PEEK™

Polyaryletherketone PEEK™ Polymer for
TELECTRONICS INDUSTRY

The PEEK™ telectronics market may be very broadly classified into three key areas, namely: The production of semiconductor materials, electrical and electronic applications (domestic and business), and wire and cable production. The Polyaryletherketone PEEK™ polymer is the material of choice for these applications due to an unparalleled combination of physical properties, which are subsequently discussed for application areas.

SEMICONDUCTOR PRODUCTION
PEEK™ polymer is increasingly used for the transport and storage of semiconductors during production. Historically. the material of choice has been carbon fibre reinforced polypropylene. However, with increasing specification of semiconductor wafers it has become clear that polypropylene carriers have met their limitation. Production is adversely affected by wear particles, outgassing, doping of semiconductors by the ionic extractables and poor mechanical properties of the carrier material.

Wear particles are produced by contact between the carrier material and other surfaces.
Independent tests by industry experts have shown that PEEK™ polymer sheds extremely low levels of wear particles (ASTM-D-1044) compared to other thermoplastics.

Outgassing may be defined as the emission of volatile compounds, which may subsequently condense on wafers causing contamination. The testing standard ASTM-Fl227-89 measures the Collective Volatile Condensed Material (CVCM) mass at 20°C. Although PEEK™ polymer and polypropylene carriers both meet SEMI specifications in this test, PEEK™ polymer has a lower CVCM value. In addition PEEK™ polymer wafer carriers have a tighter tolerance and retain their dimensional stability over a much longer service-lifetime, or temperature range (UL Continuous Use Temperature. CUT ~ 260°C). The excellent mechanical properties of PEEK™ polymer over a wide temperature range, increase the use of automated transfer production systems.

Semiconductor wafer carriers often experience aggressive chemical environments at elevated temperatures. Over a service-lifetime these materials may be leached of ionic species, which have been shown to diffuse into the semiconductors, acting as doping agents, PEEK™ polymer has extremely tow levels of ionic extractables.

ELECTRICAL AND ELECTRONICS
The electrical properties of the Polyaryletherketone PEEK™ polymer are typical of the generic class of thermoplastic materials. However, the number and diversity of electrical and electronic applications of PEEK™ polymer reflect the all-round high performance of the material. Therefore, PEEK™ polymer may form the insulating-housing for devices that operate in high-dose radiation, chemically aggressive or high temperature environments.

WIRE AND CABLE
The wire and cable coating industry is dependent on the processability of polymeric materials and does not generally use high performance thermoplastics. However, due to the ease of process and the high quality of product. PEEK™ polymer is increasingly used in demanding wire and cable applications.

Often, wires and cables used in potential fire risk situations are insulated using PEEK™ polymer, due to the outstandingly low values of flammability and smoke emission for a thermoplastic material. Independent studies by the Underwriters laboratory have shown that PEEK™ polymer has a V-0 rating for a 1.45 mm thick sample white NBS smoke chamber testing of a 3.20 mm thick sample shows no measurable emissions after 4 minutes of ignition.

ELECTRICAL INSULATORS AND HOUSINGS
Lemo began using the Polyaryletherketone PEEK™ polymer to insulate and house hermaphroditic electrical connection units for military applications. Due to the outstanding success of the devices in demanding mechanical and thermal situations, Lemo expanded the use of PEEK™ polymer to form connectors, which feature in devices for communications, medical, aerospace and research-instruments.

Although each of the individual specialist application areas requires specific properties of the insulator material, a common feature, which is key to many of these markets is the ability of PEEK™ polymer to retain a high degree of the electrical resistance and mechanical strength close to the melting point of 343°C.

ELECTRICAL CONNECTORS
Feme Spa is a major producer of electrical components such as switches, connectors and relays. They have vast experience in the design and manufacture of military devices and fully appreciate the demanding requirements of this sector and the need for absolute reliability.

The Polyaryletherketone PEEK™ polymer was chosen to replace a polyamideimide material for a particularly demanding connector system used by NATO forces in the field (American Connector Standard MIL-0-26482). Although both materials displayed sufficient mechanical and thermal properties for this particular application, PEEK™ polymer exhibited superior resistance to the chemical environments and the fatigue loading encountered. Laboratory testing also showed that the 58 metal inserts which are added to the moulding after process are more successfully retained in continuous 'application then removal' experiments by PEEK™ polymer components. The use of the Polyaryletherketone PEEK™ polymer for such devices also removes the requirement of post-process annealing.

WAFER BASKET
The process of manufacturing semiconductors consists of more than one hundred stages, during which hundreds of copies of an integrated circuit are formed on a single wafer. Generally, the process involves the formation of up to twenty layers of material on a semiconductor wafer substrate.
The layering process creates areas of electrically active and in-active material on the surface of the wafer. Due to the precision and accuracy of these processes many of the stages are fully automated and the wafers are transported in wafer carrier baskets.

Mitsui chose the Polyaryletherketone PEEK™ polymer for carrier baskets, used in semiconductor wafer fabrication as a replacement for fluoropolymer materials. In addition to superior mechanical performance over a wide temperature range, PEEK™ polymer offered lower levels of outgassing, ionic extractables, wear particles and improved dimensional stability which have been proved to be critical to the device yield.

WIRE AND CABLE INSULATION
The extensive use of the Polyaryletherketone PEEK™ polymer as insulation in the wire and cable industry is a testimony to the ease of process and the physical properties of the material. Perhaps the most demanding of these applications is the insulation of reinforced cables used in the oil industry. BICC (UK) chose PEEK™ polymer for this application as they required a material, which was electrically resistant and mechanically sound up to temperatures in excess of 200°C.

The wires and cables used in mass transit systems and commercial aircraft must have extremely tow values of flammability and smoke emission to reduce the hazard to passengers and crew in the event of a fire. PEEK™ polymer is used as an insulating sheath in such applications as it has been shown to be the safest practicable construction material. Independent testing has shown that PEEK™ polymer has a UL94 rating of V-0 for a 1.45 mm thick sample whilst NBS smoke chamber measurements show no appreciable smoke emission after 4 minutes ignition.

Top