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Optically high quality coatings of fluoride materials are required in deep ultraviolet (DUV) lithography. We have applied ion-beam sputtering (IBS) to obtain fluoride films with smooth surfaces. The extinction coefficients were of the order of 10(-4) at the wavelength of 193 nm due to the reduction of their absorption loss. The transmittance of the MgF2/GdF3 antireflection coating was as high as 99.7% at the wavelength of 193 nm. The surfaces of the IBS deposited films were so smooth that the surface roughness of the A1F3/GdF3 film was comparable with that of the CaF2 substrate. The MgF2/GdF3 coating fulfilled the temperature and humidity requirements of military specification. Thus, the IBS deposited fluoride films are promising candidate for use in the DUV lithography optics.

We have investigated the dielectric properties up to microwave frequencies of ceramics represented as (Pb1-x Ca x )-(Me m Nb1-m )O3 where Me is selected from Li, Na, Mg, Zn, Ni, Co, Fe, Y, Yb, Al and Cr. High Q values and small temperature coefficients of resonant frequency were obtained in (PbCa)(Mg1/3Nb2/3)O3, (PbCa)(Ni1/3Nb2/3)O3 and (PbCa)-(Fe1/2Nb1/2)O3 with perovskite structure. These dielectric constants and the Q values for a near-zero temperature coefficient are εr=73 with Q=1330, εr=59 with Q=1700 and εr=91 with Q=1650, respectively. The other ceramics with smaller amounts of perovskite phase had degraded characteristics, i.e., low Q values or large temperature coefficients. In lead- and calcium-based perovskite, it seems that the high dielectric constant occurs due to Pb content in A-sites and smaller average ion radius in B-sites.

Dielectric properties of alkaline-earth-substituted PbZrO3 ceramics up to microwave frequencies were investigated. Although there were no preferable characteristics in the Ba- or Sr-substituted system, the ceramics in a (PbCa)ZrO3 system showed not only high dielectric constants in the range of 100 to 118, but also high Q values of 1000 to 1150 and small temperature coefficients of resonant frequency of 0 to 30 ppm/ °C. The crystal structure of the Ca-substituted ceramics was also investigated by X-ray powder diffraction. The structure changed from PbZrO3-type orthorhombic to CaZrO3-type orthorhombic through cubic and rhombohedral with increasing Ca substitution. Coaxial dielectric resonators made of the selected above material had Q values in the range of 430 to 450 at the 900 MHz band.

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