We developed step edge decoration method for the fabrication of semiconductor ZnO nanodots and nanowires using pulsed laser deposition. We synthesized high quality ZnO nanowires with the small diameter of about 20nm and the uniform interval of about 80nm between each nanowire, which has a simple structure for the formation of contact electrodes. The ZnO nanowire-based sensor was prepared only with the simple process of a gold electrode formation. The ZnO nanowire-based sensor exhibited the high surface-to-volume ratio of 58.6μm−1 and the significantly high sensitivity of about 10 even for the low ethanol concentration of 0.2ppm.

A high-temperature MEMS heater using suspended serpentine silicon beams as a filament is proposed for an infrared light source. The MEMS heater utilizes suspended silicon beams for thermal isolation and the mechanical support of heat resistors, and Pt/Ti layers for a Joule heating resistor deposited onto suspended silicon beams. An SiO 2 insulator layer was deposited to provide electrical isolation between the thermal resistor and the silicon substrate. The proposed MEMS heater did not require a closed membrane-based back-cavity structure for thermal isolation. The heater is capable of being simply fabricated by a single photolithography process and subsequent silicon anisotropic etching and metal deposition processes. The fabrication process and driving characteristics of the MEMS heater are described. High temperature achieved by the heater was measured by IR camera image processing.

A method to fabricate suspended silicon nanowires that are applicable to electronic and electromechanical nanowire devices is reported. The method allows for the wafer-level production of suspended silicon nanowires using anisotropic etching and thermal oxidation of single-crystal silicon. The deviation in width of the silicon nanowire bridges produced using the proposed method is evaluated. The NW field-effect transistor (FET) properties of the device obtained by transferring suspended nanowires are shown to be practical for useful functions.

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Efforts to date in silicon nanowire research have primarily focused on the nanowire synthesis and the demonstration of individual nanowire-based devices exhibiting interdisciplinary potential spanned from electrical (Duan et al 2003 Nature 425 274–8; Cui and Lieber 2001 Science 291 851–3; Morales and Lieber 1998 Science 279 208–11) through biomedical applications (Cui et al 2003 Science 293 1289–92; Zheng et al 2005 Nature Biotechnol. 23 1294–301). However, the realization of integrated nanowire devices requires well ordered assembly of a silicon nanowire (Huang et al 2001 Science 291 630–3; Whang et al 2003 Nano Lett. 3 1255–9) as well as simple and cost effective fabrication. Here we describe a simple fabrication scheme and a large-scale assembly of silicon nanowires by combining top-down fabrication with nanowire transfer onto another insulator substrate for device manufacture. Our innovative fabrication method enables us to obtain well defined silicon nanowires as a freestanding bridge structure with a diameter of 20–200 nm and a length varying from 5 to 100 µm using micro-machining processes. Direct transfer of the freestanding nanowires simply provides large-scale assembly of silicon nanowire on various substrates for highly integrated devices such as high-performance thin-film transistors (TFTs) (Duan et al 2003 Nature 425 274–8; Ishihara et al 2003 Thin Solid Films 427 77–85) and nanowire-based electronics (Cui and Lieber 2001 Science 291 851–3). Electrical transport properties of the transferred silicon nanowire were also investigated.