Nitrogenated nanocrystalline diamond films: Thermal and optical properties

作者：Ralchenko V^*; Pimenov S; Konov V; Khomich A; Saveliev A; Popovich A; Vlasov I; Zavedeev E; Bozhko A; Loubnin E; Khmelnitskii R

来源：Diamond and Related Materials, 2007, 16(12): 2067-2073.

DOI：10.1016/j.diamond.2007.05.005

• nanocrystalline diamond films
• grain boundaries
• thermal conductivity
• optical absorption
• annealing

Ultrananocrystalline diamond films have been grown by microwave plasma CVD using CH(4)/H(2)/Ar mixtures with N(2) added in plasma in amounts up to 25%. The films were characterized with AFM, Raman, XRD, and UV-IR optical absorption spectroscopy mainly focusing on optical and thermal properties. In comparison with polycrystalline CVD diamond the UNCD are very smooth (R(a) < 10 nm), have low thermal conductivity (similar to 0.10 W/cm, K), high optical absorption (similar to 10(3) cm(-1) at 500 nm) and high concentration of bonded hydrogen (similar to 9 at.%). The nitrogen presence in the plasma has a profound impact on UNCD structure and properties, particularly leading to a decrease in resistivity (by 12 orders of magnitude), thermal conductivity, Tauc band gap, optical transmission and H content. The UNCD demonstrated rather good thermal stability in vacuum: the diamond phase still was present in the films subjected to annealing to 1400 degrees C.

• 出版日期2007-12