Patent ID: 8377319

Claim:
A method of forming a device, comprising: etching a recess into a first surface of a nozzle layer of a multi-layer silicon substrate, wherein the multi-layer silicon substrate has a handle layer and a silicon oxide layer between the nozzle layer and the handle layer, and wherein the recess includes tapered sidewalls and a bottom surface having a first width measured in a direction parallel to the first surface; securing the first surface of the nozzle layer to a substrate having a chamber such that the recess is fluidly coupled to the chamber; after the securing, removing a portion of the multi-layer silicon substrate from an exposed side of the multi-layer silicon substrate, including at least the handle layer of the multi-layer silicon substrate; and etching a portion of the nozzle layer, from an exposed side of the nozzle layer using the silicon oxide layer as a mask, the etching including an anisotropic etch of a region on the exposed side having a second width measured in the direction parallel to the first surface, the second width greater than the first width such that portions of the tapered sidewalls of the recess are removed and the chamber is fluidly coupled to the atmosphere through the recess.