BALL GRID ARRAY: (BGA) A surface-mount microelectronic package that uses an array of solder balls to provide electrical interconnect and physical mount to the next level of package such as a printed circuit board.
BIOCHIP: A miniature silicon, glass or plastic piece consisting of a large number of microstructures containing special probes of biologically active molecules to be used as an analytical and diagnostic tool. For example, the biochip makes it possible to identify very large numbers of genes or proteins (protein chip) in relative short time.
BIOMEMS: Biological or Biomedical MicroElectroMechanical Systems are microsystems with applications for biological, biomedical and analytical instrumentation fields. Examples of BioMEMS include devices and microsystems for drug delivery, DNA/protein analysis, molecular manipulation/assembly, microfluidics, as well as biosensors and micro total analysis systems.
CONTACT RESISTANCE: Excess electrical resistance in series with the bulk conductor resistance of two contacting electrical conductors arising from the nature of contact geometry and properties of the contact surfaces.
CREEP: Non-recoverable deformation proceeding at relative low strain rates, usually associated with high temperature to allow sufficient rates of diffusion.
ENCAPSULATION: Sealing up or covering a circuit or electromechanical element for mechanical and environmental protection.
ETCHING: Process by which material is removed from the wafer in a pattern already transferred lithographically. This may be achieved chemically in a process referred to as “wet” etching using chemical solutions, or with a “dry” etch in a plasma, where a controlled gas flow is ionized and reacts with surface material on the wafer with a physical bombardment of particles.
FAILURE MECHANISM: A physical, chemical or other processes that leads to failure. Some examples of failure mechanisms in MEMS include: stiction, creep, fatigue, wear, dielectric charging, and breakdown.
GETTER: Getters are materials which, when properly activated, can remove traces of gas in a vacuum package by reacting with gas molecules.
LAB-ON-A-CHIP: LOC. A miniature analytical system that contains microfluidic channels to allow minute liquid or gas to be separated and analyzed by integrated microdevices, including pumps, valves, microfluidic controllers, and detectors.
MEMS: MicroElectroMechanical System. An enabling microfabrication technology that uses manufacturing processes similar to that of semiconductors and integrated circuits to create discrete or integrated microdevices, such as mechanical structures, microsensors, microactuators, and circuitry on a substrate material including silicon, glass or ceramic. In referring to this technology, MEMS is the term commonly used in North America whereas Microsystem Technology (MST) and Micromachines are commonly used in Europe and Japan respectively.
PASSIVATION: The formation of an insulation layer over the surface of an microelectronic element to serve as a barrier to further oxidation or corrosion. It also protects the surface from contaminants, moisture, or particles.
RIE: Reactive Ion Etch. Plasma process technology for etching pre-patterned structures into substrates.
SHEET RESISTANCE: The electrical resistance of a thin sheet of material with uniform thickness as measured across opposite sides of a unit square pattern. It is expressed in ohms per square.
VACUUM SEALING: A process of encapsulation of MEMS device in vacuum. The dealing may be achieved in wafer fabrication by a film deposition process in vacuum to seal a chamber that is created with the removal of a sacrificial layer. Alternately, the vacuum sealing of MEMS device can be done by wafer capping in vacuum.
YOUNG’S MODULUS: A measure of the stiffness of a material in the elastic range. It is determined from the slope of a stress-strain curve obtained during tensile tests on a sample of the material. Young’s Modulus is also known as Modulus of Elasticity.
The above terms and definitions were contributed from a starter glossary produced by the MEMS Industry Group.