The secondary electron (including Auger electron) emission has received renewed interest as a powerful approach to surface analysis and as a signal source in the scanning electron microscopy (SEM) and Auger electron spectroscopy (AES). In the SEM the secondary elec-trons produced by primary electrons play a predominant role as the signal. In the AES, on the other hand, Auger electrons produced by primary electrons should be separated from those by backscattered electrons for quantitative interpretation. Almost all works on the secondary electron emission in the reviews or texts published so far have, however, described the total secondary electron yield without distinguishing whether it is due to primary electrons or backscattered electrons. Recently there have been published theoretical and experimental studies which enable us to understand the mechanism of secondary electron emission to some extent. In the view point of solid state physics some of these experiments have revealed fine structures due to interband transitions in the secondary electron energy spectra. Another fine structures have also been found in the angular distribution of secondary electrons as well as in the secondary yield vs. angle of incidence in single crystals, and the latter structures have been well explained by the dynamical theory of electron diffraction. An approach to determine the surface potential for semiconductor materials is also briefly introduced.
The electrical and structual properties of thin films of hafnium and hafnium nitride were studied. They were deposited on a glass substrate by DC sputtering under the substrate potential Vs. The properties of these films were investigated as a function of the partial nitrogen pre-ssure in the sputtering atmosphere. At low partial nitrogen pressure, hcp Hf was formed, and the specific resistivity increased as the nitrogen pressure was increased. At an interme-diate partial nitrogen pressure, the specific resistivity and the temperature coefficient of resistance had constant values over a certain range of partial nitrogen pressure, which seems to corres-pond to the plateau observed in Ta-N system. These films were a mixture of Hf, HfN and another unknown phase. At high partial nitrogen pressure, HfN single phase was formed. The substrate potential affected the electrical properties of films at high partial nitrogen pressure.
In this experiment, we examined the change of the minority carrier life time in annealed as-grown silicon. Values of the minority carrier life time were obtained from the photocon-ductive decay measurements using microwave techniques. In n-type floating zone silicon (dislocation free), the minority carrier life time increases below the annealing temperature of 300°C and decreases abruptly between 300°C and 500°C, and, moreover, effects of swirl were not observed. On the other hand, the minority carrier life time in n-type pulled silicon (dislocation free) did not charge below 500°C annealing. Defect formation energy in floating zone n-type silicon (dislocation free), in pulled n-type silicon (dislocation free) and in floating zone n-type silicon (with dislocation) were 0.76 eV, 0.86 eV and 0.56 eV, respectively. Al-though the defect energy level in dislocation-containing silicon did not change during the an-nealing, the level depth in dislocation free silicon increases as the annealing temperature increases.
The viscometer of the lifting liquid type here reported is composed of two steel balls of different diameters, which are hung on the two arms of a balance. Both the hanging fibers are of equal diameter. The balls are immersed in the liquid to be examined, and the vessel of the liquid is drawn up with a desired constant velocity. In contrast with the viscometer of the lifting liquid type with a single ball previously reported, it is unnecessary to take into account the change of the length of fiber immersed in the liquid and the surface tension. With a constant drawing-up velocity the difference of the viscous drags acting on the two balls (ƒ1-ƒ2) is determined by maintaining the equilibrium of the balance. The coefficient of viscosity η can then be obtained by ƒ1-ƒ2=6πη (rl-r2)v, asauming Stokes' law of viscosity. The results show that the coefficients of viscosity thus calculated depend on the lifting velocity, and the limiting values corresponding to the zero lifting velocity coincide with the true values.
Transparent electrodes of indium tin oxide (In2-xSnxO3, ITO) with high conductivity, transparency, and adherence, were deposited on glass plates by rf sputtering. The character-istics, stability, and crystallization of the films depend mainly on the input power and substrate temperature during sputtering. The films in routine process have a resistivity of about 4×10-4 Ω-cm, and transmittance of above 80% at 550mμ. The ITO films are very stable, and no aging effect was observed. Adhesive strength between the films and the substrate glass exceeds 120kg/cm2, and feasibility for pattern formation of electrodes by ordinary etching process is ensured.
In scanned ultrasonic holographies, distorted holograms are recorded due to the synthetic scanning method in which the hologram is constructed by a synthesis of one-dimensional scannings of the receiver with the moving source (or object). In this paper a technique for the reconstruction from such distorted holograms is described. It is shown that an image is obtainable from the distorted hologram by the illumination of a tilted plane wave. However the shape of the image obtained is not similar to that of the original object. Therefore the image is observed in a plane which is not parallel to the hologram in order to get the proper image. The condition for obtaining the similarity is shown from a theoretical analysis. To verify these results, distorted holograms constructed by synthetic scanning using a 1MHz ultrasonic wave in water, were reconstructed according to the procedure described above with satisfactory results.
Al-doped CdS single crystals are grown by a sublimation method. An interesting crystal habit is observed in these crystals. Crystals grow along c axis direction in the early stage. Then the growth in this direction is suppressed and hexagonal shaped basal planes grow. The observation of the etching behavior of basal planes of these crystals shows that the upper surface is (0001) S surface and the lower surface is (0001)Cd surface.
A liquid-crystal cell is composed of SnO2-coated glass-plates rubbed with cotton cloth and a positive, dielectrically anisotropic nema-tic liquid-crystal. Transmission properties and the electrically induced birefringence of the cell vary symmetrically or unsymmetrically with the tilting angle between the cell and the direction of an incident light according as the rotating axis of the cell is parallel or perpendicular to the direction of rubbing, respectively. These properties are explained from the effect of rubbing and the rearrange-ment of the liquid-crystal molecules when a voltage is applied to the cell.