Hewlett-packard Company

John E Turner

Clifford I Drowley

Theodore I Kamins

Frank R Bryant

Martin P Scott

Jung Lin

Yvonne H Keller

A thin-film print head is provided that includes at least one MOSTFT transistor, at least one resistor, a conductive line between the transistor and resistor. External interconnects between the internal circuitry of print head and external driver circuitry are provided. The thin-film print head device is adjacent to an ink barrier and an orifice plate that together define the firing chamber. Each firing chamber has associated with it a respective thin-film resistor of the print head that is selectively driven by a respective transistor. The transistor includes a source, a gate, a channel, and a drain, wherein the source, channel, and drain are formed by a first polysilicon layer. The MOSTFT transistor selectively drives the resistor with sufficient current to vaporize ink in the chamber and eject ink therefrom. The MOSTFT transistor allows the print head to be manufactured on a relatively inexpensive, non-silicon substrate or a less expensive silicon substrate, due to the less restrictive criteria for the substrate material required by MOSTFT transistors. The substrate may also comprise a material that provides enhanced thermal conductivity to act as a substantial heat sink for the print head.

Thin-film print head for thermal ink-jet printers

A method of forming interconnects for submicron integrated circuits that allows use of titanium-tungsten as the interconnect material. The inherent instability of titanium-tungsten to oxidation is addressed by a nitridation process that includes exposing the interconnect to an ambient containing nitrogen (NH.sub.3) at an elevated temperature. Typically, the process is a rapid thermal anneal. A local interconnect may be formed, whereafter an insulating layer can be deposited at a high temperature without causing oxidation within the local interconnect that would adversely affect the resistivity of the material.

Nitridation of titanium-tungsten interconnects

Very shallow electrical junctions may be formed in an oxide free surface of a semiconductor by introducing an inert or reducing gas into a vacuum processing chamber, heating the semiconductor to between 750.degree. C. and 1100.degree. C., introducing a dilute solution of a dopant gas into the chamber, and exposing the semiconductor to the gases for about 0.5 to about 100 minutes, preferably between 10 and 30 minutes. A relatively wide range of surface dopant concentrations may be achieved thereby with dopant concentration controlled independent of junction depth. Non-oxide free semiconductor surfaces may be made oxide free by first heating the semiconductor surface in the presence of the reducing gas. This technique provides uniform surface dopant concentrations and is suitable for the formation of junctions in deep trenches and other features having high aspect ratios.

Method of forming doped shallow electrical junctions

Apparatus for forming shallow electrical junctions

A method of fabricating a semiconductor device to retard diffusion of a dopant from a center active region into adjacent regions. The center active region is epitaxially formed by selectively increasing and decreasing an introduction of diffusion-suppressing material, preferably germanium, into a semiconductor material, preferably silicon, so that a vertical profile of the content of the diffusion-suppressing material is such that outdiffusion of a dopant is minimized. One embodiment of the tailoring is to increase the concentration of the diffusion-suppressing material at both of the opposed sides of a base region of a bipolar transistor, thereby providing concentration peaks at the interfaces of the base region with collector and emitter regions. The concentration of germanium in a Si.sub.1-x Ge.sub.x layer is such that the value x is within the range 0.08 to 0.35 and optimally within the range 0.15 to 0.31. The dopant, preferably boron, also has a tailored concentration profile to minimize outdiffusion. A thinner, more highly doped active region is thereby achieved.

Growing community of inventors

Woodside, CA, United States of America

John E Turner