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Solar selective coatings of HfO_x/Mo/HfO₂ were deposited on copper (Cu) and stainless steel (SS) substrates using a magnetron sputtering system. The HfO_x and HfO₂ layers were deposited from the sputtering of Hf target in Ar+O₂ plasma using an asymmetric bipolar-pulsed direct current generator, whereas the Mo layer was deposited from the sputtering of Mo target in the Ar plasma. The optimized HfO_x/Mo/HfO₂ multilayer absorber on Cu substrate exhibited high solar absorptance (α=0.905–0.923) and low thermal emittance (ε_82°C=0.07–0.09). Similarly, on SS substrates the optimized coatings exhibited α and ε_82°C in the ranges of 0.902–0.917 and 0.15–0.17, respectively. The X-ray diffraction data showed that the HfO_x/Mo/HfO₂ coating consists of tetragonal and monoclinic phases of HfO₂, which was confirmed by micro-Raman spectroscopy data. The bonding structure of the HfO_x and the HfO₂ layers were …