A semiconductor device includes a drift region, an active region in the drift region, and an edge termination region in the drift region adjacent to the active region. The edge termination region includes one or more guard rings in the drift region. The drift region has a first conductivity type and the one or more guard rings have a second conductivity type. The edge termination region may also include a passivation layer that is disposed on the one or more guard rings and on the drift region in the edge termination region. The passivation layer has a first thickness over each guard ring and a second thickness over the drift region, where the first thickness is greater than the second thickness. Alternatively, the edge termination region may also include a passivation layer that is only disposed on the one or more guard rings in the edge termination region.