Photo-sensitivity of large area physical vapor deposited mono and bilayer MoS(2)

We present photosensitivity in large area physical vapour deposited mono and bi-layer MoS(2) films. Photo-voltaic effect was observed in single layer MoS(2) without any apparent rectifying junctions, making device fabrication straightforward. For bi-layers, no such effect was present, suggesting strong size effect in light-matter interaction. The photo-voltaic effect was observed to highly direction dependent in the film plane, which suggests that the oblique deposition configuration plays a key role in developing the rectifying potential gradient. To the best of our knowledge, this is the first report of any large area and transfer free MoS(2) photo device with performance comparable to their exfoliated counterparts.