An electrically conductive adhesive is a glue that is primarily used for electronics. The electric conductivity is caused by a component that makes ca. 80% of the total mass of an electrically conductive adhesive. This conductive component is suspended in a sticky component that holds the electrically conductive adhesive together. The particles of the conductive component are in contact to each other and in this way make electric current possible.

Composition

The conductive component can be

silver Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. ...

nickel Nickel is a chemical element; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive, but large pieces are slo ...

copper Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...

graphite Graphite () is a Crystallinity, crystalline allotrope (form) of the element carbon. It consists of many stacked Layered materials, layers of graphene, typically in excess of hundreds of layers. Graphite occurs naturally and is the most stable ...

. Other conductive materials are possible but unusual. The adhesive component can be a varnish, synthetic resin, or

silicone In Organosilicon chemistry, organosilicon and polymer chemistry, a silicone or polysiloxane is a polymer composed of repeating units of siloxane (, where R = Organyl group, organic group). They are typically colorless oils or elastomer, rubber ...

. Variations in conductive component's type and concentration change the resistivity of the adhesive. A typical silver-based conductive adhesive such as that made by Electrolube contains ingredients in the following proportions: They are specifically formulated in paste (micro-particles) for use in

scanning electron microscopy A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that ...

(SEM) and other electron optical applications find use in producing or repairing

printed circuit board A printed circuit board (PCB), also called printed wiring board (PWB), is a Lamination, laminated sandwich structure of electrical conduction, conductive and Insulator (electricity), insulating layers, each with a pattern of traces, planes ...

(PCB) tracks, to paint-on an electrical screen, or to make electrical connections to non-solderable surfaces.

Applications

* One could fix a defective conductor on a printed circuit board using an electrically conductive adhesive. In the same way, one could fix a defective rear windscreen heater on a car using an electrically conductive adhesive. * If just a small current is needed, a temperature-sensitive electronic element can be electrically connected to a circuit using an electrically conductive adhesive instead of soldering. * Electrically conductive adhesives can be used to paint the inner surface of plastic boxes containing electronic devices. This makes a Faraday cage saving the internal components from

electromagnetic radiation In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength ...

. * Electrically conductive adhesives are used in SEM to fix and ground the sample to avoid electrostatic charging of the surface.

Composition

Applications

References

Further reading