A device includes a substrate, a first well doped with dopants of a first conductivity type defined in the substrate, and a second well doped with dopants of a second conductivity type different than the first conductivity type defined in the substrate adjacent the first well to define a PN junction. The second well includes a silicon alloy portion displaced from the PN junction. A collector region contacts one of the first or second wells and has a dopant concentration higher than its contacted well. An emitter region contacts the other of the first or second wells and is doped with dopants of the first or second conductivity type different than the first or second well contacted by the emitter region. A base region contacts the other of the first or second well and has a dopant concentration higher than the first or second well contacted by the base region.