Ikunori Kobayashi

Plasma-Enhanced Chemical Vapor Deposition of Silicon Nitride

The optimum condition of plasma-enhanced chemical vapor deposition to deposite silicon nitride (SiNx) film and its application as a gate insulator of a-Si thin-film transistor (TFT) have been investigated. The internal stress of SiNx in the range of 4.3×109 dyn/cm2 tensile to 8.0×109 dyn/cm2 compressive is found to be controllable by changing the ratio of H2 and N2 in the source gases without affecting the optical band gap. Satisfactory TFT characteristics and high reliability are realized by using a gate insulator of SiNx having either stoichiometric or N-rich composition which shows the large optical band gap.

Development of automatic hologram synthesizer for medical use IV: liquid-crystal spatial light modulator

A liquid-crystal (LC) spatial light modulator for hologram synthesis consisting of a high resolution twisted nematic LC-panel of active matrix type has been developed. Output images with signal-to-noise ratio of 30 dB and maximum contrast ratio over 600 were obtained. The stability of the displayed image was analyzed on the basis of two beam interferometry. Confirmation of no appreciable degradation in diffraction efficiency was obtained.