨界電流密度提升之特性，利用化學氣相沉積法(CVD)長氧化鋅奈米柱於YBaCuO粉體做為前驅物，摻雜於YBaCuO後長完單晶以期得到高臨界電流，並與摻入市售氧化鋅奈米顆粒與次微米顆粒做比較。換言之，我們利用一維的氧化鋅奈米柱取代零維的氧化鋅奈米顆粒以獲得更高的化學及柱狀缺陷。並逐一探討不同實驗參數如持溫時間、氧氣濃度等對於氧化鋅沉積於超導粉體形貌的影響。
CVD實驗於適當製程溫度與氣體通量下，長在Y211的奈米柱徑約為50nm，長約為1μm，長寬比約為15至20。而後將含有氧化鋅奈米柱之Y211粉末送ICP-MS分析鋅，得知在粉末中濃度約在2~5wt%間，並依此結果做為摻入成長YBaCuO單晶之鋅含量定量依據。在77K添加適量氧化鋅下，由Jc-H可得奈米柱的零場Jc值約為55,000 A/cm2，高於奈米顆粒的40,000 A/cm2，也高於次微米顆粒的25,000 A/cm2，更高於標準樣品(未添加)的18,000 A/cm2。在Fp部分，0.1wt%的奈米顆粒最高為16 kT•A/cm2，而奈米柱最高為35 kT•A/cm2，與文獻添加Pt樣品的最高值23 kT•A/cm2相比，我們的Fp高於文獻值。根據scaling law，添加氧化鋅會使整體趨向Dk pinning(因外加磁場增加造成的釘札)，而添加奈米柱更往此趨勢與Normal pinning(零場下的釘札)移動。

In the study chemical and columnar defects can increase Jc of the YBaCuO superconductor. By chemical vapor deposition ZnO nanorods are growing on YBaCuO powder as precursor to dope in YBaCuO superconductor for single grain growth to obtain high Jc. And compare superconductivity with commercial ZnO nano and sub-micro particles. In other words, 1-Dimension columnar defects can be considered as stronger pinning centers than 0-dimension ones. And investigate the influence parameters such as holding time, oxygen concentration on the shape of ZnO.
The aspect ratio of ZnO nanorods growing on Y211 is c.a. 15 to 20 as CVD procedure under proper temperature and gas flow. The length of each nanorod is c.a. 1μm, 50nm width. The Zn concentration of the precursors is around 2~5 wt% by ICP-MS, which is the quantitative results for these precursors doping in YBaCuO. Under 0 field, at 77K and properly ZnO doping, the Jc of nanordos(NR) is c.a. 55,000 A/cm2, higher than nanoparticles’(NP) 40,000 A/cm2 and sub-micro particles’(MP) 25,000 A/cm2, the lowest Jc is Zn free standard, 18,000 A/cm2. For pinning force, the Fp of NR is 35 kT•A/cm2, NP is 16 kT•A/cm2. Comparing with our results and 23 kT•A/cm2 Gruss’s with extra Pt doping, our results had better performance than the references. Base on the scaling law, doping ZnO can shift to Dk pinning, moreover, the nanorods would shift to normal and Dk pinning.

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