FeSe1-x於還原保護性氣氛中(Ar+3 %H2)進行製備，並且於400 °C進行燒結製備正方晶系之超導β相氧化鉛結構(PbO structure)，其研究顯示幾乎為純超導β相。然而樣品在高溫(>700 °C)進行燒結後，會有相當之非超導β相存在，須過量Fe才能低溫退火純化超導相，而M-T測量顯示燒結製程超導β相之超導轉換溫度(Tc)約8.4 K。
　　摻雜不同比例之硫元素含量會造成其他非超導相之生成，亦需在富鐵含量比例下，才能生成較純之超導β相；在保持主要超導β相下，進行不同摻雜硫比例進行分析，隨著摻雜硫含量越多，其ab平面收縮，c軸壓縮，整體體積逐漸下降。當比例為Fe(Se0.85S0.15)0.85時，具有最高之超導轉換溫度約9.0 K。
　　利用錫化硒(SeSn)作為助熔劑於鋁酸鑭(LaAlO3,LAO)基板進行液相之硒化鐵(FeSe1-x)厚膜生長。厚膜於溫度910-800C從含有錫元素之液相中成長獲得純化之β相。EBSD顯示具有超導β相且有高結晶性，然而超導轉換溫度約6.0 K。由FeSe-SeSn相圖可得知高達5 %的SeSn固溶於FeSe之中，但藉由雷射剝蝕感應偶合電漿質譜儀(Laser Ablation-Inductively Coupled Plasma Mass Spectroscopy,LA-ICP-MS)進行分析，可以得知Sn含量約為4 ppm，並未進行摻雜，說明Sn於成長過程中進行揮發，產生過飽合度促進晶體成長。利用其他助熔劑(KCl)，於高溫下進行晶體成長，轉換溫度約為7.5 K；不同助熔劑之高溫晶體成長之超導轉換溫度皆下降。比較厚膜與固相燒結之Fe2p3/2能峰可以發現，若鐵之平均價態較低，會具有較低之超導轉換溫度。

　　FeSe1-X(1-X=0.97) was prepared by solid state synthesis in reduction(Ar+3%H2)atmosphere. The samples sintered at 400°C were of the tetragonal PbO structure (β phase), showing little trace ofδ phase (hexagonal). However, the samples sintered at higher temperatures contained a fair amount of δ phase,and extra iron was required to react with  phase resulting in pure β phase with remaining Fe.β FeSe1-x showed the superconducting trasition temperature(Tc) of 8.4 K by M-T analysis.
　　Sulfur substitution has influence on the sintering process of pure β phase.To reduce δ phase,the composition also requires extra iron.We found that the a and c axes were as well as the volume reduced as the increase of sulfur doping.Tc was found to increase with sulfur doping .The highest superconducting onset was at about 9.0 K for the sample Fe(Se0.85S0.15)0.85.
　　Thick films of FeSe1-X were grown on LaAlO3 single crystal substrates by liquid phase processing with SeSn as the flux. The thick films grown around 910-800°C had pure β phase.Electron Backscatter Diffraction(EBSD) confirmed the films to have tetragonal β-phase with high crystallinity. The films were superconducting but with lower Tc of 6.1 K.
　　Although the phase diagram showed some solid solubility of SeSn in FeSe, Laser Ablation-Inductively Coupled Plasma Mass Spectroscopy(LA-ICP-MS) showed that there was only about 4ppm of Sn in the film. It’s suspected that tin was vaporized during growth. The evaporation of Sn also created the supersaturation for growth of FeSe from the Liquid phase.
　　Besides,we alse used KCl as the flux to grow crystal and the obtained crystals showed slightly higher Tc of 7.5 K.Nevertheless, the Tc was still lower than that for the powder samples. X-ray photoelectron spectroscopy showed that there was a lower average Fe valence for the thick films, which was probably the cause for lower Tc observed in thick films.

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