Pulsed laser deposition of oxides: Why the optimum rate is about 1 Å per pulse

An adiabatic thermalization model is developed to describe a typical pulsed laser deposition (PLD) process. The interaction of atoms in the plume, ejected from the target, with those of the background gas (e.g., oxygen) is specifically considered. The model gives a physical definition of the “plume range,” which depends on the particular PLD system, and calculates the range values. One prediction is that when the target-to-substrate distance is optimized, the deposition rate exhibits an extremely weak dependence on pulse intensity and will always be about 1 Å per pulse.