METHOD FOR FORMING BURIED PLATE OF TRENCH CAPACITOR

摘要

A method for forming a buried plate in a trench capacitor is disclosed. The trench is completely filled with a dopant source material such as ASG. The dopant source material is then recessed and the collar material is deposited to form the collar in the upper portion of the trench. After drive-in of the dopants to form the buried plate, the dopant source material is removed and the collar materials may be removed.