利用脉冲激光沉积法在真空条件下生长的氧化物薄膜通常存在氧元素缺失现象.在以往研究中,上述氧元素缺失的原因被归结于等离子体中较轻的氧离子更易被散射或薄膜中的氧元素更易被高能量等离子体再溅射等.本文提出了真空下脉冲激光沉积氧化物薄膜中造成氧元素缺失的另一个可能原因:由于等离子体中O+离子到达衬底的时间早于金属离子,较早到达的氧元素不能单独在衬底上以固体形式沉积,从而造成薄膜氧元素的缺失.当使用波长为248 nm的脉冲激光时,O+离子通过三光子过程大量产生,证实了上述原因. The oxide films grown under vacuum by pulsed laser deposition often suffer from the absence of oxygen, a factor that has been attributed to the lighter oxygen ions in the plasma being more easily scattered or to Oxygen is more likely to be re-sputtered by high-energy plasma, etc. Another possible reason why the oxygen vacancies are caused by the pulsed laser deposition of oxide thin films under vacuum is presented in this paper: Since the O + ions in the plasma reach the substrate earlier than the metal ions , The earlier arrival of oxygen can not be deposited as a solid on the substrate alone, resulting in the absence of oxygen in the film.O + ions are mass-produced by the three-photon process when pulsed laser light having a wavelength of 248 nm is used, confirming the above reasons .