  We demonstrate a deterministic Purcell-enhanced single-photon source realized
by integrating an atomically thin WSe$_{2}$ layer with a circular Bragg grating
cavity. The cavity significantly enhances the photoluminescence from the
atomically thin layer, and supports single-photon generation with
$g^{(2)}(0)<0.25$. We observe a consistent increase of the spontaneous emission
rate for WSe$_{2}$ emitters located in the center of the Bragg grating cavity.
These WSe$_{2}$ emitters are self-aligned and deterministically coupled to such
a broadband cavity, configuring a new generation of deterministic single-photon
sources, characterized by their simple and low-cost production and intrinsic
scalability.
