Fluorosilicate glass (FSG) is a
glass material composed primarily of
fluorine
Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as a highly toxic, pale yellow diatomic gas. As the most electronegative reactive element, it is extremely reacti ...
,
silicon and
oxygen. It has a number of uses in industry and manufacturing, especially in semiconductor fabrication where it forms an insulating
dielectric. The related fluorosilicate glass-ceramics have good mechanical and chemical properties.
Semiconductor fabrication
FSG has a small
relative dielectric constant (
low-κ dielectric In semiconductor manufacturing, a low-κ is a material with a small relative dielectric constant (κ, kappa) relative to silicon dioxide. Low-κ dielectric material implementation is one of several strategies used to allow continued scaling of micr ...
) and is used in between metal
copper interconnect
In semiconductor technology, copper interconnects are interconnects made of copper. They are used in silicon integrated circuits (ICs) to reduce propagation delays and power consumption. Since copper is a better conductor than aluminium, ICs usi ...
layers during
silicon integrated circuit
An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, usually silicon. Large numbers of tiny ...
fabrication
Fabrication may refer to:
* Manufacturing, specifically the crafting of individual parts as a solo product or as part of a larger combined product.
Processes in arts, crafts and manufacturing
*Semiconductor device fabrication, the process used t ...
process. It is widely used by
semiconductor fabrication plants on geometries under 0.25 microns (μ). FSG is effectively a
fluorine
Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as a highly toxic, pale yellow diatomic gas. As the most electronegative reactive element, it is extremely reacti ...
-containing
silicon dioxide (κ=3.5, while κ of undoped silicon dioxide is 3.9).
FSG is used by
IBM.
started using Cu metal layers and FSG on its 1.2 GHz
Pentium processor at 130 nm complementary metal–oxide–semiconductor (
CMOS
Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss", ) is a type of metal–oxide–semiconductor field-effect transistor (MOSFET) fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSFE ...
). Taiwan Semiconductor Manufacturing Company (
TSMC) combined FSG and copper in the
Altera APEX.
Fluorosilicate glass-ceramics
Fluorosilicate
glass-ceramics are crystalline or semi-crystalline solids formed by careful cooling of molten fluorosilicate glass. They have good mechanical properties.
Potassium fluororichterite based materials are composed from tiny interlocked rod-shaped
amphibole
Amphibole () is a group of inosilicate minerals, forming prism or needlelike crystals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Its IMA symbol is A ...
crystals; they have good resistance to chemicals and can be used in
microwave ovens.
Richterite
Richterite is a sodium calcium magnesium silicate mineral belonging to the amphibole group. If iron replaces the magnesium within the structure of the mineral, it is called ferrorichterite; if fluorine replaces the hydroxyl, it is called fluo ...
glass-ceramics are used for high-performance
tableware.
Fluorosilicate glass-ceramics with sheet structure, derived from
mica
Micas ( ) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into extremely thin elastic plates. This characteristic is described as perfect basal cleavage. Mica is ...
, are strong and machinable. They find a number of uses and can be used in high vacuum and as dielectrics and precision ceramic components. A number of mica and mica-
fluoroapatite
Fluorapatite, often with the alternate spelling of fluoroapatite, is a phosphate mineral with the formula Ca5(PO4)3F (calcium fluorophosphate). Fluorapatite is a hard crystalline solid. Although samples can have various color (green, brown, bl ...
glass-ceramics were studied as
biomaterials.
See also
*
Fluoride glass
*
Glass
*
Silicate
In chemistry, a silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is al ...
References
Silicates
Glass compositions
Integrated circuits
Semiconductor fabrication materials
Biomaterials
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