Since Graphene was discovered in 2004, two-dimensional (2D) materials have established themselves as one of the most promising materials for next generation electronics and optoelectronics. Despite graphene’s exceptional electron mobility, its absence of a naturally occurring band gap restricts its applicability in optical and digital electronics. While on the other hand, MoS2 is an indirect semiconductor in its bulk form which transitions into a direct band gap material in the monolayer limit. It is reported to have a high current on/off ratio of 108, and room temperature mobility of few hundreds of cm2/Vs. Stable individual layers, without any dangling bonds and a breaking strength comparable to that of steel, support the expectation that this material will compliment graphene in future devices. However, scalable fabrication of 2D materials-based devices with consistent characteristics remains a significant impediment in the field. This dissertation establishes a simple, deterministic and scalable method of 2D material based device fabrication which is compatible with silicon processing. It is based on concurrent growth and formation of electrical contact between bulk metal features and the mono-to-few layer semiconducting channel grown in between. In addition to producing high-quality material, it opens a completely new field of hetero-structured devices with as grown electrical contacts. Detailed optical and electrical characteristics of MoS2 ¬based photodetectors grown using this method show high responsivity (~1 A/W) even at a low drain-source voltage (VDS) of 1.5 V and a maximum responsivity of up to 15 A/W when VDS = 4 V with an applied gate voltage of 8 V. The response time of these devices is found to be on the order of 1 µs, an order of magnitude faster than previous reports based on devices fabricated using conventional method. Preliminary results on calculation of Schottky barrier height (SBH) and related future works are presented.