The deposition of device quality SiO2 thin films has been achieved in a large surface DECR deposition system. The values obtained for p (1-2 1016 Ωcm) and Ec (3-4 MV cm-1) are of the same order as the values previously reported showing that the extension of the DECR concept to up to 8" and more is possible. This method seems to be a promising one for the obtention of the gate oxide of polysilicon TFTs as it is simplier than the previously reported double step procedure and as it does not require substrate heating, which, in the case of glass substrates, would increase the processing time.