Minimum cost method for forming high density passive capacitors for replacement of discrete board capacitors using a minimum cost 3D wafer-to-wafer modular integration scheme

Passive, high density, 3D IC capacitor stacks and methods that provide the integration of capacitors and integrated circuits in a wafer to wafer bonding process that provides for the integration of capacitors formed on one wafer, alone or with active devices, with one or more integrated circuits on one or more additional wafers that may be stacked in accordance with the process. Wafer to wafer bonding is preferably by thermo-compression, with grinding and chemical mechanical polishing being used to simply aspects of the process of fabrication. Various features and alternate embodiments are disclosed.