MANUFACTURE OF DRAM CELL IN WHICH HEMISPHERICAL GRAIN TYPE POLYSILICON AND SELECTIVE POLYSILICON ETCHBACK ARE USED

摘要

PROBLEM TO BE SOLVED: To increase the charge storing capacity of the memory cell, etc., of a DRAM. SOLUTION: A storage node 64 for capacitor having an increased charge storing capacity and its manufacturing method. A thin film layer 70 of hemispherical polysilicon is deposited on a doped polysilicon region 68. The doped polysilicon region 68 and hemispherical polysilicon thin film layer 70 are etched by using an etching compound which etches the area 68 faster than the layer 70 so as to increase the area of the upper surface 66 of the node.