Capacitor structure and circuit facilitating increased frequency stability of integrated circuits

In a monolithic integrated circuit structure having a plurality of diffused heavily doped isolation regions of a first conductivity type to isolate epitaxial islands of a second conductivity type, a monolithic capacitor structure, the improvement comprising:

• a first region of a second conductivity type, said first region being diffused into at least one of the plurality of isolation regions and forming a PN junction therewith, the outwardly facing surface of said first region being substantially equal in surface area to the surface area of the other of the plurality of isolation regions and being a portion of the surface of the monolithic integrated circuit;
• a layer of dielectric material, said dielectric material being grown over a main portion of said outwardly facing surface of said first region;
• a first layer of metallization, said first layer of metallization being contiguous with the outwardly facing surface of said layer of dielectric material for forming a first plate of the capacitor;
• and
• said first region being a second plate of the capacitor such that the monolithic capacitor structure thus formed in the isolation region of the monolithic circuit structure requires minimum useful area of the monolithic integrated circuit to be utilized in construction thereof, the plurality of isolation regions being otherwise required to provide isolation in the operation of the monolithic integrated circuit.