METHOD FOR IMPROVING PROFILE OF SHALLOW-TRENCH-ISOLATION TRENCH

摘要

PURPOSE: A method for improving a profile of a shallow-trench-isolation(STI) trench is provided to prevent a junction leakage, by discontinuously applying a radio frequency(RF) power to round upper and lower portions of the trench. CONSTITUTION: A plasma etching equipment has a process chamber, a reaction gas supplying unit, a plasma power supplying unit and a radio frequency(RF) power source. A trench is formed on a wafer by using a predetermined layer having a pattern, wherein an on/off switching operation having a duty ratio is performed regarding the RF power source to round upper and lower portions of the trench. The on/off duty ratio of the RF power is established from 20 to 40 percent.