OTFT开关比对有源层厚度、杂质浓度间制约关系的影响研究

本文从物理角度推导并分析Brown方程的本质,并将之用于OTFT开关比的分析。首次通过引入关键参数K(杂质层电流/感应层电流)对OTFT开关比进行了分析,获得OTFT中有源层厚度和杂质浓度潜在的、可被允许的上限值。在此前提下,重点分析了有源层厚度、有效杂质浓度对OTFT开关比的影响。接着根据模拟分析的结果,提出一种有效且简易的判断OTFT是否逼近开关比极限的方法,并分别论证在逼近/远离开关比极限的情况下,降低NA和dS对开关比提升的有效性,及不同情况的OTFT应采取的优化措施。最后,文中给出了一定开关比约束下有效掺杂浓度/有源层厚度的临界关系曲线,它具有重要的实用意义,且进一步约束了OTFT中有源层厚度和有效杂质浓度的所允许的上限值。

Relationship between NA and dS Restricted by Ion/Ioff for OTFT

The functions of Brown model for ideal OTFT were analyzed physically in this paper, which further was used to analyze Ion/loft by numeral simulation method. Firstly, the ratio of impurity current/induction current （K） was analyzed, and the maximum permissible value for Na and ds were obtained. Under the premise of max NA and ds, the relationship of Ion/loft with NA and ds was then analyzed, and the effect of deceasing NA and ds to improved Ion/Ioff was demonstrated. Base on the analysis, one method was further put forward to judge where OTFT approximate to its ultra value of Ion/Ioff, according to which the corresponding optimization measure can be advised. At last, the relationship curve of Na with ds was qualitatively plotted under the restriction by the ratio of Ion/loft, it was of great significance, and further decreased the ＂maximum permissible value＂ of Na and ds that restricted by K curve.