Semiconductor transistor device and method of manufacturing the same

A method for manufacturing a semiconductor transistor device, the method comprising:

• etching a vertical gate trench into a silicon region;
• depositing a silicon gate material on a first interlayer dielectric formed in the vertical gate trench so that an upper side of the first interlayer dielectric is covered;
• depositing a second interlayer dielectric on an upper side of the silicon gate material in the vertical trench;
• etching through a portion of the second interlayer dielectric in the vertical trench to partly uncover the upper side of the silicon gate material;
• etching through the partly uncovered upper side of the silicon gate material in the vertical gate trench to partly uncover the upper side of the interlayer dielectric so that a silicon gate region of a gate electrode of the semiconductor transistor device remains in the vertical gate trench;
• and
• depositing a metal material into the vertical gate trench so that the partly uncovered upper side of the interlayer dielectric is covered by the metal material.