The changes in the characteristics of microstrip rejection filter and simple microstriplines due to bulk and thin film dielectric overlay are reported in this paper. Al₂O₃ overlay both bulk and thin film increases theQ of the filter. All other overlays decrease theQ. TiO₂ thin film shows improvement inQ whereas with bulk TiO₂ the filtering property is not observed. The effect of overlays on simple lines is to reduce the transmission without much effect in the reflection.

Microstriplines were coated with Al₂O₃ by chemical vapour deposition to get homogeneous thin film overlay. The paper reports the decrease in the total power loss in such microstrips. The frequency response from 2–6 GHz is studied for the overlay effect.

Superconducting thin films of Y₁Ba₂Cu₃ O_{7 −x} have been deposited on (100) Y-ZrO₂ substrates by pulsed excimer laser ablation from anunreacted mixture of Y₂O₃, BaCO₃ and CuO. The films deposited at substrate temperature of 680°C and oxygen partial pressure of 200 mtorr were found to be superconducting with zero resistive transition temperature of 89 K and critical current density of over 3 × 10⁵ A/cm² at 77 K. These results are compared with those obtained by laser ablation from a sintered superconducting pellet.

A study was conducted to ascertain the effect of variation in spin speed and baking temperature on $\beta$-phase content in the spin-coated poly(vinylidene fluoride) (PVDF) thick films ($\sim$4−25 $\mu$m). Development of $\beta$-phase is dependent on film stretching and crystallization temperature. Therefore, to study the development of $\beta$-phase in films, stretching is achieved by spinning and crystallization temperature is adjusted by means of baking. PVDF films are characterized using Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and scanning electronmicroscopy. It is observed that crystallization temperature lower than 60$^{\circ}$C and increase in spin speed increases the $\beta$-phasecontent in PVDF films. Crystallization temperature above 60$^{\circ}$C reduces $\beta$-phase content and increases α-phase content. It was also observed that viscosity of the PVDF solution affects the β-phase development in films at a particular spin speed.