含氟超薄栅氧化层的抗击穿特性研究

A Study on Breakdown Characteristics in Fluorinated Ultra-Thin Gate Oxide

对含 F超薄栅氧化层的击穿特性进行了实验研究。实验结果表明 ,在栅介质中引入适量的 F可以明显地提高栅介质的抗击穿能力。分析研究表明 ,栅氧化层的击穿主要是由于正电荷的积累造成的 ,F的引入可以对 Si/Si O2 界面和 Si O2 中的 O3 ≡ Si·与 Si3 ≡ Si·等由工艺引入的氧化物陷阱和界面陷阱进行补偿 ,从而减少了初始固定正电荷和 Si/Si O2 界面态 ,提高了栅氧化层的质量。研究结果表明 ,器件的击穿电压与氧化层面积有一定的依赖关系 ,随着栅氧化层面积的减小 ,器件的击穿电压增大。

The breakdown characteristics in fluorinated ultra-thin gate oxide have been investigated. Experimental data show that F ions introduced into thermal SiO 2 oxide can improve the breakdown characteristics of thin gate oxide. And F ions can decrease oxide charges and interface states induced by process. The breakdown voltage of the device, which increases with the decrease of gate area, is strongly dependent on the area of gate oxide.