捲帶與玻璃基板接合電子封裝之錯位分析

Abstract

捲帶與玻璃基板接合電子封裝之錯位分析 研究生：黃睿伸 指導教授：金大仁教授 國立交通大學機械工程研究所 中文摘要 本文研究液晶顯示器所用之驅動IC (drive IC) 以捲帶式自動接合（TAB）方式封裝時，異向導電膜（ACF）的硬化成形對捲帶所產生之溫度效應及捲帶在封裝完成後所產生的位移。TAB封裝方式為在捲帶與玻璃基板間放置一異向導電膜，然後在捲帶上加壓和加熱，使異向導電膜硬化成形，並將捲帶、異向導電膜與玻璃基板三者膠合在一起。此時捲帶上的銅導線藉由異向導電膜中的導電顆粒與具導電性的玻璃基板之ITO電極達到導電之效果。在封裝的加溫過程中，捲帶會受熱而向帶寬方向膨脹。當異向導電膜硬化成形和溫度回復常溫後，捲帶會傾向收縮回原來的形狀，若捲帶因溫度效應產生之變形量過大而使捲帶上之電極與玻璃基板之ITO電極發生錯位，則會引發短路，影響液晶顯示器的可靠度。為此，本文將利用有限單元方法研究捲帶在封裝接合時的熱傳行為和計算捲帶的變形量，探討導致捲帶發生錯位的成因，以及探討捲帶自動接合製程參數對於錯位的影響，包括IC距離遠近、捲帶熱膨脹係數、異向導電膜固化溫度等。 中文關鍵字：捲帶式自動接合；異向導電膜；有限單元法；液晶顯示器

OLB Mismatch Analysis of Tape-on-Glass Connector Student：Jui-Shen Huang Advisor：Tai-Yan Kam Institute of Mechanical Engineering National Chiao Tung University ABSTRACT This thesis is focused on the drive IC packaging of liquid crystal display monitors using the tape automated bonding (TAB) technique, and the thermal effect induced by the curing of anisotropic conductive film (ACF) on mismatch of tape-on-glass connection. In the TAB packaging process, an anisotropic conductive film is placed in between the tape and the bottom glass panel of the LCD. The whole assemblage is then cured under pressure and elevating temperature. Then the electric conduction is achieved by the connection between the copper leads and the ITO electrodes via the particles of the ACF when the curing process is complete. The tape will thermally expand in lateral direction during the heating process. When the ACF is starting to cure, it will restrain the expansion of the tape and the shrinkage of the tape. Thus there will be permanent displacement of the tape in lateral direction, and permanent residual stress will be developed in the tape and the ACF. If the permanent displacement of the tape exceeds the limit, there will be mismatches between the copper leads of the tape and the ITO electrodes. These mismatches will lead to the failure of the LCD monitors. In this thesis, we analyse the heat transfer behavior of the components of drive IC packaging and deformation of the whole assemblage during the process of tape automated bonding on glass panel by the finite element method. We then calculate the magnitude of the mismatches between copper leads and ITO electrodes and discuss the causes of mismatches. 2-D and 3-D finite element models are included in our analysis. Then we compare the theoretical and experimental results. According to the comparison, we have shown that the 3-D finite element model could produce good predictions of the deformation and the mismatches. The effects of the parameters of tape automated bonding process, including the distance from the chip to the bonding area, the thermal expansion coefficient of the tape, and the curing temperature of the ACF, on the mismatches have been considered. The thermal expansion coefficient of the tape has the most influences on the mismatches. Thus tape with appropriate CTE should be chosen to prevent from producing mismatches. Keywords：Tape Automated Bonding (TAB)；Anisotropic Conductive Film (ACF)；Finite Element Method；Liquid Crystal Display (LCD)。