Study on the selenization behavior of a DC magnetron reactive sputtered molybdenum nitride layers

•Thick Mo nitrides were reactively sputtered and selenized at high temperature.•Amorphous Mo at a moderate N2 pressure transformed to γ-Mo2N after selenization.•Crystalline γ-Mo2N at a higher N2 pressure produced an undesirable (002) MoSe2.•Unlike pure Mo, the resistivity of MoN is lowered after selenization. Numerous strategies have been investigated in the field of thin film photovoltaic technology to minimize the thickness of the MoSe2 layer formation during high-temperature selenization. Herein, a phase of molybdenum nitride (γ-Mo2N) is developed to prevent the production of excessive MoSe2. The Mo layers were sputtered at various N2 partial pressures (PN2, 0–0.67 mT) and then selenized for 10 min at 460 °C in a rapid thermal process (RTP) unit. The selenized film prepared at PN2 of 0.26 mT exhibited controlled MoSe2 thickness of ∼100 nm along with preferable (100) and (110) orientations. At higher PN2 of 0.51 and 0.67 mT, the thickness of MoSe2 was increased and had (002) plane as preferred orientation, which are unfavorable conditions. As a result, a PN2 of 0.26 mT has the most potent inhibitory effect on MoSe2 growth and the generation of favorable (100) and (110) orientations.