The electrochemical capacitance-voltage (ECV) technique can practically profile carrier concentrations on textured surfaces, but reliable calibration of the surface area is strongly demanded since it plays a decisive role in calculating both the carrier concentration and the profiling depth. In this work, we calibrate the area factor of pyramidally textured surfaces by comparing ECV profiles with cross-sectional scanning electron microscopy image, and found out it is 1.66, and not 1.73 which was formerly assumed. Furthermore, the calibrated area factor was applied to POCl 3 and BBr 3 diffusions which resulted in comparable diffusion profiles for both textured and polished surfaces.

We developed a frequency-modulation atomic force microscopy (FM-AFM) system combined with Kelvin probe force microscopy (KFM) and scanning capacitance force microscopy (SCFM). Using the developed system, we investigated the surface structure and electrical characteristics of a bulk heterojunction (BHJ) sample consisting of a mixture of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and poly(3-hexylthiophene) (P3HT). The BHJ structure consisted of PCBM and P3HT molecules. These materials are often used as the active and charge transport layers in an organic solar cell, respectively. The results suggest that we succeeded in visualizing the phase separation in the BHJ sample using SCFM measurements. We illustrated the energy band diagrams from the KFM results and showed that band bending occurs from the organic material side at the interface with the indium–tin oxide substrate. Furthermore, the KFM and SCFM results suggested that charge separation occurs in the BHJ structure.

Silicon oxide thin films were grown from the liquid source, polysilazane, by using mist chemical vapor deposition (CVD) at temperatures of 200–350 °C. The films were grown with a reasonable growth rate of 12 nm/min at the temperature of 200 °C, and they showed resistivity of the order of 1013 Ω·cm, although the incorporation of carbon and oxygen remains as a problem to be discussed and solved in the future. The results are encouraging for the future application of mist CVD for the growth of silicon oxide films on plastic substrates.

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Small molecular material, aluminum tris (8‐hydroxyquinoline) (AlQ3), was found to be soluble in methanol under application of high ultrasonic power, and this has opened safe and environmental‐friendly solution‐based deposition of thin films. The chemical state of AlQ3 was analyzed by nuclear magnetic resonance study and the results showed there was no severe damage on AlQ3 atoms applied by high ultrasonic power. The AlQ3 films were fabricated by ultrasonic‐assisted mist deposition method on indium‐tin‐oxide. The low leakage current suggested well‐defined AlQ3 thin films without significant electrical defects such as pinholes.