ITO连接过孔电阻定量计算与设计方法  

Quantitative calculation and design method for the resistance of via hole connected by ITO

作　　者：周焱 王超 陈鹏 朱宁 江鹏 高玉杰 ZHOU Yan;WANG Chao;CHEN Peng;ZHU Ning;JIANG Peng;GAO Yu-jie(Wuhan BOE Optoelectronics Technology Co., Ltd., Wuhan 430040, China)

机构地区：[1]武汉京东方光电科技有限公司,湖北武汉430040

出　　处：《液晶与显示》2022年第1期45-55,共11页Chinese Journal of Liquid Crystals and Displays

摘　　要：TFT-LCD面板内的ITO连接过孔目前只有一些定性的设计规则,缺乏定量计算和设计过孔的方法。本文研究了此类过孔电阻的定量计算方法,同时探索了过孔电阻与击穿电流的关系,为合理设计过孔、防止过孔烧毁提供了指导依据。首先,通过分析过孔的结构,抽象出等效电阻电路图,得到多种不同结构的过孔电阻分解公式。过孔电阻主要由深孔接触电阻、浅孔接触电阻和深浅孔之间连接的ITO电阻组成。然后,通过设计不同尺寸的金属与ITO的接触过孔,使用开尔文四线检测法测量得到深孔接触电阻和浅孔接触电阻与孔尺寸之间的关系式。同时,深浅孔之间连接的ITO电阻可通过ITO方块电阻与深浅孔之间的ITO尺寸计算得到。由此,我们仅依据过孔的尺寸信息及ITO方阻数据即可计算得到各种结构的过孔电阻阻值。通过对大量过孔电阻的实测值与计算值进行相关性分析,线性相关系数达到0.96,证明了该计算方法的可靠性。最后,通过测量大量过孔的电阻阻值及其击穿电流值,发现过孔电阻阻值与击穿电流之间存在显著的幂函数关系,幂指数在-1.3附近,相关系数达到0.98。自此,建立起了一整套可定量计算和设计过孔电阻和击穿电流的方法。At present,there are only some qualitative design rules for via hole connected by ITO in TFT-LCD panel,and there is lack of quantitative calculation and design method of via hole.In this paper,the quantitative calculation method for the resistance of this kind of via hole is studied,and the relationship between the resistance and the breakdown current of via hole is explored,which provides guidance for us to design via hole reasonably to prevent the hole from burning.Firstly,by analyzing the structure of via hole,the equivalent resistance circuit diagram is abstracted and the decomposition formulas for the resistances of via holes with various structures are obtained.The resistance of via hole is mainly composed of the contact resistances of deep and shallow holes,and the resistance of ITO between the deep and shallow holes.Then,by designing the contact holes between metal and ITO in different sizes,Kelvin Four-terminal sensing method is used to measure the relationship between the contact resistances of deep and shallow holes and the hole sizes.Meanwhile,the resistance of ITO between the deep and shallow holes can be calculated by the square resistance and size of ITO between the deep and shallow holes.Therefore,we can calculate the resistance of via hole with various structures only according to the hole size and the square resistance of ITO.By analyzing the correlation between the measured and calculated resistance values of a large number of via holes,the linear correlation coefficient is 0.96,which proves the reliability of the calculation method.Finally,by measuring the resistance values and breakdown current values of a large number of via holes,a significant power function relationship between the resistance value and breakdown current is found,the power index is around-1.3,and the correlation coefficient is 0.98.Thus,we have established a set of guiding methods about resistance calculation and breakdown current evaluation of via hole quantitatively.

关 键 词：薄膜晶体管液晶显示器 氧化铟锡 过孔 接触电阻 击穿电流 

分 类 号：TN141.9[电子电信—物理电子学]