Macro-effects of resputtering due to negative ion bombardment of growing thin films

Abstract

Bombardment of a growing thin film by negative ions can lead to changes in the film through the process of resputtering. Macro-effects of resputtering (effects on the film thickness) include a slowing of the film growth rate and, in some cases, a complete suppression of the film growth as well as an etching of the substrate materials. To study this result of resputtering, rf-diode sputtering was used to deposit BaTiO 3 films under a variety of conditions, varying deposition time, rf-power level, substrate-to-target distance, total gas pressure, and argon, oxygen, and hydrogen partial pressures. The effect resputtering had on the thickness was seen to be a result of the competition between deposition and etching of the thin film material. The relative influence of the various sputtering parameters and the effect each of these has on the thickness distribution were examined. It was found that the greatest influence was system geometry, followed by rf-power level. Various methods of controlling resputtering are discussed.

Effects of oxygen partial pressure on the preferential orientation and surface morphology of ITO films grown by RF magnetron sputtering

“…Concerning the surface morphology in the tilted SEM photographs shown in Fig. 3, a very rough surface was observed in the (400) Concerning the momentum transfer of oxygen, the resputtering effect has been studied in sputtering-assisted oxide thin film growth, in which negative oxygen ions are frequently formed [20][21][22][23][24][25][26]. Cuomo et al suggested that if the value of I − EA (I: ionization potential, EA: electron affinity) were less than 3.4 eV, they predicted a negative ion formation, and the presence of resputtering effects [22,23].…”

“…However, it is believed that the resputtering effect could not interpret every phenomenon which occurs in oxide films since discrepancies in experimental results often exist between films deposited with different materials and conditions. According to research by Kester et al [25], which is one of the most frequently cited regarding the resputtering effect, the film thickness decreased linearly as oxygen partial pressure increased. However, in the case of this study, the thicknesses of the films drastically decreased when a small amount of oxygen was added to the sputtering ambient, and they subsequently decreased slowly as the oxygen partial pressure increased (thickness change is Fig.…”

Effect of deposition parameters on the growth rate and dielectric properties of the Ba(SnxTi1−x)O3 thin films prepared by radio frequency magnetron sputtering

“…At a given rf power, the thermalizatoin region shifts toward the target by increasing O 2 partial pressure. 22 This result leads to the oxidation of the target 23,24 and possible resputtering of the film 25 and created the decreased deposition rate of the BS x T 1−x thin films.…”

Effect of rf power on the dielectric properties of bismuth magnesium niobium titanium thin films deposited by RF magnetron sputtering

“…The surface roughness increase abruptly as the rf power increases at high rf power. This phenomenon can be expressed by macro effect as follows [17]. The rf power provide kinetic energy to the sputter-ejected species for absorption on substrate, atom arrangement and crystallinity.…”