【作者】 岳丽；

【导师】 邓文；

【作者基本信息】 广西大学 ， 理论物理， 2006， 硕士

【摘要】 在当今的微电子工业中，二氧化硅由于其有着良好的可制造性、极好热稳定性、抗湿性而成为晶体管中的栅极电介质和电容电介质的首选材料。随着电子器件的微型化，二氧化硅层越来越薄，二氧化硅层将存在较多的缺陷，通过电介质的漏电现象逐渐增加。要提高器件的稳定性，必须减少二氧化硅层中的缺陷，提高二氧化硅层的质量。目前，对硅基半导体中SiO₂／Si的结构、形成、缺陷等基本问题仍然很不了解。我们采用一种新的分析硅基半导体中缺陷的技术——正电子湮没谱（PAS）技术来研究SiO₂／Si界面行为。 本文的主要研究内容如下： 1．用双探头符合多普勒展宽技术测量了热氧化法生长的四种不同厚度SiO₂膜的SiO₂-Si样品及SiO₂晶体的商谱。实验结果表明：硅基上氧化膜越厚，氧含量越高，其商谱的氧信号峰越高；硅基上氧化膜越薄，缺陷就越多。 2．用单能慢正电子技术测量四种不同厚度SiO₂膜的SiO₂-Si样品和SiO₂晶体的正电子湮没辐射Doppler展宽谱，作出了S参数和W参数与正电子注入能量和注入深度的关系曲线，从而研究SiO₂-Si界面结构和缺陷。SiO₂-Si体系可以看成由表面层，SiO₂层，SiO₂-Si界面层，以及半无限大的Si基体这几部分组成．SiO₂-Si样品的近表面层（其厚度约为1.5nm）和SiO₂晶体近表面层的结构几乎相同，具有比较完整晶体结构的薄SiO₂层，表面存在一些缺陷。SiO₂和Si基体之间存在过更多还原

【Abstract】 In the present-day, micro-electronic industry is dominated by silicon-based devices. Because SiO₂ has many good qualities such as easy-fabricated, best hot stability, higher wet-resistance, it becomes the preferred material for grid dielectric and capacitor dielectric in the transistor. With the ever-continuing drive toward miniaturization, the layer of SiO₂ becomes more and more thin. Then, more defects will come forth in the layer of SiO₂. More defects lead the electric current leakage phenomenon to increase gradually. To enhance the electrical performance of the electron devices, we must reduce defects in SiO₂ layer and raise the quantity of the layer. At present, fundamental questions about the formation, evolution, and defects in SiO_/Si interface remain not fully understood. Here, we examine the value of a newly emerging technique for analyzing defects in silicon-based systems, positron annihilation spectroscopy （PAS）. The main contents of this work were as follows:Firstly, four SiO₂-Si samples with deferent thickness of layers and quartz SiO₂ have been measured by two-detector coincidence system of Doppler broadening of positron annihilation radiation. The ratio curves illustrate that the sample with thicker silicon oxide layer has higher oxygen contents and a更多还原