High-voltage semiconductor device and method of manufacturing thereof

A method of manufacturing a high-voltage semiconductor device, the method comprising:

• forming a well in a semiconductor substrate;
• forming a device isolation film in a portion of the semiconductor substrate;
• forming a series of drift regions below the surface of the semiconductor substrate;
• forming a gate electrode on the surface of the semiconductor substrate so as to overlap a portion of at least one drift region;
• and
• forming a source region and a drain region below the surface of the semiconductor substrate within drift regions on opposing sides of the gate electrode.

A method of manufacturing a transistor for a high-voltage semiconductor device, the method comprising:

• forming a well in a semiconductor substrate;
• forming a device isolation film in a portion of the semiconductor substrate;
• forming a series of drift regions below the surface of the semiconductor substrate by forming a mask pattern for implanting ions into the well, implanting an N-type dopant into the surface exposed by the formed mask pattern in order to form a doped layer, and diffusing the doped layer to a portion of the surface below where the gate electrode will be formed;
• forming a gate electrode on the surface of the semiconductor substrate so as to overlap a portion of two drift regions on opposing sides of the gate electrode;
• and
• forming a source region below the surface of the semiconductor substrate in one drift region on one side of the gate electrode and a drain region below the surface of the semiconductor substrate in the drift region on the opposing side of the gate electrode.