Micro-fluid ejection device and method for assembling a micro-fluid ejection device by wafer-to-wafer bonding

Abstract

A micro-fluid ejection device is assembled by wafer-to-wafer bonding at a temperature below about 150° C. a first silicon oxide layer of a first wafer, having flow features patterned in the first silicon oxide layer on an actuator chip in a first silicon substrate of the first wafer, to a second silicon oxide layer of a second wafer, defining a nozzle plate on a second silicon substrate of the second wafer. Nozzle holes are formed in the nozzle plate in alignment with actuator elements of the actuator chip of the first wafer either before or after bonding the first and second wafers together. The second silicon substrate of the second wafer is used as a handle and then removed from the silicon oxide layer of the second wafer after bonding the first and second wafers together.

Description

[0001]This application claims priority and benefit as a division of U.S. patent application Ser. No. 12 / 266,613, filed Nov. 7, 2008, and having the same name.BACKGROUND[0002]1. Field of the Invention[0003]The present invention relates generally to micro-fluid ejection devices and, more particularly, to a micro-fluid ejection device and a method for assembling the micro-fluid ejection device by wafer-to-wafer bonding.[0004]2. Description of the Related Art[0005]Micro-fluid ejection heads or devices are broadly useful for ejecting a variety of fluids including inks, cooling fluids, pharmaceuticals, lubricants and the like. One widely-practiced use of a micro-fluid ejection device is as an inkjet printhead in an inkjet printer. The primary components of the inkjet printhead are an actuator chip, a nozzle plate attached to or integrated with the actuator chip, and a flexible circuit for electrically connecting the actuator chip to the printer during use. The actuator chip is typically m...

AI Technical Summary

Benefits of technology

This approach improves the precision and reliability of nozzle hole placement, size, and shape, enabling better print quality by using a silicon oxide nozzle plate that is not subject to swelling or material mismatch issues, and allows for the use of a wider range of solvents.

Problems solved by technology

Also, since silicon is not an organic polymer, but an inorganic material, the silicon nozzle plate does not constrain the micro-fluid ejection device to use only with an aqueous system nor is it subject to swelling.

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