Thermal inkjet printhead structure and method for making the same
US5159353A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1991 |
| Grant date | Oct 27, 1992 |
| Priority date | — |
| Expiry date | Jul 2, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49401
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An improved thermal inkjet printhead having MOSFET drive transistors incorporated therein. The gate of each MOSFET transistor is formed by applying a layer of silicon dioxide onto a silicon substrate, applying a layer of silicon nitride onto the silicon dioxide, and applying a layer of polycrystalline silicon onto the silicon nitride. Portions of the substrate surrounding the gate are oxidized, forming field oxide regions. Drain and source regions are then conventionally formed, followed by the application of a protective dielectric layer onto the field oxide, drain, source, and gate. A resistive layer is deposited on the dielectric layer and directly connected to the source, drain, and gate. A conductive layer is deposited on a portion of the resistive layer, ultimately forming both covered and uncovered regions thereof. The uncovered region functions as a heating resistor, and the covered regions function as electrical contacts to the transistor and resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.