Patent ID: 6734078
Filing Date: 2004-05-11
Classification: H01L

Abstract:
A method for manufacturing semiconductors with trench capacitors having a low-resistance buried strap, comprising the following steps:providing a substrate; forming a trench in the substrate; forming a glass doping layer with a first predetermined depth at the bottom of the trench; forming a first dielectric layer covering the glass doping layer in the trench; diffusing dopants of the glass doping layer to the substrate by annealing to form a buried plate; removing the first dielectric layer and the glass doping layer; sequentially forming a second dielectric layer and a first conductive layer having depths approximately equal to the first predetermined depth in the trench, wherein the region above the first conductive region is defined as the collar region; forming a U-shaped insulating layer in the collar region; forming a collar conductive layer at the bottom of the U-shaped insulation layer in the collar region; removing the U-shaped insulating layer not in contact with the collar conductive layer to form a collar insulating layer; and forming the buried strap in the trench.