Boron-rich boron nitride (BN) films have been prepared on Si and SiO2/Si su
bstrates by the vacuum pyrolysis of spin-coated polyborazine films. physica
l properties of the prepared films such as film strength, thermal conductiv
ity, and dielectrics were determined. The BN films vacuum-pyrolyzed at 900
degreesC showed residual N-H bonds with a 0.75 N/B ratio, interdiffusion ph
enomena, and preferred orientation at the interfacial zone. Hardness and th
e elastic modulus of the film increased to 1.6 GPa and 50 GPa by nanoindent
ation loading. It had a thermal conductivity of 134 W/(m.K) at 296.5 K, and
a dielectric constant in the range of 5-7, with tan partial derivative bet
ween 0.01 and 0.47, depending on the film thickness.