The electrical and optical characteristics of indium-doped Se 2 Sb 2 Te 6 phase-change alloy are studied in this paper. It is found that adding indium to Se 2 Sb 2 Te 6 alloy increases its amorphous-crystalline transition temperature, T C , and reduces the electrical conduction activation energy. The capacitance-temperature measurements showed a drastic change in the capacitance of the modified film as the temperature approaches T C and eventually the capacitance becomes negative and nonlinear. The negativity and nonlinearity in the capacitance-voltage dependence can be attributed to the growth of conductive crystalline islands with increasing temperature.

Field emission characteristics of a cathode consisting of SiC micropowders with sharp edges were examined. Emission current from the cathode followed the Fowler–Nordheim relationship; therefore, it was confirmed that the SiC micropowders acted as the field electron source. A field enhancement factor of ∼1000 was obtained. This value was comparable to that of conventional emitters. A good short-term stability of the fluctuation in the emission current from the cathode, which was less than 7% of the total emission current, was determined.

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Seedless crystallization of Ge and GaSb melts was achieved under microgravity occurring in a drop-shaft capsule. It was observed that melts levitated in Ar atmosphere, formed into a spherical shape and were solidified instantaneously when they collided with the container quartz wall. X-ray diffraction pattern of these samples showed clear Laue spots signifying a single-crystal structure, while Ge or GaSb solidified in crucibles under normal gravity did not show Laue spots. These results indicate that single crystal growth rapidly occurs without seed crystals from the spherical melt under microgravity. This can be understood by assuming that an ordered structure like a single crystal is already formed in a levitated melt, and assists rapid crystallization when the melt touches the crucible wall and latent heat is deprived.

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