The disclosure provides a structure with a buried doped region, and methods to form the same. A structure may include a semiconductor substrate including a first well. A first terminal includes a first doped region in the first well. A second terminal includes a second doped region in the first well. The first well horizontally separates the first doped region from the second doped region. A first buried doped region is in the first well. The first buried doped region overlaps with, and is underneath, the first doped region. The first well vertically separates the first doped region from the first buried doped region.