DYNAMIC MEMORY DEVICE HAVING A SINGLE-CRYSTAL TRANSISTOR ON A TRENCH CAPACITOR STRUCTURE AND A FABRICATION METHOD THEREFOR

摘要

A DRAM device is mfd. by; forming a trench in a mono-Si substrate through a mask; filling it with doped polySi: forming an overlying oxide layer; removing the mask; growing a doped epitaxial mono-Si layer; forming a mask and etching away the mono-Si and oxide over the trench; refilling the window with polySi; removing the mask; and forming an access transistor over the trench by standard gate oxide growth and definition and source/drain implantation.