Patent ID: 6482744
Filing Date: 2002-11-19
Classification: H01J

Abstract:
A method of etching a contact hole to a bitline, said contact hole being defined by a photoresist pattern formed atop of an anti-reflective coating, a bulk oxide layer, and a liner oxide layer, said etching performed in a plasma etching chamber having an upper electrode and a susceptor, said method comprising:etching away said anti-reflective coating; performing a first etch of said bulk oxide layer, said first etch performed with said upper electrode and said susceptor set to a first distance; performing a second etch of said bulk oxide layer, said second etch performed with said upper electrode and said susceptor set to a second distance; performing a third etch of said bulk oxide layer, said third etch performed with said upper electrode and said susceptor set to a third distance; and etching away said an exposed portion of said liner oxide.