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利用光发射谱和Langmuir探针对热阴极直流放电等离子体化学气相淀积(PCVD)金刚石薄膜的等离子体环境进行了原位诊断 ,根据探针和光谱诊断结果定量地计算了在放电电流密度变化过程中基态氢原子和基态CH基团数密度的变化 ,发现基态和激发态的原子氢和CH基团的数密度均因放电密度增加而提高 .电子密度、CH发射的相对强度均随放电电流密度的增加而线性增加 ,而不同的含碳活性粒子的产生与电子温度的升高有关 .将诊断结果与金刚石的生长相联系 ,表明激发态的原子氢的产生促进了金刚石的生长 ,等离子体环境中电子温度和密度的增加对金刚石生长速率提高起着重要的作用 . 相似文献
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EFFECT OF THERMAL TREATMENTS ON THE SUPERCONDUCTIVITY OF UNDOPED AND WO3 DOPED Y-Ba-Cu-O SYSTEM 下载免费PDF全文
Undoped and WO3-doped Y-Ba-Cu-O ceramics have been slowly cooled in flowing oxygen or quenched in air from 900℃ to room temperature, after sintering at 900℃ for 3Oh in flowing oxygen. The ac susceptibility measurements show that the Tc of the quenched WO3-doped Y-Ba-Gu-O superconductor can reach 88K, while the undoped Y-Ba-Cu-O ceramic quenched in air is a non-superconductor. X-ray diffraction data show that WO3 does not enter into the YBa2Cu3O7-x lattice but forms all impurity phase. The WO3-doped YBCO specimens quenched in air consist of orthorhombic YBa2Cu3O7-x phase and an impurity phase which increases with increasing WO3 content. Raman spectra chow that oxygen contents are different for undoped and WO3-doped samples. It la suggested that suitable doping with WO3 can change the oxygen content and reduce the effect of thermal treatments on the superconductivity of Y-Ba-Cu-O system. 相似文献