薄热氮氧化硅介质膜中的电流传导机构

CURRENT TRANSPORT MECHENISM IN THERMAL-LYNITRIDED SiO_2 THIN FILMS

本文回顾了半导体介质膜中几种主要导电机构。提出了陷阶辅助二步隧穿模型来描述深度氮氧化膜SiO_xN_y的电导特性,而浅度氮氧化膜的电导则可用增强Fowler-Nordheim隧穿来描述。根据模型计算的理论曲线和实验结果符合得很好,决定二步隧穿过程的主要参数φ_t和N_t在2.46—2.56eV和1.2×10^(19)—7.2×10^(20)cm^(-3)范围内。这些结果和前人实验结果相一致,并从俄歇分析结果得到满意解释。上述二步隧穿模型同样适用于MNOS结构或含有陷阶的其他介质MIS结构的电导过程。

A new trap-assisted two-step tunneling model is proposed to explain the conduction enhancement characteristics and conduction mechanism in heavily-nitrided oxide films. A theoretical calculation is carried out to fit the theory to the experimental results. The trap density and trap energy level are found to be in the range of 1.2× 10(19)-7.2×10(20)cm- and 2.46-2.56 eV respectively. These results agree satisfactorily with the Auger spectroscopic data. Furthermore, this model can also be applieci p MNOS structure or MIS devices with other traps.