METHOD OF FORMING NOZZLE FOR INJECTORS AND METHOD OF MANUFACTURING INK JET HEAD

摘要

A cross-sectionally stepped nozzle (21) having a nozzle portion (21a) of a smaller cross-sectional area provided at a front part with respect to the jetting direction and a nozzle portion (21b) of a larger cross-sectional area provided at a rear part with respect thereto is formed by etching a silicon wafer (200) on which a nozzle plate (2) is to be formed. A method of forming the nozzle (21) comprises forming a resist film (210) on a surface (200a) of a silicon wafer (200), subjecting this resist film (210) to patterning by half etching and patterning by full etching, subjecting the resultant product to anisotropic dry etching by ICP discharge to form a groove in a full etched portion, removing the resist film on the half etched portion by etching, and subjecting the same portion to anisotropic dry etching again by ICP discharge. Consequently, a nozzle having a stepped cross-sectional shape and a large effect in aligning the direction of a pressure, which is applied from the side of a cavity to the nozzle, parallel to the axis of the nozzle can be formed simply and efficiently on a single-crystal silicon substrate.