Embodiments described herein are directed to a thin film capacitor (TFC) for power delivery that is in situ in a package substrate and techniques of fabricating the TFC. In one example, the TFC includes a first electrode, a dielectric layer over the first electrode, and a second electrode over the dielectric layer. Each of the dielectric layer and the second electrode comprises an opening. Furthermore, the two openings are positioned over one another such that the openings expose a surface of the first electrode. In this example, a first vertical interconnect access (via) is positioned on the exposed surface of the first electrode and a second via is positioned on an exposed surface of the second electrode. The TFC can be positioned in or on a layer of the package substrate close to a component (e.g., a die, a die stack, etc.) on the package substrate that may require a decoupling capacitance.