ArF lithography which is a leading technology for 100nm node device fabrication is approaching the stage of practical use, where resolution enhancement techniques (RET) represented by attenuated phase shift mask (att.PSM) are expected to be used from the beginning. ON the other hand, in order to obtain higher depth of focus and resolution, it is said that att.PSM with high transmittance (HT-PSM) will be adopted to KrF and ArF lithography. We have developed zirconium silicon oxide (ZrSiO) att.PSM and reported its utilities toward practical use of ArF lithography. In this paper, we present examination results of possibility of ZrSiON att.PSM to be applied to HT-PSM for KrF and ArF lithography. Consequently, we confirmed the possibility and effectiveness of ZrSiON for HT-PSM as follows; ZrSiON films are convenient to control optical properties required for HT-PSM because of its distribution of optical constants (n;refractive index, k;extinction coefficient) with deposition conditions. Bi- layer HT-PSM having transmittance of 15% for ArF of KrF lithography show such good spectral transmittance that they can be inspected with currently available inspection tool. ZrSiON blanks are also proved to have high durability against cleaning chemicals of not only acid but alkali. Moreover, ZrSiON shifter has good dry-etching durability against Cr dry-etching stacked on ZrSiON film, which makes it easy to control phase angle in fabricating tri-tone-type HT-PSM.