Diagnostics of inductively amplified magnetron discharges by optical emission, absorption spectroscopy, and Langmuir probe measurements

Abstract

A direct current (dc) magnetron discharge is coupled to an inductively induced radio frequency (rf) one. The rf part is obtained by means of an induction coil, placed parallel to the cathode. We study the effects of the rf induction coil on the properties of an argon discharge. The discharge is characterized experimentally by optical absorption and emission spectroscopy, Langmuir probe measurements and quartz microbalance. The results are analyzed in order to obtain information on the electrons (density, temperature), ions (density), and excited neutrals (density) as a function of the pressure, the dc and rf powers. It is found that the density of the cathode species is proportional to the dc power while the excitation or ionization degree of the species impinging the substrate is dependent on the rf power.

Measurement of ionic and neutral densities in amplified magnetron discharges by pulsed absorption spectroscopy

“…In the afterglow, at low electron density and temperature, the inverse case: n Ti 2 Ͼn Ti 3 Ͼn Ti 4 , is then observed. In the present experiments, the electrontitanium collision frequency increases with the electron density, thus with the rf power as shown by Vanderbecq et al 10 As a consequence, the temperature estimated, using the Boltzmann distribution of the Ti sublevels would give an excitation temperature T ex which results of collisions with both neutrals and electrons. The electron temperature more and more influences T ex as the rf power increases.…”

“…9 Maximum values of n e ϭ10 12 cm Ϫ3 have been measured in amplified magnetron discharge. 10 Then, the Stark broadening can be discarded in the linewidth calculations. The Zeeman broadening of spectral lines has also been checked.…”

Diagnostic of a RF (13.56MHz) Magnetron in Ar/CH₄ Discharge

“…The optical emission of Ar RF plasma, with a Ti target, is characterized by Ti, Ti + and Ar lines. This paper was focused on emission of argon line, as detailed in references [1,2,5,7,13] the Ar(4P) level emitting The intensity of the I Ar 750.3 nm line is mainly populated by electron impact excitation, and relax by radiative emission; its intensity (I Ar ) is given by the following equation:…”

“…To improve the growing film quality, the knowledge of the internal plasma parameters are of crucial importance. Many researches were carried out in the field of diagnostics of the radiofrequency (13.56 MHz) magnetron discharges with titanium targets and in the presence of methane gas precursor [3][4][5][6][7][8][9][10][11][12]. In this work we studied the self-bias voltage, because it behaves as the sputtering rate, and used optical emission spectroscopy (OES) for qualitative variation of the plasma electron density [13].…”

Reduction of effects of rarefaction in ionized physical vapour deposition discharges

“…The kinetic energy of the depositing ions can be controlled by setting the sample bias potential with respect to the plasma potential. By adjusting the ionized metal flux fraction (IMFF), for example by varying the power to the secondary plasma [10], the degree of directionality of the depositing flux can also be controlled.…”