Generalized Keller-Simmons formula for nonisothermal plasma-assisted sputtering depositions

摘要

A general description of the relation between the sputtering rate and the deposition rate in plasma-assisted sputtering deposition has been developed. The equation derived yields the so-called Keller-Simmons [IBM J. Res. Dev. 23, 24 (1979)] formula in the limit of zero thermal gradients in the deposition system. It is shown that the Keller-Simmons formula can still be applied to fit the experimental results if the characteristic pressure-distance product, p_0L_0, is related to the temperature of the sputter cathode and the growing film. Using this relation, it is found that the variations in the values for p_0L_0 for different experimental conditions agree with the thus far not well understood experimental trends reported in the literature.