Photonic circuits, operating at hundreds of THz frequencies, have been suggested as a possible solution to overcome the GHz-limited processing and clock-synchronization speeds in nowadays electronic circuits, however, at the prize of rather bulky, diffraction-limited feature sizes. To realize photonic elements matching the lateral sizes of state-of-the-art electronics (<50 𝑛𝑛𝑛𝑛), the one and maybe only approach is the use of excitations in nano-engineered metals – a rapidly growing research field known as nano-plasmonics. We will integrate lithographically defined, optically active, and electrically controllable nanoscale components into state-of-the-art silicon photodetectors. The optically active parts are two-dimensional, atomically thin semiconductor crystals which will allow us to generate, control, and detect optical signals on a single chip. For the controlled detection, the two-dimensional crystals are embedded as an electrode of an industrial photodiode. Plasmonic circuits shall guide and distribute the signals between the on-chip generation and detection on sub-wavelength scale channels. We envision the potential of two-dimensional crystals and plasmonic circuits for novel optoelectronic applications in industrial silicon electronics with superior performance according to high operating speeds, low driving voltages, low power consumption, and compact sizes.