An integrated semiconductor structure that has first and second bipolar transistor structures. The first bipolar transistor structure has a doped tank region in contact with a doped tank region located underneath a contacting sinker. The second bipolar transistor structure has a doped buried region that is the same dopant type as its doped tank region. A method for fabricating an integrated semiconductor structure in a bulk semiconductor wafer. A first patterned photomask is used to form a doped buried region and a doped tank region within the first bipolar transistor structure. A second patterned photomask is used to form a doped buried region and a doped tank region within the second bipolar transistor, plus a doped buried region and a doped tank region underneath a contacting sinker adjacent to the first bipolar transistor.