High-k dielectric thin films are widely applied in energy conversion/storage and information storage devices such as Dynamic Random access Memory (DRAM), Multilayer Ceramic Capacitor (MLCC), thermoelectric devices, etc. Among them, perovskite thin films, for instance, strontium titanate (STO) and barium titanate (BTO) are known to have extremely superior dielectric properties. Atomic layer deposition (ALD), can deposit thin films through atomic layering producing uniform and conformal high-k thin films with precise thickness control. While relatively low crystallinity of film quality due to low deposition temperatures of ALD can develop practical issues, they can be overcome by employing additional processes such as thermal annealing, plasma treatment, and seed layering. ALD, STO and BTO thin films treated with these additional processes demonstrate more improved crystallinity and electrical properties. In this paper, the processes to enhance properties of ALD high-k thin films, BTO and STO films are reviewed. Perspectives into high quality ALD high-k thin films as well as current efforts to further improve the film quality are discussed.