| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of forming a MOS semiconductor device that improves the integration degree of an IC (integrated circuit) and prevents short-channel effect. SOLUTION: A method of forming memory devices, such as DRAM access transistors, having recessed gate structures is disclosed. Field oxide areas (21) for isolation are first formed over a semiconductor substrate subsequent to which transistor trenches (22) are patterned and etched in a silicon nitride layer (18). The field oxide areas adjacent to the transistor trenches are then recessed so that subsequently deposited polysilicon for gate structure formation can be polished relative to the adjacent and elevated silicon nitride. COPYRIGHT: (C)2010,JPO&INPIT |
