摘要
高开口率高级超维场转换技术(HADS)阵列基板沟道干法刻蚀后,源/漏电极线边缘易形成光刻胶残留,导致钝化层微裂纹和沟道污染。为改善光刻胶残留和薄膜晶体管(TFT)漏电流,研究了光刻胶变性残留形成机理,光刻胶灰化工艺对光刻胶缺口形貌影响,解释了不同灰化时间下光刻胶缺口、台阶和TFT漏电流关系。采用全因子实验设计,研究了后处理工艺对漏电流影响。结果表明,在增强型电容耦合等离子体刻蚀中形成光刻胶缺口和副产物,两者共同作用导致光刻胶变性残留。光刻胶灰化工艺提高偏置功率,降低压力,使光刻胶覆盖源/漏极距离d>0,光刻胶缺口显著改善。然而随着距离d增加,沟道台阶增长,导致TFT漏电流增加。后处理优化进一步减少沟道副产物污染,降低背沟道漏电流。当后处理偏置功率1 kW,压力4 Pa,O_(2)/SF_(6) 10时,高温光照漏电流较量产条件降低18%,且无光刻胶残留发生。该工作为不同模式的沟道干法刻蚀工艺研究、光刻胶形貌优化和TFT漏电流改善提供参考。
After channel dry etching of High Aperture Advanced Super Dimensional Switching(HADS)array substrate,the edge of source/drain electrode line was prone to form Photo Resist(PR)remain,leading to passivation microcracks and channel contamination.In order to improve PR remain and TFT leakage current,the formation mechanism of PR remain and effect of PR ashing process on PR undercut were studied.Then,the relationship between PR undercut,channel tail and TFT leak-age current at different ashing time was explained.Effect of post-treatment on TFT leakage current was studied by a full factor experiment.The results showed that PR undercut and by-product were formed in enhanced capacitive coupled plasma etching,which together caused PR remain.PR under-cut was significantly improved by increasing bias power and reducing pressure in PR ashing process,with PR coverage source/drain distance d>0.But as the distance d increased,the channel tail grew,causing an increase of TFT leakage current.Post-treatment optimization further reduced channel con-tamination to reduce back-channel leakage current.With post-treatment of bias power 1 kW,pressure 4 Pa,O_(2)/SF_(6) 10,the leakage current was reduced by 18%compared to the mass production,and no PR remain occurred.This work could provide a reference for process research,PR morphology opti-mization and TFT leakage current improvement in different modes of channel dry etching.
作者
杨小飞
孟佳
苏磊
李洋
万稳
吕耀军
王军才
邓金阳
YANG Xiaofei;MENG Jia;SU Lei;LI Yang;WAN Wen;LYU Yaojun;WANG Juncai;DENG Jinyang(Chengdu BOE Optoelectronics Technology Co.,Ltd.,Chengdu 611731,CHN)
出处
《光电子技术》
2024年第4期328-333,344,共7页
Optoelectronic Technology
