Ti-Si-N composite coatings were synthesized on a novel combining cathode and middle-frequency magnetron sputtering system, designed on an industrial scale. Ti was produced from the arc target and Si from magnetron target during deposition. The influences of negative bias voltage and Si content on the hardness and microstructure of the coatings were investigated. The composite coatings prepared under optimized conditions were characterized to be nc-TiN/a-Si3N4 structure with grain sizes of TiN ranging from 8-15 nm and exhibited a high hardness of 40 GPa. The enhancement of the hardness is suggested to be caused by the nanograin-amorphous structure effects.
Thick CrN coatings were deposited on Si(111)substrates by electron source assistedmid-frequency magnetron sputtering working at 40 kHz.The deposition rate,structure.andmicrohardness of the coatings were strongly influenced by the negative bias voltage(V_b).Thedeposition rate reached 8.96 μm/h at a V_b of-150 V.X-ray diffraction measurement revealedstrong CrN(200)orientation for films prepared at low bias voltages.At a high bias voltage of V_bless than-25 V both CrN(200)and(111)were observed.Large and homogeneous grains wereobserved by both atomic force microscopy and scanning electron microscopy in samples preparedunder optimal conditions.The samples exhibited a fibrous microstructure for a low bias voltageand a columnar structure for V_b less than-150 V.
