Patent ID: 7372102

Claim:
A trench structure in a semiconductor substrate, comprising: a silicon oxide filled shallow trench located in a first portion of the semiconductor substrate and having a depth ranging between about 1100 Angstroms and about 2000 Angstroms; a deep trench located in the insulator filled shallow trench and extending into an underlying second portion of the semiconductor substrate, wherein the deep trench has a depth ranging between about 4 um and about 10 um and a diameter ranging between about 0.5 um and about 1.6 um; a channel stop region located in a third portion of the semiconductor substrate that is directly underlying the deep trench; insulator sidewalls located on sides of a bottom portion of the deep trench; a polysilicon region located in the bottom portion of the deep trench and interfacing the insulator sidewalls; and a insulator located in a top portion of the deep trench and overlying the polysilicon region, wherein sides of the insulator interface the insulator filled shallow trench, and wherein the insulator comprises silicon oxide.