Recently, the requests for actuator are small size, high output power and lower electrical power, and so on. We are
focusing on an electromagnetic type actuator. Nonetheless, this type actuator is known to be unsuitable for
miniaturization because an allowable current carrying capacity is small. Therefore, we fabricated microcoil with narrow
pitch and high aspect ratio using deep X-ray lithography and metallization techniques. If the aspect ratio is increased,
cross section area of coil lines is also increased allowing a greater current path. We have fabricated coil lines with the
width of 10 μm and the aspect ratio of over 5 on acrylic pipe surface. For current paths, copper layer was formed
between narrow pitch thread structures on pipe by electroforming. Finally, isotropic copper etching was performed until
the insulated portions of the wiring were exposed. We have estimated a suction force of electromagnetic actuator using
this microcoil. The theoretical values by simulation and actual measurements of suction force were compared. These
results are relatively in good agreement with theoretical values. Thus, it is very expected that microcoils with high
aspect ratio and microactuators with high output force could be manufactured in spite of the miniature size.
Actuators are finding increasing use in the various fields. And, it is one of the most important parts of machine in
motion because of determine its performance. Recently, the demands for various actuators are smaller size, higher
output power, lower input electrical power, and so on. To realize these demands, the key technology is processing of
microfabrication. We achieved development of the three-dimensional deep X-ray lithography technique for the spiral
micro coil with a high inductance. Therefore, we have fabricated and estimated the solenoidal electromagnetic type
microactuator of a low driving power by using this technique. This actuator having the high aspect ratio of coil line is
also expected a great force in spite of miniature size. Now, we have obtained the coil line with the width of 10 μm and
the aspect ratio of 5. We have also fabricated the measurement system for suction force of electromagnetic actuator. The
coil model was measured by this system, and results were relatively in good agreement with simulation results. Using
this high aspect coil made by X-ray lithography technique, the electromagnetic actuators have been expected to
manufacture with high output force in smaller size.
Strict control of the amount of water in soils is one of the most important environment factors for crop growth, so it would be useful to be able to determine the amount of water distributed through the soil at all times. We have therefore proposed a new system for measuring the amount of water in the soils. It achieves this by measuring transitions in the temperature distribution in the soil using infrared ray sensors. The ground surface temperature obtained from infrared ray sensors is different with and without the presence of water. Therefore, we can determine the amount of water that is present from transitions in the temperature distribution when using in this system. Because it uses infrared ray sensors, this system has the great advantage that is enables non-contact, real time measurements of the distribution of water in the ground. If this system were to be developed further, increased efficiency might be expected in some areas of agricultural fields.
The fabrication methods and performances of CdTe radiation detectors in a p-i-n structure which helps to reduce the leakage current are reported. Two different types of doping methods were studied in order to attain heavily doped CdTe layers. One is the hydrogen plasma- radical-assisted metalorganic chemical vapor deposition (HPRA-MOCVD) and the other is the excimer laser processing, both of which are carried out at a low temperature. Using the HPRA-MOCVD, iodine doped n-type CdTe layers with carrier concentration around 1018 cm-3 and electron mobility of 100 cm2/V-s were grown epitaxially on the GaAs substrates at a low temperature of 150 degrees Celsius. As the other method, excimer laser was irradiated on the high resistivity CdTe crystals (resistivity: 109 (Omega) cm) by depositing a thin layer of dopant materials like Sb, Na2Te, or In on the crystals surfaces. For the Sb and Na2Te dopant, heavily doped p+-type thin layer was formed on the CdTe crystal, whereas In dopant exhibited n+-type layer. Carrier concentrations in those laser doped layers were in the order of 1019 cm-3. These low temperature processes can be adapted for the fabrication of CdTe and CdZnTe detectors.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.