A key feature of most TMDCs is the direct-to-indirect bandgap transition upon crystal growth from a truly two-dimensional monolayer to multilayers. Since direct optical transitions exhibit larger extinction coefficients and usually faster recombination times, it is generally assumed that TMDC monolayers are superior for photodetection in both, sensitivity and speed. Indeed, for the intrinsic photoresponse this holds true, as demonstrated e.g. for two terminal MoTe2 photodetectors with thicknesses of 2 nm to 35 nm and response times of 4 ps to almost 1 ns, respectively (Figure ). In addition to the effect of the direct-to-indirect bandgap transition, this finding could be rationalized further in terms of the quantum mechanical wave function model, predicting that bulk defects in MoTe2 have a much longer lifetimes than surface defects, which increases the intrinsic response time. For the extrinsic photoresponse however, additional factors must be considered, which may outcompete the intrinsic advantages of monolayers. These include the stronger total absorbance of multilayers (due to longer optical path lengths) and the concomitant increase in photocurrent as well as material-specific differences in the lifetimes of surface defects. For MoS2 for instance, monolayers exhibit three orders of magnitude longer extrinsic response times than multilayers of 10 nm thickness, presumably due to deep surface trap states, which become increasingly screened in the bulk. This behavior is also often referred to as persistent photocurrent, a feature that is quite prominent in MoS2 and severely limits the prospects of MoS2 monolayers as fast photodetectors. For WSe2 in contrast, we have recently shown that the extrinsic response time is much more robust against surface trap states. Here, the major speed limitation is the RC time, which scales with the photoresistance of the devices. Monolayers of TMDCs exhibit less total absorbance and, thus, fewer photoexcited charge carriers which leads to longer RC times. In principle, this disadvantage can be addressed by increasing the irradiance as we will detail below.