MANUFACTURING METHOD FOR BURIED HIGH DENSITY ION INJECTION AREA

摘要

The present invention is to provide a method for forming buried highly-concentration ion implantation region which is used for source/drain line of memory cell. The method for forming the buried highly-concentration ion implantation region according to the present invention comprises: a) forming a spacer(7) on the side walls of an isolation area of wafer; b) performing a first channel field ion implantation after a channel ion implantation making process; c) implanting high-concentration ions after removing the channel ion implantation mask and masking process for buried high-concentration ion implantation region; and d) forming a field oxide layer(10) after removing the mask for the high-concentration ion implantation region. Thereby, the present invention provides an improved punchthrough property by pocketing the buried high-concentration ion implantation region through the additional channel ion implantation.