A theoretical determination of oscillator strengths for the cesium atom is proposed. The values obtained are compared with experimental results deduced from the emission spectra of a slightly ionized quiescent cesium plasma discharge.

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The current-voltage characteristics (I-V) of Au-n-type InP Schottky diodes and MIS Schottky diodes fabricated by multipolar plasma oxidation are measured at various temperatures in order to investigate the applicability of a newly proposed conductance technique. Experimental data are analysed on the basis of this technique relating the series resistance Rs and the ideality factor n to the conductance G=dI/dV, and leading also to the determination of the saturation current Is. The values obtained for the temperature coefficient of the Schottky barrier height alpha were -1.3*10-4 eV K-1 and 4.1*10-4 eV K-1, depending on the substrate, and the ideality factors were around 1.07. The Richardson plot ln(Is/T2) against (1/T) is well fitted to a straight line (T is the temperature). It is shown that, when some conditions discussed in the paper are fulfilled; the method can be applied to MIS Schottky diodes. In this case the apparent barrier height phi Bh increases linearly with increasing temperature and the electron tunnelling factor is estimated to be 16.

The properties of oxide grown on InP samples immersed in an oxygen plasma depend on the physical (pressure, discharge power) or geometrical (size and position of the electrodes and sample) parameters and the characteristics of the sample (surface states, temperature, biasing). An electrostatic probe is used to study the variation of the plasma parameters with the discharge power and sample biasing. The electrical properties of InP oxide are related to the plasma parameters. The effect of the energy of the particles impinging on the sample is discussed. The experimental study has been carried out under the following conditions: RF plasma, 13.56 MHz; pressure, 60 m Torr; sample temperature, 300 degrees C; distance between electrodes, 9.2 cm; duration of oxidation treatment, 30 min.

Experiments performed on solitons and shocks generated in a double-plasma device identify clearly the precursors in front of them as ballistic ions due to light impurity atoms present in the vacuum vessel. The low ionization potential of these impurities enhances greatly their relative abundance.