三氯乙烯氧化硅膜推迟破坏性击穿的机理研究

MECHANISM FOR THE DELAY OF DESTRUCTIVE BREAKDOWN IN TCE OXIDE FILMS

本文对三氯乙烯(TCE)氧化推迟SiO_2膜的破坏性击穿及其机理进行了研究。结果表明,随着TCE流量的增大、处理时间的增加、温度的升高和氧分压的降低,SiO_2膜的击穿电流耐量增大。但过大的TCE流量和过长的处理时间,将使击穿特性变坏。结果还表明,击穿电流耐量的增大与膜内电子陷阱密度的增大有关。文中提出包括三种恶性循环在内的“低势垒点-电场增强”击穿模型,并考虑氧化气氛中的H_2O对击穿特性的影响,引入电子陷阱抑制低势垒点-电场增强的作用,分析TCE氧化推迟破坏性击穿的机理。

This paper study the delay of destructive breakdown and its mechanism on SiO2 films by TCE treatment. The result show that the breakdown current capacity increase with increasing the TCE flow-rate, treatment time and temperature, and reducing the oxygen partial pressure. However, excessive quantity of the TCE flow-rate and prolonging of treatment time make the breakdown characteristics degradation begin to appear. The results also indicate, the increment of breakdown current capacity is associate with the increment of density of electron trap in SiO2 films. In this paper, we propose a breakdown model of 'low barrier point-electrical field enhanced' which involve three processes of mutual reinforcement, and consider for the first time the effect of H2O in TCE oxidation on the breakdown characteristics. The restrained function of electron trap on electrical field enhanced in low barrier point is quoted, and analyze the mechanism for delay of destructive breakdown in TCE oxides.