Deep trench isolation with tank contact grounding

摘要

An integrated circuit is formed on a substrate containing a semiconductor material having a first conductivity type. A deep well having a second, opposite, conductivity type is formed in the semiconductor material of the first conductivity type. A deep isolation trench is formed in the substrate through the deep well so as separate an unused portion of the deep well from a functional portion of the deep well. The functional portion of the deep well contains an active circuit element of the integrated circuit. The separated portion of the deep well does not contain an active circuit element. A contact region having the second conductivity type and a higher average doping density than the deep well is formed in the separated portion of the deep well. The contact region is connected to a voltage terminal of the integrated circuit.

主权项

1. A method of forming an integrated circuit, comprising:
providing a substrate comprising a semiconductor material of a first conductivity type; forming a deep well of a second, opposite, conductivity type disposed in said semiconductor material of said substrate, said deep well extending to a depth of 1 micron to 5 microns; subsequently forming a deep isolation trench disposed in said substrate through said deep well, so as to separate a functional portion of said deep well from a separated portion of said deep well, said separated portion being free of an active component of said integrated circuit, said separated portion being electrically isolated from said functional portion; forming an active component of said integrated circuit in said functional portion; forming a well contact region of said second conductivity type in said separated portion; and forming an electrical connection from said well contact region to a voltage terminal of said integrated circuit.