On the ion and neutral atom bombardment of the growth surface in magnetron plasma sputter deposition

Abstract

The energy distribution of positive argon ions bombarding the substrate during radiofrequency magnetron sputter deposition has been measured as a function of the argon pressure. The results are related to measurements of the plasma potential distribution and understood invoking the occurrence of resonant charge transfer reactions. This effectively lowers the ion bombardment energy and causes the bombardment of the growth surface with neutrals of a few eV kinetic energy in the pressure range of 0.1–1Pa.

Ion beam shaping of Au nanoparticles in silica: Particle size and concentration dependence

“…As gold has a poor wetting affinity with SiO 2 , it is not precisely clear how the oxide layer forms around a NP in the sputtering deposition process. Since the SiO 2 top film is deposited in the low adatom mobility, zone 1, growth mode 23 at a relatively low ion bombardment energy, 24 most likely voids are expected to form in the growing oxide near the lower half of the NP due to shadowing effects in the sputter deposition. Even though none of these voids were imaged during the TEM analysis ͓Fig.…”

Influence of plasma-generated negative oxygen ion impingement on magnetron sputtered amorphous SiO2 thin films during growth at low temperatures

“…Some relevant scientific issues regarding the influence of the plasma on the film growth are linked to (i) cathode poisoning and process instability, 10,11 (ii) changes in the momentum and kinetic energy of the sputtered particles when arriving at the film due to scattering processes on plasma particles, [12][13][14][15][16] and (iii) positive and negative ion impingement on the film surface during growth. [17][18][19][20][21] Cathode poisoning is an undesired effect that takes place when there is an excess of reactive gas in the deposition reactor. This poisoning alters the composition of the first monolayers of the sputter target, thus diminishing the sputtering rate and efficiency of the overall process.…”

On the argon and oxygen incorporation into SiOx through ion implantation during reactive plasma magnetron sputter deposition

“…3 also contains the results of experiments in which the x-value was varied by a decrease in the silicon growth rate at higher total (Ar) pressures [20]. An increase of the total pressure results in a decrease in the ion flux and a small decrease in the average ion kinetic energy [2]. Despite these variations, also this series shows the same variation with x-value as the other experiments do.…”

“…The only other relevant mechanism for incorporation of argon is therefore the implantation of Ar + , ionized in the plasma afterglow region. These ions have a kinetic energy in the range 30-50 eV [2], resulting in an implantation depth of 0.5-1 nm according to SRIM simulations [19].…”

“…In magnetron sputter deposition of thin films the growing film is continuously bombarded with inert gas ions and neutrals [1,2], and, to a lesser extent, with reactive gas ions and ionized sputtered atoms and molecules [3]. The energy of the impinging ions depends on the pressure and power, and is closely related to the plasma potential, which in our unbalanced RF magnetron setup, where the anode is grounded, amounts to several tens of volts [4,5].…”