The photocurrent multiplication of hydrogenated amorphous silicon p-i-n photodiodes was observed in photodiodes that were fabricated on a heavily doped n-type silicon substrate using a high-vacuum plasma enhanced chemical vapor deposition (PECVD) system. By using this improved PECVD system , the breakdown field of the photodiode was changed from 3 × 10^5V/cm to 1 × 10^6V/cm. It seems that the reason for this increase of the breakdown field was a decrease of localized states in the forbidden gap that was produced by contaminates. The a-Si:H p-i-n photodiodes with low residual stress were fabricated on Si substrates, and the photocurrent multiplication was observed in these photodiodes. The wavelength dependence of incident light and the a-Si:H thickness dependence of intrinsic layer were found and these characteristics were explained by the avalanche multiplication of photogenerated electrons.
In this paper, an architecture of imagers which execute motion estimation on the focal plane is proposed. Since the motion estimation needs quite heavy processing, the proposed parallel architecture can effectively reduce the total processing time and circuit complexity. A kind of single pixel matching is employed in this algorithm. Validity of this algorithm is confirmed by simulations. We also propose one of its component circuits: MOS resistor with segmentation switch.
The weak string filter smoothes out noise involved in a given data while it detects step edges inherent to the original noise free data. This paper proposes how to weak string filter can be implemented by νMOS transistors. Several experimental results are given.
For the purpose of realizing the very fine barrier electrode ac plasma displays, we fabricated the testing panels with a cell pitch of 0.5mm by sandblasting method. we investigated the materials and fabricating method. As a result, we were able to obtain the excellent results of very high luminance of 720 cd/m^2 and luminous efficiency of 0.5 lm/w for the panel with a cell pitch of 0.5mm.
Mgo protecting layer for ac-PDPs was prepared by rf magnetron sputtering method with and measured aging characteristics of testing panel sputtered Mgo is excellent in point of low sustaining voltage and stability of sustaining voltage. we analyzed sputtered Mgo by x-ray diffraction and scanning electron microscope.
plasma display panels, we call them PDPs, are one of the flat panel displays, which make use of discharge phenomenon for indication. color indication panels make use of photluminescence that was excited and emitted a fluorescent substance by ultra-violet rays. Therefore, informations that were connected With ultraviolet rays are important for higher brightness and luminous efficiency that are problems for color panels utility. In this experiment, Ne+Xe gas was used for working gas and we measured about spectra emitted from the states concerned with ultraviolet rays emission of 1470A.
In the present paper, we fabricated the field emitter arrays(FEAs) made of n-type silicon coverd with the metal by photolithography. We measured the energy distribution of the field emitted electrons by an ac retarding field method. We culculated the theoretical energy distribution by giving temperature, work function of emitter material,and electlical field. We found the value of field from slope of Fowler--Nordheim plot.
Forming processes of ZnS:TbF_3 thin films and ZnS thin films were analyzed by TEM. Accordingly the following results are obtained, (1) Forming processes of ZnS and ZnS:TbF_3 were investigated. (2) Fusion of islands which observed in early forming processes changes orientation of ZnS crystal . (3)Tb atoms or particles disturb recrystalization of ZnS
Market place of high resolution, wide screen color CRTs for home use TVs is expected to increase drastically. In these tubes, moire patterns generated by an interaction between raster scan beams and shadow mask apertures damage picture quality. A computer simulation of the raster moire patterns which appear on slotted mask CRTs are performed, taking into consideration the low pass filter characteristics and light difference threshold characteristics of human eyes. The simulated moire patterns coincided well with the visual observations. Also moire contrast was evaluate to find perceptivity of the moire patterns.
The decay time of green phosphors and the life of blue phosphors for full-color PDPs have been investigated. Optimization of Mn content of Zn_2SiO_4Mn^<2+> to 2.6 (weight%) caused the decay time (1/e) of 3.9ms, which is sufficient for practical use, and other characteristics is also better than conventional phosphors. Luminance of conventional blue phosphor (BaMgAl_<14>O_<23>:Eu^<2+>) decreased with discharging time, the emission spectra also changed. Improved phosphor (BaMgAl_<10>O_<17>Eu^<2+>) dose not change the emission spectra, and the life is longer than conventional phosphor by from two to three times.
An improved fluorescent lamp suitable for backlighting LCD has been realized by developing a Cs impregnated sintered metal cathode.Luminance of 22,000cd/m^2 and lifetime of 20,000 hours are obtained with 5.8 mm diameter lamp.