High-voltage semiconductor devices and methods of formation

A semiconductor device, comprising:

• a first source/drain region comprising a first source/drain active region that extends above a substrate of the semiconductor device;
• a second source/drain region comprising a second source/drain active region that extends above the substrate
• wherein at least one of the first source/drain active region or the second source/drain active region comprises a planar active region;
• a channel active region between the first source/drain active region and the second source/drain active region and extending above the substrate,
• wherein the second source/drain active region and the channel active region are directly connected;
• and
• a gate structure over the channel active region and wrapping around the channel active region on at least three sides of the channel active region.

A method, comprising:

• etching a substrate and in a device region of a semiconductor device to form a first source/drain active region;
• etching the substrate in the device region to form a second source/drain active region;
• etching the substrate in the device region to form a channel active region,
• wherein the channel active region is between the first source/drain active region and the second source/drain active region, and
• wherein at least one of the first source/drain active region, the second source/drain active region, or the channel active region comprises a planar active region;
• and
• forming a gate structure over at least three sides of the channel active region.