O2气中激光烧蚀Ta2O5产物离子的氧化反应

Ta2O5薄膜作为电容元件材料的替代品已在微电子等领域中显示出广阔的应用前景1]．脉冲激光沉积（PLD）法制备Ta2O5薄膜以其显著的优点引起了广泛重视2，3]．而对激光烧蚀的物理化学过程的认识是完善这一方法的重要前提．我们曾采用时间分辨与角分辨飞行四极质谱4]和发光光谱技术5]较系统地研究了激光烧蚀Ta2O5产生的羽状物的组成和特征，并认为在O2气氛中沉积Ta2O5薄膜可以改善甚至避免形成缺氧的薄膜．但由于上述实验方法上的限制，未能详细考察激光烧蚀Ta2O5生成的离子产物在O2气氛中发生的氧化反应．为了研究激光烧蚀产物离子…

Formation of lonic Ta-containing Oxides from laser Ablation of Ta_2O_5 in Ambient O_2

The mass spectra of both positive and negative charged Ta-containing ions from laser ablatiou of Ta2O5 were measured using a time-of-flight mass spectrometer. Formation of iomc Ta-containing oxides such as TaO and TaO from Ta2O5 ablation in ambient O2 were observed for the first time. The influence of ambient O2 pressure on the intensities of ablated Ta-containing ions has also been studied. It is found that the subsequent oxidation reactions were involved in the ablation of Ta2O5 at different O2 pressure. The enthalpies of possible okidation reactions were theoretically calculated, and the possible formation reastions of the ionic Ta-contauing oxides are discussed.