In accordance with an embodiment, a semiconductor component includes a plurality of layers of compound semiconductor material over a body of semiconductor material and first and second filled trenches extending into the plurality of layers of compound semiconductor material. The first trench has first and second sidewalls and a floor and a first dielectric liner over the first and second sidewalls and the second trench has first and second sidewalls and a floor and second dielectric liner over the first and second sidewalls of the second trench.