High voltage semiconductor device and method for fabricating the same

A high voltage semiconductor device, comprising:

• an epitaxial layer with a first conductivity type formed on a semiconductor substrate, having a first high voltage well with a second conductivity type opposite to the first conductivity type therein;
• a gate structure disposed on the epitaxial layer of the first high voltage well;
• a body doped region with the first conductivity type in the first high voltage well on a first side of the gate structure;
• a source doped region in the body doped region;
• a drain doped region in the first high voltage well on a second side opposite to the first side of the gate structure;
• and
• a first lightly doped region with the first conductivity type in the body doped region and near to the source doped region.

A method for fabricating a high voltage semiconductor device, comprising:

• forming an epitaxial layer with a first conductivity type on a semiconductor substrate;
• forming a first high voltage well with a second conductivity type opposite to the first conductivity type in the epitaxial layer;
• forming a body doped region with the first conductivity type in the first high voltage well;
• forming a drain doped region in the first high voltage well;
• forming a source doped region in the body doped region;
• forming a gate structure on the epitaxial layer of the first high voltage well, such that the body doped region and the drain doped region are in the first high voltage well on both sides of the gate structure;
• and
• forming a first lightly doped region with the first conductivity type in the body doped region and near to the source doped region.