A semiconductor device includes a first dielectric layer on a substrate, the first dielectric layer including a first dielectric portion over a first doped well region of a first conductivity type and a second dielectric portion over a second doped well region of a second conductivity type, and a second dielectric layer on the substrate directly adjacent the first dielectric layer. The second dielectric layer is over the second doped well region. A first conductive gate structure is over the first and second dielectric layers. A third dielectric layer is on the substrate over the second doped well region and separated a first distance from the second dielectric layer. A second conductive gate structure is over the third dielectric layer. A third doped region of the second conductivity type is implanted in the second doped well region a second distance from the third dielectric layer and the second conductive gate structure.