Lateral double diffused MOS transistor

A lateral double diffused MOS transistor includes a drain region positioned in a central region of an upper surface portion of an epitaxial layer, the drain region including a first well of a second conductive type, a source region positioned in the upper surface portion of the epitaxial layer and spaced apart from the drain region, the source region having a ring shape to surround the drain region and including a second well of the first conductive type, a first gate electrode disposed on the epitaxial layer and between the drain region and the source region, a P-sub region disposed on an upper surface of the epitaxial layer and laterally spaced apart from the source region, and a deep well of the second conductive type, disposed in the epitaxial layer, the deep well radially extending from the first well through the second well to entirely surround the drain region and the source region.