Semiconductor device and method for manufacturing the same

A semiconductor device, comprising:

• a substrate;
• a first conductive type first well region;
• a second conductive type epitaxial layer disposed over the substrate, the first conductive type first well region being disposed in the substrate and the second conductive type epitaxial layer;
• a second conductive type first buried layer and a second conductive type second buried layer disposed in the substrate and the second conductive type epitaxial layer, wherein the second conductive type first buried layer and the second conductive type second buried layer are disposed at opposite sides of the first conductive type first well region, respectively, wherein the first conductive type is different from the second conductive type;
• a first conductive type second well region disposed in the second conductive type epitaxial layer and being in direct contact with the first conductive type first well region;
• a second conductive type third buried layer disposed in the first conductive type first well region and/or the first conductive type second well region;
• a second conductive type doped region disposed in the first conductive type second well region;
• a gate structure disposed over a top surface of the second conductive type epitaxial layer;
• a drain contact plug electrically connected to either the first conductive type second well region or the second conductive type doped region;
• and
• a source contact plug electrically connected to the other of the first conductive type second well region or the second conductive type doped region.