PBN / PG Heaters

The PBN/PG ceramic heater combines three layers of ultra-high purity ceramics, PBN-PG-PBN to produce an advanced micro-ceramic heating element system. Both our PBN heater (Pyrolytic Boron Nitride) and PG heater (Pyrolytic Graphite) are manufactured by high temperature CVD. These high performance elements exhibit outstanding thermal properties in a ceramic heater, including high thermal conductivity and anisotropy.

Structure and Manufacturing Process:

The remarkable properties of PBN and PG have been combined by chemical vapor deposition as follows:

	PBN	PG
Process	CVD (High Temperature) (Reduced pressure) BCl3+NH3?BN+3HCl	CVD (High Temperature) (Reduced pressure) CH4+ ?C+2H2
Structure	Boron Nitrogen	Carbon

Properties:

Purity (Total metal impurities)	< 1 ppm	< 1 ppm
Maximum suggested use temperature	3000°C	3600°C

Tensile strength at high temperature ("a" direction):

r.t.	410kg/cm2	1050kg/cm2
2000°C	1030kg/cm2	1400kg/cm2
Chemical inertness	o	o
Thermal shock resistance	o	o
Machinability	o	o
Outgassing	Negligible	Negligible

Resistivity

“a” direction 1000°C	3X107Ωcm	4X10-6Ωcm
“c” direction 1000°C	3X109Ωcm	2X10-3Ωcm

PBN/PG Performance Advantages:

Micro-ceramic heating element has an operating temperature to = 1600°C.
High mechanical durability and dimensional stability.
Dimensionally compact. PBN layer provides electrical insulation.
Thermal gradients can be tailored to meet specific requirements.
Eliminate outgassing and contaminations.
High thermal shock resistance.
Chemically inert to almost all metals, liquids and gas.
Large variety of PG heater and PGN heater shapes available.

Wafer	Rectangle	Rod/Tube	Cup/Boat
Sizes (mm)	Ø380 MAX 1.0~3.0 thickness	260 X260 MAX 1.0~3.0 thickness	260 X260 MAX 1.0~3.0 thickness	Ø300 MAX 200 height MAX