Patent attributes
Techniques are provided for making a funnel-shaped nozzle in a substrate. The process can include forming a first opening having a first width in a top layer of a substrate, forming a patterned layer of photoresist on the top surface of the substrate, the patterned layer of photoresist including a second opening, the second opening having a second width larger than the first width, reflowing the patterned layer of photoresist to form curved side surfaces terminating on the top surface of the substrate, etching a second layer of the substrate through the first opening in the top layer of the substrate to form a straight-walled recess, the straight-walled recess having the first width and a side surface substantially perpendicular to the top surface of the semiconductor substrate.

