Method of forming buried-strap with reduced outdiffusion including removing a sacrificial insulator leaving a gap and supporting spacer

摘要

A method and structure for forming an integrated circuit memory device includes forming a trench conductor in a trench, forming an isolation collar along a perimeter of an upper portion of the trench conductor, forming supporting spacers above the isolation collar, forming a sacrificial layer between the supporting spacers along an upper surface of the trench conductor, forming an insulator above the sacrificial layer, forming a gate conductor above the insulator, removing the sacrificial layer to form a gap between the insulator and the trench conductor, wherein the supporting spacers maintain a relative position of the gate conductor, the insulator and the trench conductor and forming a conductive strap in the gap.