FLUID EJECTION DEVICE

摘要

A method of forming a substrate for a fluid ejection device includes forming an opening through the substrate, with the opening having a long axis profile and a short axis profile, and with the long axis profile including a first portion extending from a minimum dimension of the long axis profile to a first side of the substrate, and a second portion including and extending from the minimum dimension of the long axis profile to a second side of the substrate opposite the first side. The method also includes forming a protective layer on sidewalls of the second portion of the long axis profile of the opening and excluding the protective layer from sidewalls of the first portion of the long axis profile of the opening.