The constraction of RF ion source is described and its working principles are descussed. Recent data from literature on mechanism of the ion beam extraction, beam energy distribu-tion and beam composition are reported as a systematic survey.
A new method is described for measuring the density in a vapor stream of any material that is deposited on a substrate by electron beam evaporation. For this purpose an L-gun was used, in which the cathode is grounded and both the anode and the crucible are supplied with positive high voltage. The vapor ions ionized by incident electron beam and its secondary electrons were measured atvarious evaporation rates. From this experimental result it is found that the evaporation rate of a given material is approximately proportional to the ion current. A current integrator can be utilized for the control of film thickness. Sensitivities of the order of Å per second or lower have been obtained.
A technique for measuring ultrasonic light diffraction spectra is proposed. Frequency of the light diffracted by ultrasonic waves is shifted in the first spectral order by that of ultrasonic waves. By superposing a reference coherent light on the diffracted light, the resultant light having the same beat frequency as the frequency of the ultrasonic waves can be obtained. Photoelectric currents gained by scanning the focal plane are recorded through the amplifier tuned to the frequency of ultrasonic waves. The ultrasonic velocity and absorption in media are obtained by analyzing the spectra. A technique for measuring thevelocity of ultrasonic waves in media by utilizing the information included in the phase term of the heterodyne signal is also described. The optical arrangement has been so constructed as to eliminate several sources of errors, such as thedrift of output signals due to the absorption of the ultrasonic energy in- media, and the fluctuation of the output power of the gas laser used as the coherent light source. Some results for water, glycerol and polyethylene glycol are shownat the frequency of 2MHz. The accuracy of 0.5% is obtained for the velocity in water.
A new type of piezoelectric effect has been found in certain elongated and polarized films of polymers, viz. poly (vinylidene fluoride), poly (vinylfluoride), poly (vinyl chloride) and poly-carbonate. The newly found piezoelectric polymers possess an mm 2 symmetry and piezoelectric constants d31, d32, d33, d15 and d24 where the z-axis is assigned normal to film surface and the x-axis in the direction of elongation. Piezoelectricity appears in the above polymer films after the following treatment. The films were stretched a few times of the original length at softing temperatures. A static electric field (about 300 kV/cm) was applied to the films along their thickness and the temperature was raised gradually to 60_??_90°C and then slowly cooled. The largest value of g31, and d31 found in poly (vinylidene fluoride) film was about 150 millivolt/gram and 20×10-8 cgs. esu. The spontaneous polarization in the piezoelectric poly (vinylidene fluoride) film was estimated to be about 2×10-6 Coulomb/cm2.
This report describes a procedure for the corr-ection of observed Bragg angles, when a misali-gnment exists between diffractometer and x-ray focus. It consists of, recording directly the incide-nt x-ray beam on the diffractometer, reading out its misalignment on the 2θ-scale of the diffracto-meter, and then making an estimate of correction of observed Bragg angles. A formula for the correction is given, which was verified by its application to Debye-Scherrerlines of Si powders.