Semiconductor structure with junction leakage reduction

A semiconductor structure is provided, which includes a semiconductor substrate, a first well region, a second well region, an active region, a shallow trench isolation (STI) and at least one deep trench isolation (DTI). The first well region of a first conductive type is on the semiconductor substrate. The second well region of a second conductive type is on the semiconductor substrate and adjacent to the first well region. The second conductive type is different from the first conductive type. The active region is on the first well region. The active region has a conductive type the same as the second conductive type of the second well region. The STI is between the first and second well regions. The DTI is below the STI. The DTI is disposed between at least a portion of the first well region and at least a portion of the second well region.