Thermal ink-jet printhead with a suspended heating element in each ejector
AssigneeXerox Corporation
InventorJoel A. Kubby
Life of this patent
Estimating the term…
Abstract
In a thermal ink-jet printhead, a set of heating elements are formed in the main surface of a semiconductor chip. Channels are formed by etching within the semiconductor chip underneath each of the heating elements, thereby exposing two main sides of each heating element within each ejector. Because two main surfaces of the heating element are accessible to liquid ink in each ejector, efficiency and thermal characteristics of the printhead are improved.
Claims11
A method of making a thermal inkjet printhead, the printhead comprising at least one ejector, the ejector including a heating element for vaporizing liquid ink adjacent thereto, comprising the steps of:
- providing a semiconductor chip including a functional layer disposed over a main surface of an etchable layer, the heating element being defined in a portion of the functional layer;
- creating a first opening in the functional layer adjacent the heating element, the first opening exposing a portion of the etchable layer;
- etching an area of the etchable layer, the area encompassing the first opening and the heating element, thereby forming a cavity in the etchable layer under the heating element;
- and
- providing a complementary structure over the main surface of the etchable layer, the complementary structure defining a channel therein, whereby the portion of the functional layer including the heating element is suspended between the cavity and the channel.
A method of making an ejector for a thermal ink-jet printhead, comprising the steps of:
- providing a semiconductor chip including a functional layer disposed over a main surface of an etchable layer, wherein a heating element is defined in a portion of the functional layer;
- providing a first opening in the functional layer, the first opening exposing a portion of the etchable layer;
- and
- etching an area of the etchable layer, thereby forming a channel in the etchable layer extending from the first opening under a portion of the functional layer, the channel extending under the heating element, thereby forming an ink passageway for the ejector.
Dependencies are inferred from the claim text.