METHOD FOR FORMING SHALLOW TRENCH ISOLATION OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a shallow trench isolation of a semiconductor device is provided to be capable of reducing leakage current by controlling the lower portion of the shallow trench isolation for blocking or lengthening a leakage current path. CONSTITUTION: After depositing a pad dielectric(4) on a silicon substrate(2), a photoresist pattern is formed on the resultant structure. An RIE(Reactive Ion Etching) process is carried out at the resultant structure by using the photoresist pattern as an etching mask for selectively exposing the silicon substrate. A plurality of anisotropic grooves is formed in the silicon substrate by selectively etching the silicon substrate using an anisotropic etching solution. A plurality of shallow trench isolations(10) is formed by etching the anisotropic grooves using reactive ions. Preferably, the pad dielectric is made of an oxide layer(4a) and a nitride layer(4b).