Silicon Substrate Nozzle Manufacturing via Etching and Bonding

The patent applies preliminary action by forming the nozzle channels through the substrate before reducing the substrate thickness. Specifically, the method forms first nozzle channels and second nozzle channels connected thereto in the silicon substrate by etching both faces of the substrate, then reduces the substrate thickness to a predetermined value. This sequence ensures that the nozzle structures are established while the substrate still has sufficient thickness to prevent cracking and chipping during the thickness reduction process.

The patent applies preliminary action by performing the thickness reduction operation after nozzle channel formation but before forming the protective layer. The method reduces the substrate thickness to a predetermined value, then forms an ink-resistant protective layer by thermal oxidation. By this timing, the substrate is thin enough to allow uniform protective layer formation but the nozzle channels are already established, preventing the need for complex manufacturing processes while ensuring uniform protective layer deposition.

The patent applies the taking out principle by removing the cooling function from the etching process environment. Instead of introducing helium gas into the etching chamber to cool the nozzle plate, the method forms nozzle channels by etching both faces of the substrate without requiring gas cooling during etching. This eliminates the problem of gas flowing to the processed face and preventing etching, while still achieving accurate nozzle channel formation through the dual-face etching approach.