| 摘要 |
An isolated shallow trench isolation portion is formed in a top semiconductor portion of a semiconductor-on-insulator substrate along with a shallow trench isolation structure. A trench in the shape of a ring is formed around a doped top semiconductor portion and filled with a conductive material such as doped polysilicon. The isolated shallow trench isolation portion and the portion of a buried insulator layer bounded by a ring of the conductive material are etched to form a cavity. A capacitor dielectric is formed on exposed semiconductor surfaces within the cavity and above the doped top semiconductor portion. A conductive material portion formed in the trench and above the doped top semiconductor portion constitutes an inner electrode of a capacitor, while the ring of the conductive material, the doped top semiconductor portion, and a portion of a handle substrate abutting the capacitor dielectric constitute a second electrode.
|
