Surface treatment validation of inorganic BARC on 0.25 mu m Non Volatile Memory technology

For 0.25 mu m Non Volatile Technology (NVM) we developped a SiON inorganic BARC layer in a standard P5000 Applied Materials PECVD reactor {1}. One of the major drawbacks with SiON is the interaction between nitride and DUV re sists : we observed footing with UV5 Shipley resist. A simple solution is t o have a surface treatment before lithography. Unfortunatly surface treatme nt can disturb optical properties of the material because ARC thickness and optical constants controls have to be very accurate. In this paper we desc ribe the surface treatment validation sequence : effect of the treatment on the resist footing influence of the surface treatment on resist swing curve efficiency of the treatment on the resist line's crossing topographic step technology time stability of the surface treatment influence of rework and stripping on the treatment. Finally we demonstrate the feasability of 0.25 mu m NVM lithography with in organic BARC.