Flash memory device fabrication by forming gate electrode of string selection transistor on substrate between two trench isolation regions, forming trenches, forming inter-gate dielectric layer segments, and forming string selection line

摘要

Flash memory device fabrication includes forming two trench isolation regions at side-by-side locations in a semiconductor substrate (100); forming gate electrode of string selection transistor on substrate portion extending between the trench isolation regions; forming respective trenches in the trench isolation regions; forming inter-gate dielectric layer (150) segments that line bottoms and sidewalls of respective trenches; and forming string selection line that extends on inter-gate dielectric layer segments and electrically contacts upper surface and sidewalls of gate electrode. An independent claim is included for formation of string selection transistor of a NAND-type EEPROM device.