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High‐kperovskite oxide of barium strontium titanate (BST) represents a very attractive multi‐functional transducer material for the development of (bio‐)chemical sensors. In this work, a Si‐based sensor chip containing Pt interdigitated electrodes covered with a thin BST layer (485 nm) has been developed for multi‐parameter chemical sensing. The chip has been applied for the contactless measurement of the electrolyte conductivity, the detection of adsorbed charged macromolecules (positively charged polyelectrolytes of polyethylenimine) and the concentration of hydrogen peroxide (H2O2) vapor. The experimental results of functional testing of individual sensors are presented. The mechanism of the BST sensitivity to charged polyelectrolytes and H2O2vapor has been proposed and discussed.

Microwave impedance characteristics of the double velocity IMPATT diode structure made of Si/SiC heterostructures are examined.

Metal-semiconductor tunneling contact characteristics on the base of Silicon Carbide with trap levels in the semiconductor bandgap are theoretically examined. It is shown that the magnitude of avalanche voltage can be increased under the influence of trapping charge carriers tunneling from the metal to the semiconductor. It is shown that with the increased of temperature the breakdown avalanche voltage of the contacts is decreased.

Microwave impedance characteristics of the double velocity IMPATT diode structure made of Si/SiC heterostructures are examined.

Metal-semiconductor tunneling contact characteristics on the base of Silicon Carbide with trap levels in the semiconductor bandgap are theoretically examined. It is shown that the magnitude of avalanche voltage can be increased under the influence of trapping charge carriers tunneling from the metal to the semiconductor. It is shown that with the increased of temperature the breakdown avalanche voltage of the contacts is decreased.

pH‐sensitive properties of barium strontium titanate (BST) high‐k thin films as alternative gate material for field‐effect capacitive (bio‐)chemical sensors based on an electrolyte‐insulator‐semiconductor system have been investigated. The BST films of different compositions (Ba0.31Sr0.69TiO3, Ba0.25Sr0.75TiO3and Mg‐doped Ba0.8Sr0.2Mg0.1Ti0.9O3) were deposited by pulsed laser deposition technique from targets fabricated by self‐propagating high‐temperature synthesis. The realised sensors have been electrochemically characterised by means of impedance‐spectroscopy, capacitance–voltage and constant‐capacitance method. The sensors possess a Nernstian‐like pH sensitivity in the concentration range between pH 3 and 11 with a response time of 5–10 s. An equivalent circuit model for the BST‐based capacitive field‐effect sensor is discussed.

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Reaction of N-chloromethylpyrrolidone with the sodio-derivatives of malonic and substituted malonic esters in dry ether has given the diethyl esters of the corresponding 2-oxopyrrolidinomethylmalonic acids.