MANUFACTURING METHOD OF DYNAMIC RANDOM ACCESS MEMORY IC

摘要

The method comprises; (A) filling a trench (12) with the 1st insulating material after forming the 1st trench by etching the fixed device separation region of the 1st conduction type semiconductor substrate (10); (B) forming a gate (18) with a gate insulating layer on the surface of a trench separation region; (C), etching an insulating layer located between the fixed gates until the surface of the substrate (10) exposed and forming bit line (24) connecting with the exposed surface; (D) forming the 2nd shallower trench (30) than the depth of the trench separation region by aligning with photolithography of capacitor region close to each of the 1st trenches (12), (E) forming a dielectric layer (36) to wrap round the 1st conduction layer (34), and (F) forming the 2nd conduction layer (38) on the whole surface of the above substrate (10).