Semiconductor device including gate stack formed on inclined surface and method of fabricating the same

A method of fabricating a semiconductor device, the method comprising:

• forming a gate stack structure including a gate electrode on an entirety of an inclined surface of a substrate such that the gate electrode is formed only on the inclined surface;
• forming a first impurity region on a first upper surface of the substrate, the first upper surface having a different height than a second upper surface of the substrate and the first upper surface extending from a lower portion of the inclined surface;
• and
• forming a second impurity region on the second upper surface of the substrate, the second upper surface extending from an upper portion of the inclined surface and the first upper surface being connected to the second upper surface by the inclined surface;
• wherein
• a channel between the first impurity region and the second impurity region is formed along the inclined surface in a crystalline direction.