Deep trench-buried layer array and integrated device structures for noise isolation and latch up immunity

摘要

The preferred embodiment of the present invention provides a buried layer that improves the latch up immunity of digital devices while providing isolation structures that provide noise isolation for both the digital and analog devices. The buried layer of the preferred embodiment is formed to reside within or below the subcollector region in the transistor. Additionally, in the preferred embodiment the subcollector is isolated from buried layer outside the transistor region by deep isolation trenches formed at the edges of the subcollector. Additionally, an array of deep isolation trenches provides increased isolation between devices where needed. Thus, the preferred embodiment of the present invention provides an integrated circuit structure and method that provides improved latchup immunity while also providing improved noise tolerance.