Effect of CF/sub 4/ plasma pretreatment on low temperature oxides

This study describes a novel technique for forming low temperature oxides (<350/spl deg/C) using a replacement metal gate process. Low temperature oxides were generated by N/sub 2/O plasma in a PECVD system with pretreatment in CF/sub 4/. Fabricated oxides demonstrate excellent current-voltage (I-V) characteristics, such as low leakage current, high breakdown charge and good reliability. Experimental results indicate that CF/sub 4/ plasma treatment can significantly improve the mobility and resistance against hot carrier stress of MOSFETs. With excellent electrical properties, this technique is suitable for fabrication low temperature devices.