APPARATUS AND METHODS FOR ENHANCING BANDWIDTH IN TRENCH ISOLATED INTEGRATED CIRCUITS

摘要

Provided herein are apparatus and methods for enhancing bandwidth in trench isolated integrated circuits. In certain configurations, an auxiliary trench forming floating regions between moat isolation regions can isolate parasitic sidewall capacitances of active device regions from ground or AC ground. In this manner the active device regions are merged by the auxiliary trench so as to improve circuit bandwidth and enhance circuit performance. When arranged or combined within a circuit branch, transistors within each floating moat can operate with relatively small parasitic displacement current and can have improved performance.

主权项

1. An attenuator device comprising:
a substrate that is coupled to a reference voltage; a first active device formed in a first active device region of the substrate wherein the first active device region is surrounded by a first trench isolation structure; a second active device formed in a second active device region wherein the second active device is surrounded by a second trench isolation structure; wherein a third trench isolation region is interposed between the first and second active device regions to define a first and a second floating region of the substrate such that there is a first capacitance between the first active device region and the first floating region and a second capacitance between the first floating region and the second floating region and a third capacitance between the second floating region and the second active device region; wherein the first active device has a first operating voltage and the second active device has a second operating voltage and wherein the difference between the first and second operating voltages is less than the difference between the first operating voltage and the reference voltage.