Methods of performance improvement of HVMOS devices

Methods fabricate DEMOS devices having varied channel lengths and substantially similar threshold voltages. A threshold voltage is selected for first and second devices. First and second well regions are formed. First and second drain extension regions are formed within the well regions. First and second back gate regions are formed within the well regions according to the selected threshold voltage. First and second gate structures are formed over the first and second well regions having varied channel lengths. A first source region is formed in the first back gate region and a first drain region is formed in the first drain extension region. A second source region is formed in the second back gate region and a second drain region is formed in the drain extension region.