1. Field of the Invention
The present general inventive concept relates to a method of manufacturing an inkjet printhead, and an inkjet printhead manufactured using the method, and more particularly, to a method of manufacturing an inkjet printhead in which formation of a reaction layer at the bottom of a nozzle layer is prevented, and an inkjet printhead prepared using the method.
2. Description of the Related Art
Inkjet printheads eject tiny droplets of print ink onto a predetermined portion of a to-be-printed sheet so as to produce a predetermined color image, and are categorized into thermal driving type inkjet printheads and piezoelectric driving type inkjet printheads according to an ejection mechanism of ink droplets. As for the thermal driving type inkjet printheads, ink droplets are ejected by an expansion force of bubbles generated when a heat source is applied to the generated bubbles within the ink. As for the piezoelectric driving type inkjet printheads, ink droplets are ejected by a pressure to ink due to a deformation of a piezoelectric device using the device. FIG. 1 is a cross-sectional view of a conventional thermal inkjet printhead.
Referring to FIG. 1, the conventional thermal driving type inkjet printhead includes a substrate 10, a channel forming layer 20 formed on the substrate 10, and a nozzle layer 30 formed on the channel forming layer 20. The substrate 10 has an ink feed hole 51, and the channel forming layer 20 has an ink chamber 53 that can be filled with ink and a restrictor 52 connecting the ink chamber 53 to the ink feed hole 51. The nozzle layer 30 has at least one nozzle 54 through which ink is ejected from the ink chamber 53. On the substrate 10, at least one heater 41 is mounted to heat ink within the ink chamber 53 and at least one electrode 42 is mounted to supply a current to the heater 41.
An ink droplet ejection mechanism of the conventional thermal driving type inkjet printhead will now be described in detail. Ink is fed from an ink container (not illustrated) into the ink chamber 53 through the ink feed hole 51 and the restrictor 52. The ink filled within the ink chamber 53 is then heated by the heater 41 which is formed of a heat-generating resistance and which is located within the ink chamber 53. Once the ink boils, ink generates bubbles, and the generated ink bubbles apply pressure to the ink filled within the ink chamber 53. Therefore, the ink within the ink chamber 53 is ejected through the nozzle 54 to the outside of the ink chamber 53 in the form of droplets.
A conventional inkjet printhead has a protrusion 55, hereinafter referred to as a reaction layer, at the bottom of a nozzle layer, as illustrated in FIGS. 3A and 3B. The reaction layer is formed when a photoresist that is used to form an ink channel is mixed or reacts with a photoresist composition that is used to form a nozzle layer, and degrades the ejection performance of the ink.