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Screen printing has various industrial applications owing to its simple process and low production cost. With advancement in electronic devices, the demand for fine electrode patterns is gradually increasing. In this study, a novel method for fabricating a hybrid fine metal mask (HFMM) was developed to enable the screen printing of fine electrode patterns. The HFMM was designed to combine the advantages of the conventional screen mask and metal stencils; it was fabricated through photolithography and the electroforming process. The HFMM comprised three parts: a stencil, a bridge, and an anti-sticking feature. A conductive ink, which was passed through the stencil feature, was deposited on the substrate and the bridge feature helped increase the mechanical rigidity of the HFMM. The anti-sticking feature was fabricated for the easy separation of the HFMM from the substrate during the printing process. In this study, the printing feasibility of HFMM to the screen printing process was tested to fabricate fine electrodes with a line width of approximately 10 μm, and the printing and electrical properties of the electrodes were evaluated. The screen printing process with HFMM could be applied to fabricate various functional electrodes, such as stretchable and transparent electrodes.

This study reports on the fabrication process of a nanomesh-shaped nickel mold by using phase shift lithography. We also present its application to a transparent electrode film for a touch screen panel. A suitable gap between the checkerboard- shaped patterns on a photomask was chosen to obtain the nickel mold with a mesh-shaped pattern connected to each other. A nanomesh-type trench pattern was transferred from the nickel mold onto a polyethylene terephthalate film through the imprinting lithography process with ultraviolet light. The nanomesh- embedded electrode pattern was fabricated by filling the nanotrench with Ag paste. The light transmittance and sheet and line resistance of the nanomesh-type transparent conducting electrode film were evaluated. The TCE film was then applied to a 7 in. touch sensor module.

A cost-effective process for producing high-performance Ag-paste-based flexible transparent nanomesh electrodes (FTNEs) was developed by optimizing their linewidth, pitch, and height. These nanomesh electrodes, with a linewidth of several hundred nanometers and a pitch of 10-200 μm on a PET substrate, achieved wide ranges of transmittance (83.1%-98.8%) and sheet resistance (1.2-30.9 Ω/sq) and a figure of merit (992-1619) superior to those of indium tin oxide and silver nanowire (AgNW) electrodes. Our evaluation of their flexibility (testing up to 50 000 cycles) and their electromagnetic interference shielding effectiveness verifies the applicability of these FTNEs to various flexible optoelectronic devices.

Because of the intriguing electrical and mechanical properties of carbon nanowires, many researchers exploit them by incorporating them in many applications such as field emitter and sensors. Despites the many advantages of carbon nanowires, they are not widely used in real applications because of the difficulty in positioning them at the desired location, even though many methods have been attempted to achieve this goal. Here we show that we can grow carbon nanowires by corona-discharge-assisted thermal chemical vapor deposition (CVD). A chrome/nickel bilayer was used as the electrode to generate the corona discharge. Additionally, nickel acted as the catalyst to initiate carbon growth and chrome acted as the structural support. C2H4 gas flow was introduced into the growth tube as the carbon source at a certain growth temperature. Experiments were conducted to grow the carbon nanowires horizontally and vertically.

We anticipate the development of new real time biological active point (BAP) systems based on skin impedance, since this measurement method has the superior characteristics of noninvasiveness and easy operation. In this paper, we report on the three electrode measure method that has the advantage of measuring the impedance of the BAPs under the skin. This system easily measured the potential difference between the measurement electrodes and reference electrodes. The BAPs have lower impedance at all frequencies and their reactance is much smaller than that of the surrounding skin. The characteristic frequencies of BAPs are about 20-30HZ higher than that of the surrounding skin. This technology analyzed accurately and objectively the reactance and characteristic frequency of BAPs.

In this paper, the carbon nanowires grown between the microgap by corona discharge assisted thermal CVD is discussed. The experiments have been done in three different temperatures, 500, 600 and 700degC. At 700degC, because of too high local temperature, the electrodes are damaged and the carbon nanowires grow very densely and extend over the gap between the electrodes. By using this method, it is able to lower the growth temperature which enables to widen the materials used as the electrodes and the applications. This method can be used to fabrication the nanowire sensor.

Since their discovery in 1991, Carbon nanotubes (CNTs) are known to have unique electrical, mechanical and thermal properties and have been used at many applications. For using at applications, the manipulation of the CNTs is very important. Recently, Dielectrophoresis has attracted much interest for CNTs alignment and deposition on a desirable location, but all the work have been done on plane electrodes. In this work, We propose a novel fabrication method of carbon nanotube bridge in V-groove channel using dielectrophoresis. Compared to the case using plane electrode, this method has several advantages. The electrodes in V-groove channel provide high and parallel electric field and eliminate nonspecific CNTs deposition so that efficiency of CNTs alignment increases. V-groove channel was fabricated on silicon wafer by TMAH bulk etching. The gold electrodes were deposited in V-groove channel. To prepare the SWNTs suspension, SWNTs were dispersed in DI water with 0.1 wt% sodium dodecyl sulfate by sonication. A drop of suspension was introduced onto the electrodes and ac voltage was applied. When SWNTs alignment on a electrodes in V-groove is compared with that on a plane electrodes, SWNTs were aligned to electric field direction and formed SWNTs bundle bridges cross V-groove channel. These carbon nanotube bridges have diameter of 0.5-2 mum and length of 5~20 mum. We think that this phenomenon was happened by 3D electric field in V-groove channel. Because these bridges had regular shape and wide contact areas, these bridges can have uniform electric properties and lower contact resistance, but the phenomenon need a further theoretically studies. SWNTs bridges can be used in various sensors. Because sensor bridges were away from surface, effects of surface reduced and signal to noise ratio increased. High surface areas of SWNTs bridges can improve sensitivity of sensors, and embedded SWNTs bridges in microchannel can be easily used at various microfluidic applications without additional work.