METHOD FOR MANUFACTURING STACKED FLASH MEMORY CELL

摘要

PURPOSE: A method for manufacturing a stacked flash memory cell is provided to prevent a shift of threshold voltage of memory cells by enhancing a charge retention capability of a floating gate. CONSTITUTION: A gate oxide layer is formed on an active region of a semiconductor substrate(200). A structure sequentially stacked a floating gate, a dielectric film of ONO structure and a control gate are sequentially formed on a desired portion of the gate oxide(210-230). An oxide layer made of SiON is formed on the gate oxide layer including the stacked structure by an oxidation processing using N2O gas or NO gas as a source gas(240). An LDD(Lightly Doped Drain) region is formed in the substrate(250). After forming an insulating spacer at both sidewalls of the stacked structure(260), source and drain regions are formed(270).