Semiconductor Device and Method for Fabricating the Same

A semiconductor device, comprising:

• a shallow trench isolation (STI) layer in a semiconductor substrate;
• a field oxide layer in a portion of the semiconductor substrate adjacent to the STI layer;
• a first gate oxide layer on or over the semiconductor substrate and adjacent to the field oxide layer;
• a second gate oxide layer on or over the semiconductor substrate at sides of the first gate oxide layer;
• and
• a gate pattern on or over the field oxide layer, the first gate oxide layer, and the second gate oxide layer.

A method for fabricating a semiconductor device, comprising:

• forming a shallow trench isolation (STI) layer in a substrate;
• forming a field oxide layer adjacent to the STI layer in the semiconductor substrate;
• forming a first gate oxide layer adjacent to the field oxide layer;
• forming a second gate oxide layer adjacent to the first gate oxide layer, the second gate oxide layer having a thickness less than a thickness of the first gate oxide layer;
• and
• forming a gate pattern over the field oxide layer, the first gate oxide layer, the second gate oxide layer, and part of the STI layer.