Fabrication processes and experimental validation of a planar PV power system with monolithically embedded power converters

This paper summarizes the research outcome intended to identify the most suitable device architecture and its implementation for cell-level power conversion in a photovoltaic (PV) system. The fabrication process to accommodate the power conditioning unit with the PV cells using the same process run have been presented in this paper. Using this method, the entire converter can be embedded with the PV cells producing AC power directly from the solar cell strings. The initial phase of this project simulated various circuit components in the CMOS process, and the project outcome has been summarized in a previous publication by the authors. This paper presents the experimental results of the proposed process, and a simple chopper circuit has been constructed using the embedded MOSFETs and the PV cells. The circuit has been experimentally characterized, along with components. In addition to the process-related challenges and issues, this paper explains the justification of this integration by achieving higher reliability, portability and complete modular construction for PV-based energy harvesting units. To the knowledge of the authors, no attempt has been made to fabricate power converter components with PV cells in the same process run.