Sergey V. Safonov

Laser-induced deposition of nanostructured copper microwires on surfaces of composite materials

Microelectronics industry is growing fast and the rate of new devices’ development increases every year. Therefore, methods for simple and high-precision metal coating on dielectrics are needed. Existing methods do not allow performing the high-precision metal deposition without using photomasks, while making photomask for each prototype is long and expensive process. One of the methods of maskless metal deposition is laser-induced chemical liquid-phase deposition (LCLD). In this work we show the effect of substrate surface type on a result of LCLD. Deposited copper structures were characterized by SEM, EDX and impedance spectroscopy. The results show that laser-induced copper deposition is highly affected by the surface being homogeneous or composite material. It was found that the deposits with low resistivity and high quality metal localization mostly appear on the two-phase surfaces. In contrast, deposits on one-phase surfaces exhibited poor topology of copper material.

Influence of surfactants on laser-induced copper deposition from solution

The influence of surfactants on the result of laser induced copper deposition from solution on the dielectric surface was studied. The dependences of the topology of the copper structures on the hydrophilic—lipophilic balance of non-ionogenic surfactants was found. The surface tension at the gas phase—solution interface was measured. The best results of laser deposition are obtained by the use of non-ionogenic surfactants with low values of hydrophilic—lipophilic balance.

Catalytic activity of copper nanostructures produced by laser-induced deposition technique

The method of laser-induced metal deposition from solution was applied in the continuous in situ laser generation of metal copper catalysts for model organic synthesis reactions. The gas phase products producing during laser-induced copper deposition were analyzed by mass spectrometry whereas solutions used for the copper deposition were investigated before and after laser irradiation using chromato-mass spectrometry and NMR spectroscopy. It was found out that the catalysis of the studied organic reactions by metal catalysts generated during laser deposition process occurs only upon laser irradiation of the reaction mixture.

Non-enzymatic glucose and hydrogen peroxide sensors based on metal structures produced by laser-induced deposition from solution

The method of laser-induced metal deposition was applied to synthesize nano- and microstructured metal electrodes for non-enzymatic glucose and hydrogen peroxide sensing. These electrodes were characterized by SEM, EDX, SIMS, XRD and EIS. Copper electrodes have a linear dependence of the current-concentration in the range of 10-100 μmol/L for hydrogen peroxide and 0.6-3.0 mmol/L for D-glucose.

Laser-induced copper deposition with weak reducing agents

The study showed that organic alcohols with 1,2,3,5,6 hydroxyl groups can be used as reducing agents for laser-induced copper deposition from solutions (LCLD).Multiatomic alcohols, sorbitol, xylitol, and glycerol, are shown to be effective reducing agents for performing LCLD at glass-ceramic surfaces. High-conductivity copper tracks with good topology were synthesized.