Methods for fabricating active devices on a semiconductor-on-insulator substrate utilizing multiple depth shallow trench isolations

摘要

Methods for fabricating a device structure in a semiconductor-on-insulator substrate. The method includes forming a first isolation region in the substrate device layer that extends from a top surface of the device layer to a first depth and forming a second isolation region in the semiconductor layer that extends from the top surface of the semiconductor layer to a second depth greater than the first depth. The method further includes forming a doped region of the device structure in the semiconductor layer that is located vertically between the first isolation region and the insulating layer.