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Abstract. In this contribution we aim at presenting the overview of the work that has been done in expanding the applicability of the probe method to low-temperature plasma at the pressure range when the collisions of charged particles with neutrals start to be important (we call this pressure range medium pressures) and to plasma under the influence of the weak-to-medium magnetic field that is commonly used in plasma enhanced technologies. Most of the discussion is devoted to simple case of a plasma consisting of electrons and of one kind of positive ions. Our review also mostly concerns the cylindrical Langmuir probe. The first part of the article is devoted to discussion on the influence of the positive-ion-neutral collisions on the interpretation of the ion current part of the probe characteristic in order to get the true value of the plasma number density. In the second part one of the theories that take account of this effect is used to assess the influence of the weak magnetic field to the interpretation of the probe data. Finally we discuss the anisotropy of the electron velocity distribution function due to the effect of the magnetic field. The discussion is supported by the new experimental data.

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A simple model is developed to explain the measured temperature dependence of the growth rate of polymerfilms in a C,H,-Ne-glow discharge.The negative ARREENIus-behaviour obtained -that means a decreasing growth rate with increasing temperature -is determined by an adsorption-desorption-equilibrium of the monomer particles on the surface.From the fitting of the temperature behaviour experimentally obtained by probe measurements some characteristic parameters (activation energy, residence time) were calculated by means of the model.

Measuring the second derivatives of electron retarded current characteristics of a plane probe at different angle positions, the coefficients f*i(ε) of the velocity distribution function developed as a Legendre polynomial are determined for the anisotropic plasma of a hollow cathode arc discharge. The integral values deduced from this for the electron concentration ne and the mean electron energy ε̄, as well as the drift velocity vd, show only a limited dependence on the number of angle positions used for measurement. Even for measurements at a single angle position (Druyvesteyn method), the values obtained for ne, ε̄, and vd differ by less than 10% from the corresponding values measured with the multiposition method, so long as vdrift ≤ vthermal. On the contrary, the shape of f*i(ε), like the angle dependence f*(θ)ε=const, is clearly affected by the number of angle positions used. A Maxwell distribution superimposed by a group of directed fast electrons proves to be a sufficient model for the plasma investigated here.