We investigated the formation mechanism of interfacially mixed AlSiO_x films on Si surfaces under low-energy (<15 eV), high-flux (>4 × 10¹⁵ cm⁻² s⁻¹) O₂⁺ ion bombardment during Al₂O₃ plasma-enhanced atomic layer deposition. When high-dose O₂⁺ ions (>1 × 10¹⁷ cm⁻² cycle⁻¹) were incident on the growing film surface during the oxidation steps in Al₂O₃ atomic layer deposition (ALD), interfacially mixed films with thin (∼0.8 nm) SiO_x interlayers were formed on Si surfaces. The deposited films possessed a layered structure of Al₂O₃/AlSiO_x/AlO_x layers. In order to reveal the formation mechanism, films deposited during the early stages of ALD were evaluated using an angle-resolved x-ray photoelectron spectroscope. In the first oxidation step, thin, low-density SiO_x films with weak Si–O bonds containing excess oxygen were formed on the Si surface. In subsequent oxidation steps, adsorbed Al atoms on the surface were knocked on by the energetic ions and penetrated into the SiO_x film. As a result, Al atoms were taken into SiO_x. Some of the Al atoms accumulated near the interface. After several tens of cycles, ordinary Al₂O₃ films were deposited on the Si-rich layers. Thus, the films with a layered structure of Al₂O₃/AlSiO_x/AlO_x layers were formed on the Si substrate.

中文翻译：

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Al2O3等离子体增强原子层沉积过程中低能高通量离子轰击引起的界面混合

我们研究了在Al ₂ O ₃的低能（<15 eV），高通量（> 4×10 ¹⁵  cm ^-2  s ^-1）O ₂ ⁺离子轰击下Si表面界面混合AlSiO _x膜的形成机理等离子体增强的原子层沉积。在Al ₂ O ₃原子层沉积（ALD）的氧化步骤中，当高剂量的O ₂ ⁺离子（> 1×10 ¹⁷  cm ^-2 循环^-1）入射到生长的薄膜表面时，界面混合的薄膜很薄（约0.8 nm）SiO _x在Si表面上形成中间层。沉积的膜具有Al ₂ O ₃ / AlSiO _x / AlO _x层的层状结构。为了揭示形成机理，使用角度分辨X射线光电子能谱仪评估了在ALD早期阶段沉积的膜。在第一个氧化步骤中，在硅表面上形成了一层薄而低密度的SiO _x薄膜，这些薄膜具有含有过量氧的弱Si-O键。在随后的氧化步骤中，表面上吸附的Al原子被高能离子撞击，并渗透到SiO _x膜中。结果，Al原子被带入SiO _x。一些Al原子聚集在界面附近。几十个循环后，普通的Al ₂ O ₃膜沉积在富Si层上。因此，在Si衬底上形成具有Al ₂ O ₃ / AlSiO _x / AlO _x层的层状结构的膜。