No abstract

No abstract

Hydrogenated amorphous silicon (a-Si: H) films deposited by RF sputtering and doped with nitrogen have been found to have high dark resistivity (1013 Ω·cm) and high photoconductivity at a low field. The Fermi level is shifted by 0.2 eV toward the conduction band, compared with undoped film. The spectral response of this film covers the visible region well and a peak quantum efficiency of 1.0 has been obtained at a wavelength of 500 nm. The γ-value of the film is nearly equal to unity for visible radiation. Rise and fall time constants are shorter than 500 µs for a pulsed radiation of 550 nm emitted from an LED. We have found that nitrogen doped n-type a-Si: H films are quite suitable as a photoconductive material for a solid state color imager.

No abstract

It is not so long until HDTV broadcasting starts, and HDTV systems will be required more and more in regions of industrial and medical imaging fields.We have developed two types of 2/3-inch NP (stands for Mixed Field; same as MS Magnetic focus Static deflection) Chalnicon (Cadmium-Selenide photoconductive target) for HDTV systems.One of them, the type No. of N4272, is suitable for three-tube colour camera, black and white camera. And another one, the type No. of N4l82, is useful for radiation resistant use. ( lO Ren/h).Both N4272 and N4182 have such excellent features as high sensitivity (N4272: 0.16 pA/lx, N4l82: 0.15 pA/lx) and high resolution (1,150 TV Lines) which are good enough for required specifications for HDTV imaging devices.In addition to the features mentioned above, it is remarkable that maximum operating temperature of N4l82 is 185 °F. So that it is possible to use it for imaging under such a bad condition as high radiation and high temperature circumstances experienced for instance in the nuclear power plant.