The surface resistance of Ag, Au and A1 thin conducting films deposited on low loss dielectric substrates at microwave frequencies using TE011 mode single post-dielectric resonator (10-13.22 GHz) was measured to calculate their conductivity in relation to layers thickness. This method enabling measurements near metal-insulator percolation transition was also applied for epitaxial graphene deposited on semi-insulating SiC. Moreover, effective microwave conductivity has been determined for intentionally made aluminum island structure where the DC conductivity is equal to zero. Special attention was paid to films thickness measurements which is critical for accuracy of sheet resistance calculation. Conductivity of thin metal layers and very thin graphene was compared.

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BaTiO 3 (BT) nanocrystalline thin films were plasma etched in the course of several experiments which varied in RF power as well as CF 4 /(CF 4 + Ar) gas-mixing ratio. The maximum etch rate of approximately 30 nm/min was observed for the maximum power (300 W) and pure Ar plasma atmosphere, which indicates that the process is controlled by the physical mechanism of Ar ion bombardment, while the increasing content of chemically active plasma component (CF 4 ) in the gas mixture slows down barium titanate etch rate.

Electrical properties of isotype n-ZnO/n-4H-SiC and anisotype n-ZnO/p-4H-SiC heterojunction diodes have been investigated and compared. The influence of the electron concentration in ZnO on diode parameters has been also examined. ZnO/4H-SiC heterojunctions fabricated by atomic layer deposition of ZnO on bulk 4H-SiC substrates show highly rectifying behaviour with leakage current values lower than 10−11A. The isotype heterojunction diodes demonstrate better electrical properties than anisotype heterojunction diodes, in particular lower values of ideality factors (1.13–1.2 as compared to 1.36–1.52), series resistance (5–7 Ω as compared to 66–80 Ω), capacitance (2 times lower, at 0 V), and built-in voltage (1.13–1.42 V as compared to 1.78–1.87 V). Diodes with higher doped ZnO layers show lower series resistance and built-in voltage as compared to diodes with lower doped ZnO layers. Isotype as well as anisotype heterojunction diodes demonstrate a strong influence of UV-light illumination on reverse current-voltage characteristics; however, isotype structures with n-4H-SiC show lower reverse current under cyan (λ = 488 nm) light illumination as to anisotype structures with p-type 4H-SiC, due to the lack of donor-acceptor pair absorption. This makes ZnO/4H-SiC isotype heterojunction diodes more suitable for visible-blind UV photodetectors than the anisotype ones.