Charging damage in dual gate oxide process

Plasma charging damage in a dual gate oxide 0.25/spl mu/m technology was investigated. Charging damage was identified in IMD HDP deposition and VIA process. It was found in this paper that a thick gate oxide device always shows better or equal plasma charging resistance, despite the fact that the thick gate oxide has suffered quality degradation by two-step growth. On the other hand, it is clearly demonstrated in our experiments that the dependence of charging damage on gate oxide thickness is plasma source dependent, which is in good agreement with the previous predictions by K. P Chueng [P2ID 1998, p34].