Abstract: Described is a method for depositing from the vapor phase a chemical species into the form of a thin solid film material which overlays a substrate material. The deposition process consists of three steps: (1) synthesis of depositing species, (2) transport of said species from site of synthesis to a prepared substrate material, and (3) condensation and subsequent film growth. The transport step is achieved by admixing small concentrations of the depositing species into the flow of a high speed jet of an inert carrier gas. This jet impinges on the substrate's surface and thereby convects the depositing species to this surface where condensation occurs. Since the gas mixture is at fairly high pressure, the deposition is achieved in a simple flow apparatus rather than in the high vacuum systems required of other methods. Also this transport technique allows the chemical and/or physical phenomena utilized in the depositing species synthesis step to be isolated from the actual condensation reaction.