Patent ID: 6809001
Filing Date: 2004-10-26
Classification: H01L

Abstract:
A method for producing a semiconductor device having a cylindrical storage node comprising a bottom portion and a cylindrical portion which surrounds an outer circumference of said bottom portion and extends upward, which comprises the steps of:forming a contact hole which penetrates an interlayer insulating film formed on a semiconductor substrate; forming an electric conductive film on said interlayer insulating film whereby said contact hole is filled to obtain a contact to said substrate; forming an insulating film on said electric conductive film; patterning by an anisotropic etching said insulating film and said electric conductive film to form a configuration corresponding to said cylindrical portion so that a core and the bottom portion of said cylindrical portion are formed; forming the cylindrical portion on the side of said core and said bottom portion wherein an outer wall of said cylindrical portion is roughened, comprising the sequential steps of forming a film made of amorphous silicon on said core and said bottom portion; roughening an outer surface of said film by forming silicon grains in the outer surface of it; and conducting an anisotropic etching for patterning to form said cylindrical portion having a side-wall like shape at the side of said core and said bottom portion; removing said core; forming a dielectric film to cover said cylindrical storage node comprising said cylindrical portion and said bottom portion; and forming a cell plate on said dielectric film, whereby a capacitor constituted by said cylindrical storage node, said dielectric film and said cell plate is formed, wherein said method for producing a semiconductor device is performed such that the inner wall of the cylindrical portion having the roughened outer wall remains in a form of said amorphous silicon.