Abstract: The morphology of hydrogenated amorphous silicon (a-Si: H) films grown by plasma enhanced chemical vapor deposition (PECVD) is studied. Nonuniformly distributed bubble defects are formed during the process of a-Si: H films deposited on crystalline silicon substrate. The SiNx/a-Si alternative layers are deposited on the as-prepared a-Si: H film, a perfect dome-shaped multi-shell microstructure was formed at the site of the blister defect, and no distinct structural collapse was observed. Three unique characters of the self-formed dome-shape microstructure are concluded, and the potential applications of the proposed self-formed dome-shape microstructure in nanophotonics and MEMS are also pointed out.