The sintered CdS/CdTe thin-film photovoltaic cells have been prepared on borosilicate glass substrates by successively repeating screen printing and sintering. The preparation conditions of the sintered CdS/CdTe cell for a visible-light-radiation sensor were investigated. The sintering condition of CdTe film has a strong influence on the electrical and the optical properties of the CdS/CdTe junction. The optimum sintering condition of CdTe on the as-sintered US film with less 0.1wt% of CdCl₂ was 600-620°C for 60 minutes.
The sintered CdS/CdTe photovoltaic cells show a spectral response of the quantum efficiency nearly constant in the range of 530 to 850nm. The temperature coefficient of short-circuit current density is almost constant in the range of -50 to 70°C. The temperature coefficient of open-circuit voltage is about -1.85mV/°C. The cell shows a linear dependence of short-circuit current density on light intensity over the whole measurement range. A photosensitivity under a white fluorescent lamp and a response time of the cell are about 0.7nA/mm²⋅lx and about 3μs respectively. These values of the CdS/CdTe cells are comparable to those of a typical single crystal silicon p-n photodiode. The sintered CdS/CdTe photovoltaic cell can be used as a visible-light-radiation sensor.

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Pb (Zr, Ti) O3 piezoelecteric thick films have been prepared on Pt/Cr/SiO2/Si by means of an improved jet printing system (JPS). X-ray diffraction (XRD) and scanning electron microprobe (SEM) analysis and measurements of electrical properties including dielectricity, ferroelectricity and piezoelectricity have been carried out on films. A very high depossition rate of 3μm/min and films with thickness above 100μm have been obtained without peeling. However, the films prepared in this fasion demonstrate lower piezoelectric behavior than bulk PZT ceramics. The reason for this has been explored by using element analysis.

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A sensing head for a high frequency ultrasonic transducer was created by direct bonding between Al and Pb(Zr, Ti) O₃ (PZT). The forming of hydrogen bridges at the interface was used as the bonding method in this study. After the surface was treated hydrophilically by bombardment of positive ions formed by introducing water into an ion source, the hydrophilictreated surfaces were placed in contact with each other and heated at above 250°C in the air. It was determined that the bonded device had sufficient bonding strength. In respect to characteristics of acoustic wave propagation, the signal is not distorted by the multiple reflections in the direct bonding interface. The frequency of the ultrasonic transducer was 17MHz. Thus, the high frequency sonar has ahigh resolution. The present bonding method may be successful for assembling the ultrasonic transducer of a micromachine.

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Al and PZT{Pb(Zr, Ti)O₃} were directly bondable by forming hydrogen bonds at the interface. The strength of the bond and the structure of the interface were investigated. This technique was applied to the direct bonding between a PZT stacked actuator and an Al radiator plate on an in-pipe micro inspection machine, and the heat transmission effects of direct bonding on the micro inspection machine have been compared with the adhesive bonding.
First, the Al and the PZT were treated so that their surfaces were hydrophilic, then OH groups were adsorbed by a physical reaction in which the surfaces are bombarded with ions produced by passing the steam through anion source. The surfaces were then placed in contact with each other in the air, then heated above 250°C in a vacuum to remove the residual water molecules from the bonding interface.
The observation with a thermo-viewer shows that the saturated temperature of the PZT stacked actuator at the driving frequency of 1kHz is suppressed below 93°C by the direct bonding of the Al radiator plate as compared with 110°C of adhesive bonding. Walking speed of the in-pipe micro inspection machine which utilizes the direct bonding was successfully stabilized compared with the adhesive bonding.

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Gas sensors for detecting SF₆ decomposition products are being actively pursued as low cost instrumentation for detecting and locating faults in GIS. We developed an amperometric solid state ionic sensor using high ionic conductive solid. The sensor responded to the changes in HF concentration ranging from 1 to 10wt.ppm in SF₆ gas at 1 atm. The rapid rising current based on the electrode reaction was detected in a few minute and gradually increased toward a stationary state. After purging the sample gas, the output current reduced and returned to the base line.
We have revealed that amperometric solid state ionic sensor has strong possibility for detecting SF₆ decomposition products and locating faults in GIS.

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