Semiconductor device and method of fabricating the same

A method of fabricating a semiconductor device, comprising:

• forming a top doped region of a second conductivity type;
• forming a compensation doped region of a first conductivity type, and the compensation doped region being located in the top doped region,
• forming a drain region on a first side of the top doped region, and the drain region being of the first conductivity type;
• and
• forming a source region on a second side of the top doped region, the source region being of the first conductivity type, wherein a channel region in a portion of a substrate between the source region and the drain region,
• wherein a doping concentration of the top doped region is gradually decreased from a region near the channel region to a region near the drain region.

A metal oxide semiconductor transistor, comprising:

• a drain region of a first conductivity type located in a substrate;
• a source region of the first conductivity type, located in the substrate;
• a gate located above the substrate between the source region and the drain region;
• a gate dielectric layer located between the gate and the substrate;
• and
• a compensation doped region of the first conductivity type, located in the substrate between the source region and the drain region;
• and
• a top doped region of a second conductivity type, located below the compensation doped region, and having a doping concentration gradually decreased from a region near the source region to a region near the drain region.

A method of fabricating a semiconductor device, comprising:

• forming an N-type doped layer in a substrate;
• forming a top doped region of a P-type in the N-type doped layer between a region predetermined for forming a drain region and a region predetermined for forming a channel region;
• implanting an N-type dopant in the top doped region to form a compensation doped region in the top doped region;
• forming the drain region of an N-type in the N-type doped layer;
• and
• forming a source region of the N-type conductivity type on a side of the channel region.