Strained vertical channel semiconductor device, method of manufacturing the same, and electronic apparatus including the same

A semiconductor device, comprising:

• a vertical channel portion on a substrate;
• source and drain portions located at an upper end of the channel portion and a lower end of the channel portion relative to the substrate;
• and
• a first gate stack on a first side of the channel portion in a lateral direction, and a second gate stack on a second side of the channel portion in the lateral direction, wherein the second side is opposite to the first side,
• wherein a first gate dielectric layer in the first gate stack partially overlaps with a second gate dielectric layer in the second gate stack so as to form a stack of the first gate dielectric layer and the second gate dielectric layer, and a thickness of at least part of the stack is a sum of a thickness of the first gate dielectric layer and a thickness of the second gate dielectric layer.