METHOD FOR OXIDIZING POLYCIDE OF FLASH ELECTRICALLY ERASABLE AND PROGRAMMABLE READ-ONLY-MEMORY

摘要

PURPOSE: A method for oxidizing polycide of a flash electrically-erasable-and-programmable read-only-memory(EEPROM) is provided to form a normal tungsten silicide layer by oxidizing polycide of a memory cell, and to guarantee a coupling ratio by preventing an ONO smiling phenomenon occurring at both sides of a dielectric layer and a phenomenon that the thickness at both sides of a tunnel oxide layer is increased. CONSTITUTION: A wafer on which polycide used for as an electrode of a semiconductor device is evaporated, is prepared. The wafer is loaded into a chamber which is set at the first temperature. The temperature of the chamber is ramped up to the second temperature to anneal the wafer. The temperature of the chamber is ramped down to the first temperature. The wafer is unloaded after a dry oxidation process.