Growth at these conditions during 5 minutes resulted in ZrB2 film thicknesses between 250 and 300 nm. A more detailed description of the sputtering conditions can be found in . Pole figure measurements showed an epitaxial relationship of ZrB2(0001)║4H-SiC(0001) and ZrB2[11 ̅ 00]║4H-SiC [11 ̅ 00] between the film and substrate, i.e. the ZrB2 films were free of twinning. The boron nitride films were deposited on the templates from the reactants TEB and NH3 in a hot-wall horizontal CVD reactor with a base pressure below Pa at a temperature of 1485 °C and a pressure of 7000 Pa, using a growth time of 120 minutes. The process was performed by reacting 0.7 sccm TEB (99.99% purity, SAFC HiTech) diluted in 170 sccm H2 and 450 sccm NH3,(99.999% purity) in 5000 sccm hydrogen (H2, 99.9996% purity, further purified by a palladium-membrane) and with 0.026 sccm silane (SiH4, 99.999% purity, 2000 ppm diluted in 99.9996%-purity H2 ). The TEB was diluted a separate quartz liner to avoid the possibility of the formation of an NH3:B(CH2CH5)3 adduct prior to reaching the hot zone. The process pressure was regulated by a throttle valve and the deposition temperature was monitored by a pyrometer (Heitronics KT81R, calibrated by silicon melting).