A method of fabricating a thin film heater is described. The method includes providing a heating element supported on a surface of a flexible dielectric backing film; and attaching a layer of heat shrink film onto the surface of the dielectric backing film so as to at least partially enclose the heating element between the heat shrink film and the dielectric backing film. The method provides a much more precise and consistent method of assembling the heater assembly and improves the thermal properties and heat transfer to a heating chamber.
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