Integrated Circuit Having Back Gating, Improved Isolation and Reduced Well Resistance and Method to Fabricate Same

摘要

A structure includes a silicon substrate; at least two wells in the silicon substrate; and a deep trench isolation (DTI) separating the two wells. The DTI has a top portion and a bottom portion having a width that is larger than a width of the top portion. The structure further includes at least two semiconductor devices disposed over one of the wells, where the at least two semiconductor devices are separated by a shallow trench isolation (STI). In the structure sidewalls of the top portion of the DTI and sidewalls of the STI are comprised of doped, re- crystallized silicon. The doped, re-crystallized silicon can be formed by an angled ion implant that uses, for example, one of Xe, In, BF2, B18H22, C16H10, Si, Ge or As as an implant species to amorphize the silicon, and by annealing the amorphized silicon to re-crystallize the amorphized silicon.

主权项

1. A structure, comprising:
a trench formed at least partially in a silicon substrate, the trench having a top portion and a bottom portion having a width that is larger than a width of the top portion; where sidewalls of the top portion of the trench are comprised of amorphous silicon, where the top portion of the trench is contained within a silicon-on-insulator layer disposed over a layer of dielectric material that in turn is disposed over the silicon substrate, and where the bottom portion of the trench is contained within the silicon substrate.