Modelling of Multi-Ion-Beam Reactive Cosputtering for Metal Oxide Thin Films
- PDF / 349,150 Bytes
- 6 Pages / 414.72 x 648 pts Page_size
- 55 Downloads / 205 Views
ABSTRACT Very recently a new technique named multi-ion-bcham reactive cosputtering (MIBRECS) was developed for preparing multi-component metal oxide thin films. Epitaxial or highly oriented (Pb, La) TiO3 thin films sputtered from pure metals of lead, titanium and lathanium were deposited by using this technique. In order to consummate the technique and to study the mechanism of reactive cosputtering, a general model of multi-ion-beam reactive cosputtering was proposed for the first time based on the well-known gas kinetics under stable sputtering circumstances, and a computer numerical simulation of the model was carried out with the parameters adopted in our experiments. The relationships among the sputtering ratioes of the targets, and the coverage ratioes of simple substances and oxides of the target metals on substrate surface with the total reactive gas flux and the densities of the sputtering ion beam were obtained respectively, and the hysteresis effect of the characteristic of reactive sputtering and the interactions during multi-ion-beam reactive cosputtering processes were also obtained. The numerical simulation results are at least qualitively in agreement with the experiments.
INTRODUCTION Reactive sputtering is a very useful technique for fabricating oxide and other compound thin films. It is widely accepted that the sputtering rate, deposition rate, and other sputtering courses are strongly dependent on the processing conditions in reactive sputtering. Because reactive sputtering is a complex nonlinear process and often exhibits hysteresis effects, it is difficult to realize controllable reproduction. In order to study the mechanism of reactive sputtering, several models have been suggested"-"'. The models in Reference 11-83 were used for DC or RF magnetron sputtering, and the model in Reference(91 was used for single ion beam reactive sputtering. Considering the distinct advantages of ion beam sputtering (IBS) over other sputtering processes and the need for seperately controlling each element of multi-component oxide thin films, we have recently developed a new sputtering technique named multi-ion-beam reactive cosputtering (MIBRECS), and established a related apparatusCl°o"'. Epitaxial or highly oriented PbTiO3 (PT) and La-modified PbTiO 3 (PLT) thin films were deposited from pure metals of Pb, La, and Ti by using this technique"1 '- . In order to consummate this technique and to study the mechanism of film growth by using reactive cosputtering, a general model of MIBRECS for metal oxide thin films was proposed based on well-known gas kinetics under stable sputtering circumstances, and a computer numerical simulation of the model was carried out with the parameters adopted in our experiments. In this paper, the fundamental and the computer numerical simulation of the model are reported.
FOUNDAMENTAL OF THE MODEL The schematic illustration of the MIBRECS system we developed is shown in Figure 1, in which T,, T 2 , and T3 are metal targets, IS,, IS 2 , and IS3 are focused ion sources for sputtering T
Data Loading...
