METHOD FOR MANUFACTURING FLASH MEMORY CELL

摘要

PURPOSE: A method for manufacturing flash memory cell is provided to assure the margin for patterning processes of first and second polysilicon film. CONSTITUTION: A method for manufacturing flash memory cell comprises: a step of forming an isolation film and a first polysilicon film; a step of forming a floating gate; a step of forming a dielectric film and a second polysilicon film; a step of forming a control gate; a step of forming a cell source/drain mask; and a step of forming source and drain areas. The floating gate is formed by patterning a portion of the first polysilicon film. The control gate is formed by patterning the second polysilicon film to be crossed with the isolation film. The mask is overlapped with the control gate. The source and drain areas are formed by an impurity ion implantation process after the isolation film is removed by a self align source etching process.