Enhancement of near-infrared detectability from InGaZnO thin film transistor with MoS light absorbing layer.

We report an enhancement of near-infrared (NIR) detectability from amorphous InGaZnO (α-IGZO) thin film transistor in conjunction with randomly distributed molybdenum disulfide (MoS) flakes. The electrical characteristics of the α-IGZO grown by radio-frequency magnetron sputtering exhibit high effective mobility exceeding 15 cm V s and current on/off ratio up to 10. By taking advantages of the high quality α-IGZO and MoS light absorbing layer, photodetection spectra are able to extend from ultra-violet to NIR range. The α-IGZO channel detector capped by MoS show a photo-responsivity of approximately 14.9 mA W at 1100 nm wavelength, which is five times higher than of the α-IGZO device without MoS layer.