A printhead having self-aligned holes

摘要

A printhead (18) having self-aligned holes through a substrate (28) to form a fluid feed passage is provided. The printhead comprises a silicon wafer (28) having a first side, including a row of chambers (30) and a second side, including a ground surface; a plurality of self-aligned holes disposed along a first side of the row of chambers (30) and a plurality of self-aligned holes disposed along a second side of the row of chambers; and extending from the first side of the silicon wafer (28) to the second side, wherein each self-aligned hole (36) is smaller at the first side of the silicon wafer (28) than at the second side of the silicon wafer (28) to form a retrograde profile angle; a drop forming mechanism (34) in the chamber (30); a nozzle plate (31) proximate to the drop forming mechanism (34); and a source of fluid for supplying fluid to the hole (36).