液晶屏成盒后电测与亮点检出机理研究
摘要
成盒后电测是整个TFT-LCD制程中一个重要的环节。它作为对液晶屏成盒后的第一次加电检测,可以保证在进行后续工艺前对不良品进行一次筛选,避免不良品浪费后续的耗材。
本文通过研究成盒后电测信号的驱动模式,建立Switch的结构模型,并对成盒后电测与模块电测电压大小的差异分析,提出成盒后电测信号的改善方案：降低Common电压,并对其进行验证。之后重点对于Cell成盒后最主要的一大漏检——亮点进行失效模式分析,得出其可能漏检原因,提出两个改善方案：放电画面检测方案以及Gate信号修改方案,通过实际验证,确认方案的改善效果并对其进行改进。
经过产线实际确认,降低Common电压与Gate信号修改方案效果明显,前者可以提高所有不良检出率约0.2%,而后者可以提高亮点检出率0.15%,预计可带来年收益75万元。
The cell VT(Voltage Test) is an important step in the manufacturing process of TFT-LCD. As the first test after cell, through VT the NG products will be picked out and will lower the following unnecessary cost caused by the NG products.
This thesis studies the signal of VT and establishes a model for the switch. By comparing the signal of cell VT with the module ET (Electric test), we propose a method, i.e, decreasing the common voltage is put forward. Then the thesis focuses on investigation of one of the major course of the miss sorting------highlight. First the the failure mode of the highlight was analysed and then, two methods are proposed, which are, testing of the discharge unit and the other is modifying the gate signal. The improvement brought by these two methods are confirmed by on-line test. Then the methods are further improved according to the test results.
The results of on-line test shows the method of decreasing the common voltage increasing the sorting rate at about 0.2%. And the method of modifying the gate signal also increases the sorting rate at about 0.15%.
本文通过研究成盒后电测信号的驱动模式,建立Switch的结构模型,并对成盒后电测与模块电测电压大小的差异分析,提出成盒后电测信号的改善方案：降低Common电压,并对其进行验证。之后重点对于Cell成盒后最主要的一大漏检——亮点进行失效模式分析,得出其可能漏检原因,提出两个改善方案：放电画面检测方案以及Gate信号修改方案,通过实际验证,确认方案的改善效果并对其进行改进。
经过产线实际确认,降低Common电压与Gate信号修改方案效果明显,前者可以提高所有不良检出率约0.2%,而后者可以提高亮点检出率0.15%,预计可带来年收益75万元。
The cell VT(Voltage Test) is an important step in the manufacturing process of TFT-LCD. As the first test after cell, through VT the NG products will be picked out and will lower the following unnecessary cost caused by the NG products.
This thesis studies the signal of VT and establishes a model for the switch. By comparing the signal of cell VT with the module ET (Electric test), we propose a method, i.e, decreasing the common voltage is put forward. Then the thesis focuses on investigation of one of the major course of the miss sorting------highlight. First the the failure mode of the highlight was analysed and then, two methods are proposed, which are, testing of the discharge unit and the other is modifying the gate signal. The improvement brought by these two methods are confirmed by on-line test. Then the methods are further improved according to the test results.
The results of on-line test shows the method of decreasing the common voltage increasing the sorting rate at about 0.2%. And the method of modifying the gate signal also increases the sorting rate at about 0.15%.
引文
[1]Method of manufacturing thin film transistors, Biing-Seng Wu, US Patent 5,721,164,1998
[2]Very-Low-Voltage Testing of Amorphous Silicon TFT Circuits, Taichung, 2009 Asian Test Symposium
[3]TFT-LCD technology, M. Katayama, Thin Solid Films Volume 341, Issues 1-2,12 March 1999, Pages 140-147
[4]液晶显示技术.刘永智,杨开恩.电子科技大学出版社.2000.291-299.
[5]平板显示技术.应根裕,胡文波,邱勇.人民邮电出版沈.2003.1-10.
[6]液晶显示技术综述,周艳琼,影像技术,2002
[7]平板显示技术的新进展,谢智波,电视技术,2007
[8]Lot release times and dispatching rule for a TFT-LCD cell process, J. T. Lina F. K. Wangb, Robotics and Computer-Integrated Manufacturing, Volume 24, Issue 2, April 2008, Pages 228-238
[9]TFT-LCD面板的驱动与设计.戴亚翔.五南图书出版社.2006.4
[10]STN—CD显示驱动技术,郭振东,电子器件,2001
[11]Design of Medium Size Digital TFT-LCD Test Device Based on FPGA, HONG Jun-jie, WU Gui-xing, HUANG Xian-fu, WU Yu-liang, 《Chinese Journal of Liquid Crystals and Displays》 2009-02
[12]Deriving Pixel Charging Ratio Equation, Jason Huang, October 14,2007
[13]Display technologies for portable communication devices, Kimmel, J. Hautanen, J.; Levola, T., Proceedings of the IEEE, Volume:90 Issue:4
[14]Scan driver of LCD with fault detection and correction function, BW Wang, US Patent 6,467,057,2002
[15]Optical charge-sensing method for testing and characterizing thin-film transistor arrays, Kido, T.; Kishi, N.; Takahashi, H., Selected Topics in Quantum Ele, Volume:1 Issue:4
[16]High-speed TFT LCD defect-detection system with genetic algorithm, Chern-Sheng Lin, Yo-Chang Liao, Kun-Chen Lee, Mau-Shiun Yeh, Assembly Automation
[2]Very-Low-Voltage Testing of Amorphous Silicon TFT Circuits, Taichung, 2009 Asian Test Symposium
[3]TFT-LCD technology, M. Katayama, Thin Solid Films Volume 341, Issues 1-2,12 March 1999, Pages 140-147
[4]液晶显示技术.刘永智,杨开恩.电子科技大学出版社.2000.291-299.
[5]平板显示技术.应根裕,胡文波,邱勇.人民邮电出版沈.2003.1-10.
[6]液晶显示技术综述,周艳琼,影像技术,2002
[7]平板显示技术的新进展,谢智波,电视技术,2007
[8]Lot release times and dispatching rule for a TFT-LCD cell process, J. T. Lina F. K. Wangb, Robotics and Computer-Integrated Manufacturing, Volume 24, Issue 2, April 2008, Pages 228-238
[9]TFT-LCD面板的驱动与设计.戴亚翔.五南图书出版社.2006.4
[10]STN—CD显示驱动技术,郭振东,电子器件,2001
[11]Design of Medium Size Digital TFT-LCD Test Device Based on FPGA, HONG Jun-jie, WU Gui-xing, HUANG Xian-fu, WU Yu-liang, 《Chinese Journal of Liquid Crystals and Displays》 2009-02
[12]Deriving Pixel Charging Ratio Equation, Jason Huang, October 14,2007
[13]Display technologies for portable communication devices, Kimmel, J. Hautanen, J.; Levola, T., Proceedings of the IEEE, Volume:90 Issue:4
[14]Scan driver of LCD with fault detection and correction function, BW Wang, US Patent 6,467,057,2002
[15]Optical charge-sensing method for testing and characterizing thin-film transistor arrays, Kido, T.; Kishi, N.; Takahashi, H., Selected Topics in Quantum Ele, Volume:1 Issue:4
[16]High-speed TFT LCD defect-detection system with genetic algorithm, Chern-Sheng Lin, Yo-Chang Liao, Kun-Chen Lee, Mau-Shiun Yeh, Assembly Automation