Magnetron sputtering is used as a plasma processing technique to deposit very thin films onto a substrates for a wide variety of commercial manufacturing and scientific purposes in areas such as optics, electronics and packaging. Researchers need to simulate magnetron sputtering systems under different plasma characteristics, applied magnetic fields and geometry to obtain erosion profiles of the target material to allow for optimization of existing magnetic designs and creation of new magnetic designs with minimal risks, testing, and cost.
LG researchers used VSim to simulate magnetron sputtering for comparison to their large scale plasma sputtering erosion experiments for glass display plates. They measured the absorbed current pattern on the sputter target, which is believed to correlate with the target erosion pattern. VSim was then used to do the same measurement. Figure 1 shows VSim results which closely match their measured sputtering patterns. The knowledge gained from doing these simulations was applied to create better designs in future LG experiments.
As a particle-in-cell code, supplemented by its multi-physics library TxPhysics, VSim is capable of self-consistent charged particle simulations with electrostatic, ionization and particle interactions, which are vital to a successful simulation of magnetron sputtering. Its well scaled parallel computation capability enables VSim to carry these simulations out to ion crossing time scales and obtain realistic sputtering results which would otherwise be impossible on a similar serial code.
"VSim was an essential tool for us in our modeling of magnetron sputtering. Thanks to the vast array of capabilities available through VSim including both physics and its parallel computation, we were able to accurately predict the erosion profiles from our current designs and VSim continues to allow us to optimize our designs for the future. The support staff at Tech-X was also extremely helpful during the initial set-up and modeling process.” – Geejo Lee, Process CI Team Manager, LG Display Co., LTD.
Figure 1: The planar magnetron sputtering system simulated
by VORPAL (top). VORPAL results showing the spatial distribution
of the sputtered copper atoms (bottom). Based on these results,
the measured erosion shape of the sputtering pattern is shown
(middle right) which closely matches their measured profiles.