METHOD FOR FABRICATING FLASH MEMORY CELL DEVICE IN SEMICONDUCTOR

摘要

PURPOSE: A method for fabricating a flash memory cell device in semiconductor is provided to improve program efficiency of a flash cell by increasing contact area between a floating gate and a control gate. CONSTITUTION: A flash tunnel oxide layer(30) for isolation is formed on a silicon substrate(10). Polysilicon to be used as a floating gate(40) is deposited on the flash tunnel oxide layer. A buffer oxide layer is deposited on the floating gate and is pattern-etched to strip photoresist. After the polysilicon on a planar nitride layer is eliminated, an uneven floating gate is formed. An ONO layer(70) is deposited on the floating gate, and polysilicon to be used as a control gate(80) is deposited. A source/drain implant process is performed to form a source/drain(20). The control gate is patterned and etched to form a stacked flash cell.