Fig. 4

Raman intensity ratio of LO/E2g as a function of the H2S annealing temperature (a) without and (b) with the following Ar annealing at 1100 °C for 10 min. MoOx films with x = 2.89 were used, with H2S annealing conducted under 100 Pa and 50 kPa for 10 min as a common condition. Cross-sectional TEM images of MoOx films with x = 2.89 after H2S annealing at 600 °C under 50 kPa for 10 min (c) without and (d) with subsequent Ar annealing at 1100 °C for 10 min.