Epitaxial molybdenum oxycarbide thin films synthesized by inductively coupled radio-frequency plasma assisted magnetron sputtering

Cubic molybdenum oxycarbide films have been synthesized on SUS 304 stainless steel and MgO(110) substrates at a temperature of 673 K by an inductively coupled radio-frequency plasma assisted magnetron sputtering method. X-ray diffraction measurement revealed that films prepared on stainless steel under a condition of high negative bias were polycrystalline and strongly (110) orientated molybdenum oxycarbide (Mo(C,O)) and that films prepared on an MgO(110) substrate under a high negative bias of −450 V were epitaxially grown Mo(C,O). The films showed an electric resistivity of 3 μΩm at 300 K and superconductivity with a superconducting transition temperature lower than 2.9 K.