Texas Instruments Incorporated
Semiconductor device with an integrated deep trench capacitor having high capacitance density and low equivalent series resistance

Abstract:

A semiconductor device includes an integrated trench capacitor in a substrate, with a field oxide layer on the substrate. The trench capacitor includes trenches extending into semiconductor material of the substrate, and a capacitor dielectric in the trenches on the semiconductor material. The trench capacitor further includes an electrically conductive trench-fill material on the capacitor dielectric. A portion of the capacitor dielectric extends into the field oxide layer, between a first segment of the field oxide layer over the trench-fill material and a second segment of the field oxide layer over the semiconductor material. The integrated trench capacitor has a trench contact to the trench-fill material in each of the trenches, and substrate contacts to the semiconductor material around the trenches, with no substrate contacts between the trenches.