We report the growth of potassium-doped BaFe 2 As 2 thin films, where the major charge carriers are holes, on Al 2 O 3 (0001) and LaAlO 3 (001) substrates by using an ex-situ pulsed laser deposition technique. The measured T c 's are 40 and 39 K for the films grown on Al 2 O 3 and LaAlO 3 , respectively and diamagnetism indicates that the films have good bulk superconducting properties below 36 and 30 K, respectively. The X-ray diffraction patterns for both films indicated a preferred c-axis orientation, regardless of the substrate structures of LaAlO 3 and Al 2 O 3 . The upper critical field at zero temperature was estimated to be about 155 T.

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