A double diffused region (65), (75), (85) is formed in a semiconductor substrate or in an epitaxial layer (20) formed on the semiconductor substrate. The double diffused region is formed by first implanting light implant specie such as boron through an opening in a photoresist layer prior to a hard bake process. Subsequent to the hard bake process, a heavy implant species such as arsenic is implanted into the epitaxial layer. During subsequent processing, such as during LOCOS formation, a double diffused region is formed by a thermal anneal. A dielectric layer (120) is formed on the epitaxial layer (20) and gate structures (130), (135) are formed over the dielectric layer (120).