Abstract: A semiconductor device and a fabrication method are provided. The semiconductor device is fabricated by providing a substrate with a device area surrounded by a seal ring area, forming a buried deep-well layer in the substrate of the seal ring area, forming a first well region and a second well region in the substrate above the buried deep-well layer with the first well region surrounding the device area and the second well region surrounding the first well region, forming a heavily doped region in the substrate above the buried deep-well layer and between the first well region and the second well region, and forming a seal ring structure connecting to the heavily doped region. The buried deep-well layer, the first well region, and the second well region all have a first doping type while the heavily doped region and the substrate have a second doping type.

Abstract: A semiconductor device and a fabrication method are provided. The semiconductor device is fabricated by providing a substrate with a device area surrounded by a seal ring area, forming a buried deep-well layer in the substrate of the seal ring area, forming a first well region and a second well region in the substrate above the buried deep-well layer with the first well region surrounding the device area and the second well region surrounding the first well region, forming a heavily doped region in the substrate above the buried deep-well layer and between the first well region and the second well region, and forming a seal ring structure connecting to the heavily doped region. The buried deep-well layer, the first well region, and the second well region all have a first doping type while the heavily doped region and the substrate have a second doping type.