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We present the effects of ion bombardment on ZnO nanowires caused by their exposure to an Ar inductively coupled plasma. The conductivity of the individual ZnO nanowire was increased in up to 3 orders of magnitude due to increase in both carrier concentration and mobility, with a substantial negative shift in the threshold gate voltage also being observed. The drastic changes in the electrical properties were attributed to the decrease in species adsorbed on the surface, as well as to the increase in oxygen vacancies near the surface caused by ion bombardment.

A new type of inductively coupled plasma (ICP) utilizing an array of auxiliary discharges enhanced with ferromagnetic cores and placed at the chamber side is developed and characterized over a wide range of discharge conditions. The ICP electrical and plasma characteristics are measured over a wide range of discharge powers and argon gas pressures. It is shown that at 400 kHz driving frequency the antenna power factor of this ICP is close to 1, so the antenna voltage and current are much lower than those in a conventional ICP at similar rf power. Due to low driving frequency and low antenna voltage, the capacitive coupling in the ICP mode is practically eliminated, while due to enhanced ferromagnetic core coupling, the power transfer efficiency is higher than 95% at an rf power larger than 0.5 kW. Langmuir probe measurements show that the radial plasma non-uniformity over 300 mm can be less than 3%. This plasma source is expected to be suitable for large-scale plasma processing.

Low-adhesive surfaces have been highlighted due to the potentials to mitigate fouling issues by preventing unwanted substances from adhering. Realizing superhydrophobicity with 3D surface structures/chemical modifiers or fabricating lubricantassisted slippery surfaces has been demonstrated to realize lowadhesive surfaces. However, they still need to overcome the transition to Wenzel from Cassie states of droplets on 3D surface structures or the lubricant depletion issues of slippery surfaces for sustainable operations. Herein, we report the fabrication of lowadhesive polymeric surfaces, neither assisted by 3D surface structures/chemical modifiers nor lubricants, which is realized by embedding the interconnected pore networks underneath the top smooth surface using a water steaming method. The fabricated silicone surfaces exhibit low-adhesive properties due to the stress concentration effects generated by the subsurface-structured pores, favorable for easy detachment of the adherent from the surface. Our platform can be exploited to lower adhesion of superhydrophilic surfaces or to achieve ultralow-adhesive properties upon combination with superhydrophobicity. Finally, scale precipitation tests reveal 4.2 times lower scale accumulation of our lowadhesive polymeric surfaces than that in control samples.

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