IMPROVED STACKED TRENCH TYPE DRAM CELL FOR RESOLVING PROBLEM OF PHOSPHOROUS DIFFUSION INTO ACCESS TRANSISTOR CHANNEL REGIONS

摘要

PURPOSE: To provide a stacked trench type DRAM cell which has been improved to solve the problem of phosphorous diffusion in access transistor channel regions. ;CONSTITUTION: The sidewalls of trenches are lined with a dielectric lining 91, trenches 41A are doped with a low-diffused n-type impurity, which is the same as those of this sidewall and they are electrically contacted to access transistor source-drain regions 16 through the bottoms of the trenches 41A, to thereby solve the problem that phosphorous diffused from storage node capacitor plates of stacked trench type DRAM cells to access transistor channel regions of the cells. Thus phosphorus in storage node capacitor plates 12 is made distant from the access transistor channels, and its diffusion has no effect on the performance characteristics of the access transistors.;COPYRIGHT: (C)1994,JPO