Silicon Nitride is an advanced ceramic material, part of the group called monolithic ceramics and is a highly suitable material for use in Hot Surface Igniters. Silicon Nitride properties are:

	Crystal structure: hexagonal (amorphous for most VLSI applications)
	Atomic Weight 140.28
	Thermal Conductivity 16-33 W/m-K
	Thermal diffusivity .32 cm**2/s
	Relative Dielectric Constant 7.5
	Index of Refraction 2.0
	Dielectric Constant F/m
	Electrical Resistivity > 10e12 ohm-meter
	Breakdown field V/m
	Atomic Density 1.48e22 molecules/cm**3
	Density 3.44 g/cm**3
	Coefficient of Thermal Linear Expansion 2.8e- 6 to 3.6e-6 /K
	Energy Gap 4.7 eV
	Specific Heat .17 J/g-K
	Melting point ~1900 C
	Young's Modulus 304 GPa
	Poisson's Ratio .24
	Koop Hardness 2200
	Modulus of Rupture 414-580 MPa