Structural and electrical properties of sol–gel derived Ge nanocrystals in SiO2 films
Structural and electrical properties of sol–gel derived Ge nanocrystals in SiO2 films
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DOI：
10.1007/s00339-010-6156-4
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发表时间：
2011-04
期刊：
影响因子：
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通讯作者：
S. Knebel;A. Kyriakidou;H. Bracht;H. Rösner;G. Wilde
中科院分区：
文献类型：
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作者：
S. Knebel;A. Kyriakidou;H. Bracht;H. Rösner;G. Wilde
采用溶胶-凝胶法在掺硼硅衬底上制备了化学计量比的锗硅酸盐混合玻璃薄膜。为了引发元素锗（Ge）纳米晶体的生长，将玻璃膜在合成气体中在600至1000°C的温度下退火。高分辨率和传统的透射电子显微镜表明，嵌入在玻璃膜中的Ge纳米晶体的形状和尺寸的强烈影响的退火条件。能量色散X射线分析表明，锗偏析在界面处的硅衬底和蒸发的自由表面。这导致接近Si衬底和SiO2表面的Ge纳米颗粒的洁净区。电容-电压测量的金属氧化物半导体结构与Ge颗粒和不展示的薄层结构的电荷存储特性。我们确定了明确的趋势，在纳米粒子的电性能作为退火条件的函数，并观察陷阱电荷和粒子密度之间的相关性。
Stoichiometric mixed germanate–silicate glass films were fabricated on boron-doped silicon substrates by means of a sol–gel based synthesis procedure. In order to initiate the growth of elemental germanium (Ge) nanocrystals, the glass films were annealed in forming gas at temperatures between 600 and 1000°C. High-resolution and conventional transmission electron microscopy show that the shape and size of Ge nanocrystals embedded in the glass film are strongly influenced by the annealing conditions. Energy-dispersive X-ray analysis reveals that Ge segregates at the interface to the silicon substrate and evaporates from the free surface. This leads to a denuded zone of Ge nanoparticles close to the Si substrate and the SiO2surface. Capacitance–voltage measurements of a metal–oxide–semiconductor structure with and without Ge particles demonstrate the charge-storage characteristic of the thin-layer structure. We identify clear trends in the electrical properties of the nanoparticles as a function of the annealing conditions and observe correlations between trapped charge and particle density.