本文对TFT在栅极绝缘层和非晶硅膜层沉积过程中，透明电极ITO成分对膜层的污染和TFT电学性质的影响进行分析研究。通过二次离子质谱分析和电学测试设备对样品进行分析。ITO成分会对PECVD设备、栅极绝缘层和非晶硅膜层产生污染，并会影响TFT的电学特性。建议采用独立的PECVD设备完成ITO膜层上面的栅极绝缘层和非晶硅膜层的沉积，并且对设备进行周期性清洗，可降低ITO成分的污染和提高产品的电学性能。

Indium-tin-oxide (ITO) films as transparent conductive are applied on TFT.This paper studied the influence of ITO contamination of gate insulation & a-Si layers and TFT on electrical characteristics.The obtained samples were characterized by secondary ion mass spectroscopy (SIMS) and electronic parameter measurement (EPM).The result shown on the gate insulation & a-Si layers had been contaminated by ITO in the PECVD equipment, and the contamination can make TFT electrical characteristics become worse.ITO concentration in process equipments plays an important role in the TFT electrical characteristics.Therefore, we suggest the gate insulation & a-Si layers should be deposited in independent equipment and the PECVD equipment should be cleaned periodically. Thus, the ITO contamination can be reduced and TFT electrical characteristics can also be improved.