Université de Toulouse; UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, 31062 Toulouse, France.
Nanotechnology. 2010 Jul 16;21(28):285605. doi: 10.1088/0957-4484/21/28/285605. Epub 2010 Jun 28.
The controlled fabrication of Si nanocrystals embedded in thin silicon oxynitride films (<15 nm) on top of a silicon substrate has been realized by PPECVD with N(2)O-SiH(4) precursors. The effect of inert and oxidizing annealing processes on the Si nanocrystal spatial and size distributions is studied by coupling ellipsometry measurements and cross-sectional transmission electron microscopy observations. This study gives an interesting insight into the physics underlying the Si nanocrystal nucleation, growth and oxidation mechanisms. In particular, it evidences the presence in the as-deposited films of a high density of small amorphous Si particles that crystallize after high temperature thermal annealing. Annealing under oxidizing conditions is shown to be a powerful way to create tunnel oxides of good quality and controlled thickness needed to design future memory devices.
通过使用 N(2)O-SiH(4) 前体的 PPECVD，在硅衬底上的薄硅氧氮化物薄膜（<15nm）上实现了嵌入 Si 纳米晶体的控制制备。通过椭圆测量和横截面透射电子显微镜观察，研究了惰性和氧化退火过程对 Si 纳米晶体空间和尺寸分布的影响。这项研究深入了解了 Si 纳米晶成核、生长和氧化机制的物理原理。特别是，它证明了在沉积薄膜中存在高密度的小非晶态 Si 颗粒，这些颗粒在高温热退火后结晶。氧化条件下的退火被证明是一种制造高质量和受控厚度的隧道氧化物的有效方法，这是设计未来存储器件所必需的。
