Patent ID: 9463485
Filing Date: 2016-10-11
CPC Classification: B05B,B23K,B41J

Claim Text:
1. A method of forming a substrate for a fluid ejection device, the substrate having a first side and a second side opposite the first side, the method comprising: forming an opening through the substrate, the opening having a long axis profile and a short axis profile, the long axis profile including a first portion extending from a minimum dimension of the long axis profile to the first side of the substrate, and a second portion including and extending from the minimum dimension of the long axis profile to the second side of the substrate; 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; and forming the protective layer on sidewalls of the short axis profile of the opening extending from the second side of the substrate to the first side of the substrate.