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The conditions for the formation of a fully atomized laser-ablated plume using subpicosecond laser pulses have been studied theoretically and implemented experimentally. It is shown that the low-intensity wings, which generally exist in the spatial distribution of laser intensity in the focal plane and can contain a substantial part of the incident laser energy, are responsible for low-threshold phase transformations of the target and this is the major source of particulates in the ablated plume. By truncating these wings with a simple aperture and positioning the target in the image plane of that aperture, particulates can be eliminated from the plume. This is demonstrated in experiments on deposition of Si films using the truncated beam in combination with the proper choice of laser fluence. This results in an almost totally atomized plume and consequently in droplet-free deposition of thin films. © 2004 American Institute of Physics.