A method of forming a device is disclosed. A substrate having a device region is provided. The device region comprises a source region, a gate and a drain region defined thereon. A drift well is formed in the substrate adjacent to a second side of the gate. The drift well underlaps a portion of the gate with a first edge of the drift well beneath the gate. A secondary portion is formed in the drift well. The secondary portion underlaps a portion of the gate with a first edge of the secondary portion beneath the gate. The first edge of the secondary portion is offset from the first edge of the drift well. A gate dielectric of the gate comprises a first portion having a first thickness and a second portion having a second thickness. The second portion is over the secondary portion.