A thin film electronic device fabrication process includes providing an electronic device on a substrate, a first reactant gaseous material, a second reactant gaseous material, an inert gaseous material; and a delivery head through which the reactant gaseous materials and the inert gaseous material are simultaneously directed toward the electronic device and the substrate. One or more of the reactant gaseous materials and the inert gaseous material flows through the delivery head. The flow of the one or more of the reactant gaseous materials and the inert gaseous material generates a pressure to create a gas fluid bearing that maintains a substantially uniform distance between the delivery head and the substrate. Relative motion between the delivery head and the substrate causes the second reactant gaseous material to react with at least a portion of the electronic device and the substrate that has been treated with the first reactant gaseous material.