For X-ray reflective optics that work based on the concept of total external reflection, coating the reflector surface with high-density film is a common idea to enhance performance. Atomic layer deposition (ALD) has been proven to be a promising way to coat the reflector surface with a large curvature, even the inner surface of an X-ray capillary. In this paper,
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and iridium films were prepared on flat silicon and glass substrates via ALD, and X-ray reflectivity (XRR) was used as a main tool to investigate the effect of film properties on the total reflection performance.