Self-Aligned Gate Structure, Memory Cell Array, and Methods of Making the Same

摘要

A self-aligned gate structure includes a first gate region and a second gate region. The first gate region extends in semiconductor substrate portions to a lesser depth than in isolation trenches that are adjacent to the semiconductor substrate portions. The first gate region comprises a first conductive material. The second gate region is adjacent to the first gate region and extends above a surface of the semiconductor substrate. The second gate region includes a second conductive material.