The preparation of two inch double-sided YBCO thin films by simultaneous sputtering from a single target is reported. The lateral homogeneity of microwave surface resistance of the YBCO thin films, on both sides of the two inch wafer, is characterized by using a Fabry–Perot resonator at 145 GHz and 75 K. Values of microwave surface resistance Rs (75 K, 145 GHz, 0 T) below 55 mΩ were reached over the whole area of YBCO thin films on two inch LaAlO3 wafers. The majority of the wafer area has Rs (75 K, 145 GHz, 0 T) values in the range of 15 mΩ to 40 mΩ. The uniformity of Rs values in the whole two inch wafer is excellent and the properties of YBCO thin films were found to be very similar on both sides of the wafer.

A planar waveguide is fabricated by 3 MeV O2+ ion-implanted in MgO-doped lithium niobate, and the refractive index profiles of waveguides are reconstructed based on etching and ellipsometry techniques. The SRIM2003 code is used to simulate the damage distribution induced by implantation. The etching rate versus the etching depth is extracted and the relation between the etching rate and the damage profile is discussed. The index profile of this kind of waveguide is determined by etching in combination with the following ellipsometric measurements. Both ordinary and extraordinary index profiles in waveguide are obtained. The influence of damage profile on index profiles in waveguide, as well as that on waveguide properties is analysed.