This is to review the resent development of the topics about the lateral distribution of implanted ions. The theoretical way to know the 3-dimension) ion distribution is initially demonstrated. The shape of lateral distribution and the depth, at which the lateral spread is maximum, are discussed by taking account of 4th order moment of ranges. Next, the experi-mental method to check the theoretical prediction is presented, and the experimental data are compared with theoretical ones. Finally, as a practical example, the lateral spread of the proton isolation layer in GaAs is experimentally discussed. As results, it is concluded that the lateral spread of implanted light ions and of proton isolation layer is not negligible for the fabrication of devices of μm dimension.
The electrostatic spraying of liquids was investigated by using dc and ac voltages as a power supply under various experimental conditions. The relation between spraying modes and controlling factors, in particular, varieties of applied power supply was examined. Three typical spraying modes appeared as the voltage was increased in the case of positive dc power supply, while, in the negative dc case, one additional singular mode with strong corona discharge appeared at high voltages above 20kV. These modes were divided into domains in terms of voltage and mass flow rate. It is concluded that the positive do voltage is the most suitable power supply for liquid atomization in view of the fact that it gives droplets finer than negative dc or ac voltage. The general behaviour of liquid sprays observed in this experiment roughly coincide with those of the previous work.
Linearly polarized light becomes elliptically polarized when light is transmitted through optical glass under stress and if the direction of applied stress differs from the direction of polarization. Photo-elastic constants can be obtained from the relation between the stress and the refractive index variation by measuring the ratio of electric fields in the direction of the major axes of elliptical polarization. By measuring (1) the angle between the direction of polarization of the incident linearly polarized light and the major axes of elliptical polarization and (2) the intensity of electric fields in the direction of the major axes of elliptical polarization, both direct and transverse photo-elastic constants can be obtained by computing the refractive index variation in the direction of and also in the direction orthogonal to the applied force.
In this paper, the process leading to inception of surface discharge on organic insulating materials in atmosphere of fogs was investigated with particular attention on inception time. Fogs were formed by an ultrasonic vibration. Specimens used in this test were chroloplene-rubber (CPR), epoxy resin (EX), polycarbonate (PC), polystylene (PS) and phenolic paper laminate (KPL). In part, a piece of ceramic insulator was used. The mean radius of fogs formed by the ultrasonic vibration is about 4.5μm, and the size and frequency distribution of the fogs are the same as fogs formed by radiation cooling. With increased exposure to the fog, a large number of droplets are formed on the specimen due to mutual collision and combination among the droplets. A glow-like discharge initiates locally across a dry belt formed by Joule heat several 10 msec several sec after the droplets had bridged across the electrodes, the time depending upon, the applied voltage. The relation among specimens for the inception time of surface discharge is given by CPR_??_EX>PC_??_PS>KPL<Ceramic insulator. This tendency corresponds with that of the contact angle among specimens.
A level indicator which is capable of detecting the liquid helium level without influences of mist, convection, etc. is described. A level sensor consisting of a 4mm, outside diameter SUS pipe, sintered filter, cotton tube, and Ti-Nb-Mo wire together with an indicating device with relays for alarm and/or level control is developed for the present purpose. The results of performance tests show small heat dissipation (9.6_??_17.1mW/cm), reasonable accuracy (±2mm) and resolution (±1.5 mm), and good linearity (±1.2%). Moreover, the presence of magnetic field, mist, and strong convection caused by liquid transfer and fast vaporization have no observable influences on level detection.
The optimal conditions of the conductivity anisotropy ratio _??_ and the dielectric an-isotropyΔε were studied on DSM-type liquid crystal display devices. It was proved that when _??_ was mae as large as possible and Ac was between -0. 2 and -0.05 for parallel-aligned cell and about -0.2 for vertically-aligned cell, high contrast could be obtained at a low applied voltage. However, the do dependence of contrast in the vicinity of the optimal value of Δε became less significant with increasing _??_.