A graphite heater and method of forming a graphite heater comprising a
graphite body configured to form an electrical heating circuit for at
least one heating zone through the graphite encapsulated in a continuous
overcoat layer comprising at least one of a nitride, carbide,
carbonitride or oxynitride of elements selected from a group consisting
of B, Al, Si, Ga, refractory hard metals, transition metals, and rare
earth metals, or complexes and/or combinations thereof, wherein prior to
being configured to form the electrical heating circuit path, the
graphite body is coated with a layer comprising at least one of a
nitride, carbide, carbonitride or oxynitride of elements selected from a
group consisting of B, Al, Si, Ga, refractory hard metals, transition
metals, and rare earth metals, or complexes and/or combinations thereof.