An exemplary method of depositing a layer of a material on an interior substrate surface of a complex geometry component includes the steps of providing the complex geometry component having an aperture defining an edge of the interior substrate surface of the complex geometry component, at least a portion of the interior substrate surface defining a first area not visible from the aperture, providing a heating element adjacent to the first area of the complex geometry component, energizing the heating element to raise a surface temperature of the first area and establish a thermal gradient between the first area and an adjacent area, and providing a vapor deposition apparatus configured to deposit the layer of material on the interior substrate surface corresponding to the first area of the complex geometry component.