The present invention is generally directed to various processes and systems for forming layers and coatings on substrates, such as semiconductor wafers and solar cells. In one embodiment, the process of the present invention is directed to forming a layer on a substrate from a liquid precursor. The liquid precursor is atomized and exposed to light energy. Besides light energy, the parent material may also be exposed to an electric field and/or to sonic energy. In an alternative embodiment of the present invention a stress measurement device monitors stress in the substrate as a layer is deposited on the substrate. This stress measurement information is then sent to a controller for automatically controlling the amount of energy, such as light energy being emitted onto the substrate.