Thick-film hybrid microwave filters made in PolyTherm CVD diamond substrates

The realisation of microwave integrated circuits consisting of numerous elements and components, both passive and active, takes place in steps. Initially, experimental constituent elements are designed and constructed, and only after it is found that they satisfy the operating conditions, can they be integrated into a sub-system. As a result of this we obtain complicated Microwave Integrated Circuits (MICs). Initially however one has to construct basic MIC elements such as: resonators, filters, couplings, Y branch joints, circulators, etc. During research over several years carried out at the Private Institute of Electronic Engineering and Cracow University of Technology, Academy of Mining and Metallurgy and Technical School of Communication and devoted to the application of thick-film technology to MIC, the authors have devised and constructed several microwave elements using strip-lines and this paper reports of the results of their studies. The construction of the filters involved the use of a new type of dielectric material with high constructions were produced by the use of thick-film technology and gold pastes manufactured by Du Ponte. An interesting means of compiling the extreme resonators with the strip-line was employed. PolyTherm ET 100 CVD diamond substrates, were used. Examples of filter construction and their frequency characteristics are given.