Pyrolytic Boron Nitride, abbreviated as Pyrolytic BN or PBN, also known as Chemical vapour-deposited Boron Nitride, Chemical Vapour-deposition of Boron Nitride or CVD-BN, etc. As the name suggests, this is a kind of boron nitride prepared by high temperature pyrolysis reaction by chemical vapor deposition method.
Pyrolytic Boron Nitride (PBN) material has high purity, chemical inertness and excellent structure and performance, making it an ideal container for element purification, compound and compound semiconductor crystal growth, especially for the preparation of a new generation of compound semiconductor GaAs, InP, etc. It is also widely used in aviation, aerospace, electronics, chemical industry, special metallurgy, medical and other fields. The main uses of PBN are as follows:
(1) Container for compound semiconductor single crystal growth
The growth of compound semiconductor single crystals (such as GaAs, InP, etc.) requires extremely strict environments, including temperature, raw material purity, and growth container purity. PBN is the most ideal container for compound semiconductor single crystal growth at present, and it is irreplaceable. Compound semiconductor single crystal growth methods currently mainly include liquid-sealed Czochralski (LEC), horizontal Breman method (HB) and vertical Breman method (VB and VGF). The corresponding PBNs include LEC crucible, VB crucible and VGF crucible and so on;
(2) Beam source crucible for molecular beam epitaxy
Molecular beam epitaxy (MBE) is one of the most important epitaxial growth processes for group III-V and group II-VI semiconductor crystals in the world today. PBN crucible is the best container for evaporating elements and compounds in the MBE process;
(3) Crucible for OLED
OLED must be familiar to everyone, and it has been very hot recently. It is said that iPhone 8 will start to adopt OLED screen. The crucible for OLED is used as an evaporation element container on the OLED production line.
(4) PBN ring and sheet
PBN can be heated to 2300°C under ultra-high vacuum without decomposition. It has high purity, reaching more than 99.99%, and does not release gas impurities at high temperatures. These characteristics enable PBN to be processed into different shapes. Rings and sheets, which are widely used in high temperature, vacuum, MBE and OLED fields, as support frames, insulating parts and gaskets.
(5) PBN coating
In liquid phase epitaxy and MOCVD, PBN is often used to coat the graphite parts in the equipment, and can also be used as the outer coating of the graphite heater (PG/PBN heater) to prevent the volatilization of the graphite heater at high temperatures. In addition, because the PBN film has extremely high chemical inertness, it can be used as a diaphragm or passivation film in the semiconductor etching process;
