The present disclosure provides a semiconductor device having a transistor. The transistor includes a substrate and first and second wells that are disposed within the substrate. The first and second wells are doped with different types of dopants. The transistor includes a first gate that is disposed at least partially over the first well. The transistor further includes a second gate that is disposed over the second well. The transistor also includes source and drain regions. The source and drain regions are disposed in the first and second wells, respectively. The source and drain regions are doped with dopants of a same type.