Deep trench capacitor

摘要

A deep trench capacitor structure including an SOI substrate comprising an SOI layer, a rare earth oxide layer, and a bulk substrate, the rare earth oxide layer is located below the SOI layer and above the bulk substrate, and the rare earth oxide layer insulates the SOI layer from the bulk substrate, and a deep trench capacitor extending from a top surface of the SOI layer, through the rare earth oxide layer, down to a location within the bulk substrate, the rare earth oxide layer contacts the deep trench capacitor at an interface between the rare earth oxide layer and the bulk substrate forming an incline away from the deep trench capacitor.

主权项

1. A deep trench capacitor structure in a semiconductor-on-insulator (SOI) substrate, the structure comprising:
a SOI substrate comprising a SOI layer, a rare earth oxide layer, and a bulk substrate; the rare earth oxide layer being a first epitaxial layer and being located below the SOI layer and above the bulk substrate, and the rare earth oxide layer insulating the SOI layer from the bulk substrate, the SOI layer being a second epitaxial layer; and a deep trench capacitor extending from a top surface of the SOI layer, through the rare earth oxide layer, down to a location within the bulk substrate, wherein the rare earth oxide layer contacts the deep trench capacitor at an interface between the rare earth oxide layer and the bulk substrate and from the interface the rare earth oxide layer is inclined away from the deep trench capacitor, at an angle relative to an interface of the deep trench capacitor and the bulk substrate, and wherein the SOI layer is also inclined away from the deep trench capacitor.