PBN crucibles BORALLOY® Pyrolytic Boron Nitride (pBN)

Highest quality material from the market leader Advanced Ceramics Corp. (formerly UNION CARBIDE).

• complete range of standard PBN crucibles compatible with cells fromall major MBE equipment suppliers
• single and double wall crucibles (especially for evaporation of Al)
• hot-lip PBN/PG crucible for reduced defects in MBE grown layers
• custom made crucibles for MBE, LEC ...
• made to order PBN parts

HOT-LIP PBN/PG CRUCIBLES REDUCE DEFECTS IN MBE GROWN LAYERS

These patented MBE crucibles employ the infrared (IR) absorption and anisotropic thermal conduction characteristics of pyrolytic graphite (PG) in concert with the purity, chemical inertness and high temperature stability of pyrolytic boron nitride (PBN) to optimize axial thermal profiles for enhanced control over source molecular flux.

PG is an extremely efficient IR absorber and the thermal conductivity anisotropy provides outstanding heat transfer and thermal leveling characteristics. PG is deposited on the top O.D. of a PBN crucible and then encapsulated with PBN thus isolating the PG chemically from the melt and surrounding and electrically from the heater filaments.

Hot-Lip MBE crucibles:

• Reduce radial growth rate variation
• Dramatically reduce defect density to levels equivalent to those produced from dual filament cells.

Pyrolytic Boron Nitride

Boralloy Pyrolytic Boron Nitride (PBN) is a nontoxic, nonporous compound which is exceptionally pure by virtue of its synthesis from a vapor in a patented, high temperature, low pressure process. It can be deposited or machined into a limitless number of shapes including plates, wafers, rods, tubes, crucible and boats.

PBN has several characteristics of interest to design engineers- most notably its strong directional, thermal and mechanicial properties. Engineers can take advantage of this anisotrophy when designing hardware for specific applications.

Applications and potential applications for PBN abound in semiconductor processing, microwave electronics, nonferrous metallurgy and pharmaceuticals.

Pyrolytic Graphite ( PG )

• high purity PG made by CVD process
• crucibles for e-beam evaporation
• made to order parts

Pyrolytic graphite (PG) is an ultra-pure CVD product which is near theoretical density and is extremely anisotropic. Mechanical, thermal and electrical properties are superior to conventional graphites.

PG is available as plate, free standing shapes as an impermeable coating on graphite and other substrates.

Advanced Ceramics Corporation also offers a special form of PG that exhibits exceptional, in plane thermal conductivity that approaches the performance of diamond. This form of PG provides many solutions to thermal management problems.

PBN Coated Graphite

Boralloy PBN is also used as a coating on graphite substrates. Examples include RF susceptors, heat shields, nozzles and resistance heaters. It has also been applied to other substrates such as ceramic fibers and carbon-carbon composites. Please inquire about your specific coating needs.

Other Graphite Coatings

In addition to PBN and PG coatings, Graphite can also be used with silicon carbide and a variey of metal carbides.

The silicon carbide can be provided as a surface conversion (CVR) or a vapor deposited coating (CVD). The CVR version is commonly used in chemical and metallurgical applications, while the CVD process has uses in the high purity semiconductor industry.

Niobium carbide, tantalum carbide, titanium carbide and zirconium carbide are also available as protective coatings on graphite.

The outstanding characteristics of these pyrolytic carbide coatings are their extreme hardness, excellent corrosion resistance, high melting points and resistance to hydrogen attack above 2500 Celsius.

Wide variety of Standard Substrate manipulators designed for use in MBE

Substrate Manipulators for 2" to 4" wafers and temperatures starting from 800°C to more than 1.400°C are available

Annealing oven

Annealing Oven has precise electronic temperature regulation and inert gas handling combined with dry vacuum pumping. Standard Version: RT - 450 °C, temperature stability 2°, heating ramp about 30° / sec.