Terminations for semiconductor devices with floating vertical series capacitive structures

摘要

This invention relates to achieving high breakdown voltage and low on-resistance in semiconductor devices that have top, intermediate and bottom regions with a controllable current path traversing any of these regions. The device has an insulating trench that is coextensive with the top and intermediate regions and girds these regions from at least one side and preferably from both or all sides. A series capacitive structure with a biased top element and a number of floating elements is disposed in the insulating trench, and the intermediate region is endowed with a capacitive property that is chosen to establish a capacitive interaction or coupling between the series capacitive structure and the intermediate region so that the breakdown voltage V_BD is maximized and on-resistance is minimized. A second series capacitive structure disposed in a second insulating trench can be employed to terminate the device.