STRUCTURE OF FLASH MEMORY DEVICE SUITABLE FOR MULTI-LEVEL PROGRAM METHOD USING TWO PROGRAM GATES AND FABRICATING METHOD THEREOF

摘要

PURPOSE: A structure of a flash memory device and a fabricating method thereof are provided to improve speed of a tunneling program method and perform a multi-level program by using two program gates in a program. CONSTITUTION: A plurality of highly-doped buried regions(31) are formed in a predetermined interval on a semiconductor substrate. A plurality of isolation oxide layers(32) are formed vertically to the highly-doped buried regions. Two program gates(33a) are formed on one isolation oxide layer. The program gates overlap partially with the highly-doped buried regions overlaps. A plurality of floating gates(35a) are arranged on the isolation oxide layer between the highly-doped buried regions. A plurality of control gates(39a) are formed between the highly-doped buried regions including the floating gates. A plurality of erasion gates are formed between the control gates.