US Patent 7932168 Method for fabricating bitline in semiconductor device

A method of a fabricating a bitline in a semiconductor device, comprising: forming an interlayer insulation layer that defines a bitline contact hole on a semiconductor substrate; forming a contact layer to fill the bitline contact hole; forming a bitline contact by planarizing the contact layer; forming a bitline stack aligned with the bitline contact; forming a high aspect ratio process (HARP) layer that extends along the bitline stack and the interlayer insulation layer while covering a seam exposed in a side portion of the bitline stack by excessive planarization during formation of the bitline contact; and forming an interlayer gap-filling insulation layer on the HARP layer that gap-fills the entire bitline stack.