Very highly sensitive HDTV camera tube is newly developed which adopts amorphous Se photoconductive target utilizing avalanche multiplication effect. By combining this target with high performance 1-inch all electrostatic electron optics successfully, very high sensitivity(20times as sensitive as standard Saticon tube) and, at the same time, high resolution(amplitude response at 800 TV lines is 35%) are achieved in new tube. In 20 times sensitive mode. S/N ratio is about 40 dB and the quality of picture satisfies the demands in HDTV use.
Process technologies were studied for three dimensional integration of compound semiconductors on Si. The device characteristics of GaAs MESFETs and InGaP LEDs on Si were examined for the purpose. Three dimensional structure of an InGaP LED stacked on a GaAs MESFET was fabricated on a Si substrate as an application of a newly developed SOI method to opto-electoronic integration. For further integration, a thermally stable ohmic contact to GaAs was developed. The fabrication of the 5x7 InGaP LED matrix stacked on the driver GaAs MESFETs was also described.
Excitonic polaritons are observed in a waveguide with a single GaAs quantum well. Picosecond time-of-flight measurements reveal a drastic decrease in the group velocity of a light pulse transmitted through waveguide. it is also shown that refractive index change associated with polaritons reaches as large as 20 % (normalized value) under the electric field of 40 kV/cm. Such a large refractive index change leads to new opto-electronic devices using polariton interference.
There has been an increasing interest in vacuum microelectronics using micron-size field emitter arrays. We have fabricated triangle-shape and film-edge(comb-shape) lateral emitter arrays made of 0.3-μm-thick tungsten film. In the case of comb-shape array with a self-aligned gate, emission current of 120μA was obtained at gate voltage of 250V. In the paper, the principle of the field emission, comparison between emitters with various structure and preliminary experimental result for application to flat-panel displays are described.