Patent ID: 6127258
Filing Date: 2000-10-03
Classification: H01L

Abstract:
A method for forming a semiconductor device, comprising:forming via-level dielectric film overlying a semiconductor device substrate;forming a trench-level dielectric film directly on and in contact with the via-level dielectric film;etching a via opening in the trench-level dielectric film with a first etch chemistry, wherein the first etch chemistry has a higher etch selectivity to the trench-level dielectric film than to the via-level dielectric film;providing a photoresist layer overlying the trench-level dielectric film, the photoresist layer having a photoresist opening overlying the via opening in the trench-level dielectric film;etching the via-level dielectric film with a second etch chemistry to extend the via opening into the via-level dielectric film; andetching into the trench-level dielectric film through the photoresist opening to form a trench opening.