NOVELTY - Process chamber comprises a substrate support assembly positioned below a substrate processing zone to support a substrate on the assembly, a metal filament assembly (130) comprising one or more metal filaments disposed between the substrate support assembly and a first source inlet, and a showerhead assembly (120) disposed between the metal filament assembly and the substrate support assembly. The first source inlet is configured to deliver a first source compound. The showerhead assembly comprises a dual-zone face plate having first channels and second channels.    USE - The process chamber is useful for processing a substrate (claimed), which is useful for the fabrication of a thin film device such as semiconductor devices, solar cells, thin film batteries, polymer devices, flexible photovoltaic devices, and flexible electronics.    ADVANTAGE - The hot wire chemical vapor deposition chamber simply and economically fabricates the thin film device at low deposition temperature with high throughput and improved quality and uniformity and without using plasma in an efficient manner.    DETAILED DESCRIPTION - Process chamber comprises a substrate support assembly positioned below a substrate processing zone to support a substrate on the assembly, a metal filament assembly (130) comprising one or more metal filaments disposed between the substrate support assembly and a first source inlet, and a showerhead assembly (120) disposed between the metal filament assembly and the substrate support assembly. The first source inlet is configured to deliver a first source compound. The showerhead assembly comprises: a dual-zone face plate having first channels and second channels; and a showerhead body comprising a fluid conduit that surrounds the dual-zone face plate to flow a second source compound in the fluid conduit and to deliver the second source compound from the showerhead body into the dual-zone face plate. The first source compound is delivered from the first source inlet to pass through the metal filament assembly and the first channels and form radicals of the first source compound in the substrate processing zone without forming any plasma. The second source compound passes through the second channels of the dual-zone face plate without contacting the first channels and without forming any radicals or plasma, and is delivered into the substrate processing zone to react with the radicals of the first source compound on a surface of the substrate. An INDEPENDENT CLAIM is included for a method of processing a substrate (106) within the process chamber, comprising delivering the first source compound into the process chamber, delivering a current to metal filaments disposed within the process chamber, flowing the first source compound through the metal filaments to generate radicals of the first source compound, passing the radicals of the first source compound through first channels within the face plate of the showerhead assembly, delivering the second source compound into the showerhead assembly inside the process chamber, flowing the second source compound through second channels within the face plate of the showerhead assembly without forming any radicals or any plasma and without contacting the radicals of the first source compound, and reacting the flow of the second source compound, which is delivered from the second channels, with the radicals of the first source compound which is delivered from the first channels in a substrate processing zone near a surface of the substrate.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a processing chamber.    Chamber body (102)    Chamber lid (104)    Substrate (106)    Showerhead assembly (120)    Metal filament assembly. (130)