The development of rare earth (RE) Ba2Cu3Oy (REBCO) coated conductors has been carried out by many groups. The critical current density (Jc) in high magnetic fields needs to be improved for superconducting applications. We have fabricated BaHfO3 (BHO)-doped SmBa2Cu3Oy films on ion beam-assisted deposition (IBAD)-MgO substrates using pulsed laser deposition (PLD). In this study, we introduce a seed layer technique. As a result, the appropriate growth temperature (Ts) is expanded to higher temperature range without BaCeO3 outgrowth around the interface of the SmBCO and CeO2 cap-layer. We were able to control the configurations of the BHO nanorods within the SmBCO films as compared to the conventional PLD method. The SmBCO + BHO (1.4 vol.%) films, which were fabricated at a Tsupper of 900ºC, showed that the Jc in the magnetic field (B // c) was improved as compared to pure-SmBCO films. Furthermore, the global pinning force density reached 21 GN/m-3 at 77 K in B = 2 T.