The synthesis of high temperature superconducting films of Y: 247 (T_c approx 73 K) have been successfully achieved. The difficulty in synthesis owing to narrow range of stability of Y: 247 has been taken care of through several quenching modes, e.g. quenching of the films synthesized at approx 850deg C, in air or in liquid nitrogen. The energy dispersive analysis of X-rays (EDAX) and transmission electron microscopy (TEM) studies of the as processed film, Y_2Ba_4Cu_7O(14+x), exhibit nearly correct cationic stoichiometry of 2:4:7; also narrow regions (< 50 A) of minority Y: 124 phase and stacking faults capable of working as flux pinning sites have been invariably found to be present. In addition to Y: 247, Ag admixed films have also been investigated. The T_c here is approx 70-75 K which is similar to that of the film without silver. Representative estimates of transport critical current density (J_c) for Y: 247 films is approx 10~3 A/cm~2, and with silver corresponding to Y_2Ba_4Cu_7O(14+x)(Ag_(0.1)) is found to be approx 10~4 A/cm~2.
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机译：Y：247（T_c约73 K）的高温超导薄膜的合成已成功完成。由于Y：247的窄范围稳定性，合成困难已通过几种淬灭方式，例如H 2 O 3来解决。在空气或液氮中在约850摄氏度下淬火合成的薄膜。加工后的薄膜Y_2Ba_4Cu_7O（14 + x）的X射线能谱分析（EDAX）和透射电子显微镜（TEM）研究表明，阳离子化学计量比几乎是正确的2：4：7;此外，还总是发现存在少数Y：124相的狭窄区域（<50 A）和能够用作磁通钉扎位点的堆垛层错。除Y：247外，还研究了Ag混合膜。这里的T_c约为70-75K，这与没有银的薄膜的T_c相似。 Y：247薄膜的传输临界电流密度（J_c）的代表性估计约为10〜3 A / cm〜2，并且对应于Y_2Ba_4Cu_7O（14 + x）（Ag_（0.1））的银约为10〜 4 A / cm〜2。
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