Patent ID: 8551692
Filing Date: 2013-10-08
Classification: B41J

Abstract:
1. A process for making a nozzle for ejecting fluid droplets, the process comprising: forming a patterned layer of photoresist on a top surface of a semiconductor substrate, the patterned layer of photoresist including an opening, the opening having a curved side surface smoothly joined to an exposed top surface of the patterned layer of photoresist; etching the top surface of the semiconductor substrate through the opening in the patterned layer of photoresist to form a straight-walled recess, the straight-walled recess having a side surface substantially perpendicular to the top surface of the semiconductor substrate; and after the straight-walled recess is formed, dry etching the patterned layer of photoresist and the semiconductor substrate, where the dry etching gradually thins the patterned layer of photoresist along a surface profile of the patterned layer of photoresist while transforming the straight-walled recess into a funnel-shaped recess, the funnel-shaped recess includes a straight-walled bottom portion and a curved top portion having a curved sidewall gradually converging toward and smoothly joined to the straight-walled bottom portion, and the curved top portion encloses a volume that is substantially greater than a volume enclosed by the straight-walled bottom portion.