Category: Glossary

The resistance to a current flow along the surface of an insulator material. Measure in ohms-cm.

The property of a liquid which causes the surface to pull into the smallest area for a maximum volume, hence, drops are spherical. The fact that water drops on a wax surface do not spread out due to surface tension. If a wetting agent were to be added to the water the round droplet would spread out into a film because of the lowered surface tension.

An LED that emits light from its flat surface rather than its side. Simple and inexpensive, with emission spread over a wide angle.

A chemical added to any substance to lower its surface tension.

One trillion.

An IC mounted on a TAB site.

The process where silicon chips are joined to patterned metal traces (leads) on polymer tape to form inner leads bonds and subsequently the leads are attached to the next level of the assembly, typically a substrate or board, to form outer lead bonds. TAB is the technique of interconnecting silicon with beam bonding as opposed to wire bonding.

A BGA package on a copper polyimide base like TAB, except TAB leads are replaced by an area array ball grid for interconnects. A stiffener is added to ensure flatness for the mass reflow assembly process.

Abbreviation for second.

Society of Automotive Engineers.

The change of direction of light rays or photons after striking small particles. It may also be regarded as the diffusion of a light beam caused by the non-homogeneity of the transmitting material.

The transfer of a pattern onto a surface by forcing a suitable material through a screen with a squeegee.

To convert an epoxy into a fixed or hardened state by chemical or physical action through polymerization.

The shear force required to break a specimen divided by its cross-sectional area; the force being applied parallel to the cross-sectional area.

The reading of a material’s hardness on a durometer, the scale of which is 0-100, used on elastomers and other flexible materials. Consists of a pin point depression into the material, the material being at least 100 mils thick. A Shore A reading of 80 equal a Shore D reading of 30.

The reading of a material’s hardness on a durometer similar to the Shore A durometer, the scale of which 0-100, used on rigid and semi-rigid materials. Consist of a pin point depression into the material. Both the Shore A and Shore D instruments are made by the Shore Instrument Manufacturing Company, Inc., Jamaica, NY.

An unwanted connection between conductor paths.

The decrease in volume, or contraction, of a material by the escape of any volatile substance, or by a chemical or physical change in the material.

Generally used in detectors. Good for short wavelengths only (e.g., < 1000 nm).

Abbreviation for International System of Units, commonly known as the metric system,