The research of our effort were to investigate a novel platform to realize semiconductor microcavity polaritons. In contrast to allprevious work, van der Waals heterostructures, based on two-dimensional atomically thin materials, served as the matter system thatis coupled to a semiconductor optical cavity. Atomically thin semiconductors support both quantum-dot ielocalized, 0D and two-dimensional 2D extended excitons that can be seamlessly integrated with nanophotonic devices. The largebinding energy exhibited by the 2d excitons in two-dimensional semiconductors allowed for stable room temperature excitonformation and the realization of novel polaritonic based optoelectronic devices. In this research program, we fabricated andcharacterized semiconductor optical cavities suitable to couple with excitons in atomically thinsemiconductors and their van der Waals heterostructures. We specifically observed the formation of charged exciton trion cavitypolaritons. These trion-polaritons exhibit anomalous dispersion and should allow for the formation of interesting quantum matterstates. We also observed indications of room temperature quantum coherence in the form of coherent valley polaritons.