Gas to solid Components made of pyrolytic boron nitride & graphite with Chemical Vapour Deposition

With our Gas to Solid process, years of experience and certified quality assurance processes we can accommodate an extremely wide range of customers’ wishes and needs in the manufacture of components made of pyrolytic boron nitride.

Gas to Solid means that, starting out from different gases, we vaporise these under vacuum at high temperature and deposit the gaseous components on a mould or a component as a solid (pyrolytic boron nitride/pyrolytic graphite) in extremely thin layers. In this way we can obtain the required solids from gas in the highest purity and equip these with individual properties.

Method/process: Chemical Vapour Deposition

1: Graphite mandrels
2: Boron halides (BF3 and BCI3), ammonia (NH3) and nitrogen (N2) or hydrocarbons (boron halide, NH3 and N2)
3: Heating
4: Pumps
5: Gas scrubbers

 

In the CVD process we use highly pure gases such as boron halide (BF₃ and BCl₃), ammonia  (NH₃) and nitrogen (N₂) or hydrocarbons.

These gases are brought to reaction at high temperature and coat the graphite mandrels installed in the reactor under a controlled atmosphere. This thin coating is applied to mandrels produced specially according to customers’ specifications. The form is determined by the graphite negative.

Depending on the type of graphite, the coating can be removed following the process (free-standing PBN component) or a coating is produced on the graphite (coating).

The surfaces of the components are then processed according to the customer’s specifications before these are cleaned, packed and then made ready for shipping.

Flexible, highly resistant, pure: the properties of CVT’s CVD products

The highest manufacturing standards are complied with in the manufacture of all of CVT’s products which are manufactured by means of Chemical Vapour Deposition. Only in this way can the products made of pyrolytic boron nitride or graphite fulfil the high requirements which apply when in use. 

HIGH CHEMICAL STABILITY

Through the purity of the products and the precision of physical manufacture we achieve optimum values in terms of chemical stability, thus guaranteeing you process reliability. 

HIGH PURITY

The CVD products which we produce are of extraordinary purity, which is key to the chemical processes and the quality of the further process steps. We achieve purity values of over 99.99%.

LOW OUTGASSING IN ULTRA-HIGH VACUUM

Even under UHV conditions and at highest temperatures, our CVD products remain stable and safe.

Anisotropic structure

The CVD products derive their structures from crystalline lattice structures and thus display the desired direction-dependent structural properties. This is particularly evident in the case of thermal expansion, since a ratio of approx. 1:10 can be observed here. 

LOW THERMAL MASS

Our CVD products store virtually none of the heat from melting and boiling processes, but give off this heat directly to the environment. 

ELECTRICAL INSULATOR

Pyrolytic boron nitride (PBN) is not electrically conductive and therefore also serves as an insulator in current-carrying components. 

MACHINABLE

If necessary, the CVD products can also be processed further by machine in order to make possible special forms or special applications.  

OUTSTANDING THERMAL SHOCK TOLERANCE

Even with pronounced and rapid changes in the ambient temperature, our CVD products remain unaffected and withstand extreme requirements.

FLEXIBLE

Our CVD products are stable in form yet flexible and can thus be used optimally for different applications. 

TRANSPARENCY TO INFRARED WAVES

The PBN crucibles are easy to penetrate by infrared light. This makes it possible for you to initiate IR processes directly and to carry out the desired process steps without further interruptions.