Yoshihiko Sakane

The development of a high-performance perfluorinated polymer electret and its application to micro power generation

Recently, micro power generation using electrets has attracted much attention due to its large power output at a low frequency range. Since the theoretical power output is proportional to the square of the surface charge density of the electret, the development of a high-performance electret is required. In the present study, it is shown that the surface charge density of a CYTOP electret is significantly improved by the addition of terminal groups. Based on this fact, a novel high-performance polymer electret has been developed by doping a silane-coupling reagent into the polymer. A series of measurements of surface potential and TSD (thermally stimulated discharge) spectra was made for various CYTOP films prepared with different silane-coupling reagent concentrations. It is found that the surface charge density, charge stability and thermal resistibility of electric charges are markedly improved by the doping. A surface charge density of 1.5 mC cm−2, which is three times larger than that of Teflon AF, has been obtained on a 15 µm thick film. In addition, the thermal stability of the CYTOP electret is superior to that of Teflon AF. Power generation experiment is also performed using the patterned CYTOP electret of 20 × 20 mm2. At a low seismic frequency of 20 Hz, 0.7 mW power generation has been accomplished, which is about 2.5 times higher than our previous result.

Seismic Power Generator Using High-Performance Polymer Electret

Development of a micro electret generator prototype for energy harvesting applications is presented. MEMS-friendly perfluoropolymer, CYTOP is adopted as high-performance electret material. When corona charging is employed, charge density as large as 1.37 mC/m2is obtained for a 15 mm-thick CYTOP film, which is much larger than that of Teflon AF. In power generation experiments using a prototype seismic generator, maximum output power of 38 mW is obtained with 2 mmp-poscillation at 20 Hz.

Low-loss single-mode terahertz waveguiding using Cytop

A polymer-based, Cytop planar photonic crystal waveguide (PPCW) was designed for guiding terahertz radiation. Results indicate that the propagation and coupling losses in the 0.2–1.1THz range are relatively small for a sheetlike thickness design. Spectral analysis of the transmission data reveals frequency selectivity of the PPCW. Calculations of the spatial distribution of the terahertz electric field through the waveguide show evidence of single-mode propagation at a 0.45THz central frequency. The highly transparent nature of Cytop from deep ultraviolet to the far infrared region indicates its potential use as an integral component in hybrid optics.

All-polymer 8×8 AWG Wavelength Router using Ultra Low Loss Polymer Optical Waveguide Material (CYTOP TM )

All-polymer 8×8 AWG wavelength router with 200 GHz channel spacing around 1550 nm was fabricated using Asahis ultra low loss polymer waveguide material PBVE (CYTOP™) exhibiting low insertion loss as well as low temperature dependence.

Waveguide of amorphous perfluoropolymer for visible light

We developed an amorphous polymer of cyclized perfluoropolymer, which is highly transparent throughout the visible range, and fabricated waveguides of the polymer for visible light. At a wavelength of 405nm, approximately 60% of lightwaves are propagated through the straight waveguide and over 50% of the lightwaves are propagated through the buried waveguides with a radius of more than 30mm, demonstrating the feasibility of the waveguides as light sources with a small angle of a beam divergence in a single mode. The waveguides are prospective candidates for multiple beams in line for parallel information processing, such as optical recording systems.

Transmission characteristics of lens-duct and photonic crystal waveguides in the terahertz region

Transmission characteristics of lens-duct, Cytop planar photonic crystal waveguide (PPCW) and hollow-core microstructured optical fiber were analyzed in the terahertz (THz) region. The lens duct was able to channel and couple the THz radiation into a Teflon waveguide with a loss of about 0.7 dB. Single-mode propagation and frequency-selective properties were achieved using PPCW whose central frequency is at 0.45 THz. Results of time-domain spectra of the hollow-core microstructured polymer optical fiber showed a difference of about 20 ps between the THz waves that propagated in the core and cladding. Frequency shift of the transmission bands between waveguides of different size suggested photonic bandgap guidance. Finite-difference time domain calculations agreed relatively well to the experimental results of PPCW and hollow-core fibers.

Development of high-performance purfluorinated polymer electret

Recently, micro power generation using electret-based electrostatic induction attracts much attention due to its large power output at low frequency range. Since theoretical power output is proportional to the square of the surface charge density of electret, development of high-performance electret is required. Boland et al. employed Teflon reg AF (Du Pont) as their electret film. We previously found that perfluorinated polymer CYTOPTM CTL-M (Asahi Glass Co., Ltd.) shows high surface charge density of 1.3 mC/m2 (at the thickness of 16 mum), which is 3 times larger than that of Teflon AF. This paper presents a new high-performance polymer electret with higher surface charge density, stability, and high thermal resistibility of electric charges.

Nano-metal-ink-based electrode embedded in parylene HARS with the aid of the capillary effect

Microfabrication technology for free-standing parylene high-aspect-ratio structures (HARS) with embedded electrodes has been developed. Nano- metal ink is infused into capillaries in parylene HARS using the surface tension force. Micro electrodes in complex parylene springs have been successfully developed, and their robustness is demonstrated under large-amplitude in-plane vibration of the springs.

D212 Development of high-performance perfluorinated polymer electret for micro seismic power generation

This paper describes a new high-performance polymer electret with high surface charge density, stability, and high thermal resistibility of electric charge. We found that MEMS-friendly perfluorinated polymer CYTOP shows excellent electret properties and the thermal stability by doping silane coupling reagent into the polymer. The charge density of 1.5 mC/cm, which is 1.6 times larger than that of the undoped CYTOP, has been obtained on 16 μm-thick film. The power generation of 0.7 mW at a low seismic frequency of 20Hz was also accomplished, which is about two and a half times higher than the reported data.

Planar terahertz waveguide using CYTOP; a highly transparent plastic feasible for hybrid optics applications

A low-loss CYTOP planar photonic crystal THz waveguide with single-mode propagation is realized. The highly transparent nature of CYTOP from deep ultraviolet to the THz region indicates its potential usage as component of hybrid optics.