Singulating ejection chips for micro-fluid applications

Abstract

A micro-fluid ejection head has multiple ejection chips joined adjacently to create a lengthy array across a media to-be-imaged. The chips have fluid firing elements arranged to seamlessly stitch together fluid ejections from adjacent chips. Each chip aligns with other chips at peripheral regions having edge tolerances closer than elsewhere along the periphery. The tolerances result from both etching and dicing during chip singulation. Etching occurs at the areas of alignment. Dicing occurs elsewhere. Etching techniques include deep reactive ion etching or wet etching. It cuts a planar periphery through an entire thickness of the wafer. The etching may also occur simultaneously with etching a fluid via. Dicing techniques include blade, laser or ion beam. It cuts an entire remainder of the periphery connecting the portions already etched to free single chips from the wafer. Edge tolerances, planar shapes, dicing lines, etch patterns, and wafer layout provide still further embodiments.