The　large-scale　fabrication　of　high-performance　on-chip　micro-supercapacitors　(MSCs)　is　the　footstone　for　the　development　of　next-generation　miniaturized　electronic　devices.　In　practical　applications,　however,　MSCs　may　suffer　from　a　low　areal　energy　density　as　well　as　a　complicated　fabrication　strategy　that　is　incompatible　with　semiconductor　processing　technology.　Herein,　we　propose　a　scalable　fabrication　strategy　for　the　realization　of　a　silicon-based　three-dimensional　(3D)　all-solid-state　MSC　via　the　combination　of　semiconductor-based　electrode　processing,　chemical　vapor　deposition,　and　hydrothermal　growth.　The　individual　Si/C/MnO2　electrode　shows　a　maximum　specific　capacitance　of　223.74　mF　cm−2,　while　the　symmetric　electrodes　present　a　maximum　areal　energy　density　of　5.01　μWh　cm−2　at　the　scan　rate　of　1　mV　s−1.　The　full　3D　Si/C/MnO2　MSC　delivers　a　high　energy　density　of　2.62　μWh　cm−2,　at　a　power　density　of　117.82　μW　cm−2,　as　well　as　a　long　cycle　life　with　capacitance　retention　>92%　after　4000　cycles.　Our　proposed　method　enables　the　fabrication　of　3D　MSCs　based　on　a　thick　silicon　interdigitated　electrode　array,　holding　a　great　promise　for　the　development　of　3D　on-chip　microscale　energy　storage　devices.　©　2020　American　Chemical　Society