The use of Highly Ionized Pulsed Plasmas for the Synthesis of Advanced Thin Films and Nanoparticles

Abstract

Pulsed plasma processes open up the possibility of using very high plasma densities and modulated deposition in the synthesis of thin films and nanoparticles. The high plasma densities lead to a high degree of ionization of the source material, which creates new possibilities for surface engineering. Ions can, in contrast to atoms, be easily controlled with regard to their energy and direction, which is beneficial for thin film growth. Furthermore, ions can also increase the trapping probability of material on nanoparticles growing in the gas phase. The pulsed sputter ejection of source material also has other consequences: the material in the plasma and the material arrival on the growth surface will fluctuate strongly resulting in high level of supersaturation during pulse-on time. In this paper, an overview of the generation and properties of highly ionized pulsed plasmas is given. In addition, the use and importance of these types of discharges in the fields of thin-film and nanoparticle growth are also summarized.

Carbon nanoparticles characteristics synthesized in pulsed radiofrequency discharge and their effect on surface hydrophobicity

“…The influence of the modulated signal on nanoparticle formation has previously been considered in several studies. [34,35] Verdeyen et al showed that the amount of dust formation in SiH 4 plasma with pulse modulation is much lower than in continuous plasma. [36] Lloret et al used modulated RF discharge for the deposition of thin films of amorphous silicon and found that the modulation frequency had a strong effect on the porosity and roughness of films, and explained it by the effects of modulation on the nanoparticles formed in the plasma.…”

Obtaining of carbon nanoparticles in pulsed modulated RF discharge plasma

“…Влияние модулированного сигнала на формирование наночастиц ранее рассматривались в нескольких исследованиях [23,24]. Verdeyen и др.…”

Tuning the size, composition and structure of Au and Co50Au50 nanoparticles by high-power impulse magnetron sputtering in gas-phase synthesis

“…Since the seminal work of Haberland's group [12,13], magnetron based ion cluster sources (ICS), also known as Gas Aggregation Sources have gained in popularity, essentially due to the fact that they are commercially available, relatively easy to use and that most of the produced NPs are charged, which allows their electrostatic manipulation for deflection of mass filtering for example. Several modifications of the original design have been reported in the literature including the use of hollow cathodes [14][15][16][17][18][19][20] and multiple cathodes [21][22][23][24][25]. They are mainly used in straight direct current (DC) and radio frequency (RF) modes, i.e.…”

“…The fact that the growth rates for thin films are more difficult to control in comparison to the DC mode [35] can explain the limited number of studies of NPs synthesis using HiPIMS. So far, the pulsed mode has been used to prepare TiO x , Cu [20,[26][27][28] and Ag [29] clusters and the HiPIMS mode for the growth of Cu and Ag ones [16,17,19,29,31]. In all these studies, pure single element sputtering targets were used and studies using alloyed targets, to the best of our knowledge, have not been reported so far.…”