Selective etch for uniform metal trace exposure and milling using focused ion beam system

Abstract

A system and method for exposing and/or milling a copper metallization layer disposed in dielectric that may have an overlying polyimide layer preferably by use of a FIB machine system used for exposing/milling aluminum metallization layers is disclosed. The method includes using a gas assisted (GAS) system for exposing a portion of a copper metal trace disposed in a dielectric and includes the step of removing a portion of the dielectric overlying the portion of the metal trace using the GAS system activated with a dielectric selective chemical that does not have a significant spontaneous (non ion-beam induced) reaction with the metal trace. The system includes a focused ion beam (FIB) machine for exposing/milling a portion of a metal trace disposed in a dielectric substrate wherein the metal trace is copper.

Dependencies are inferred from the claim text.