To improve the pyrolytic carbon (PyC) deposition rate of Carbon/Carbon (C/C) composites prepared by the traditional chemical vapor infiltration (CVI) method, the 3D Ni/wood-carbon (3D Ni/C) catalyst was introduced into the CVI process. The effects of catalyst on the density of C/C composites were studied, and the deposition rate and morphologies of PyC were investigated after catalytic CVI. The morphologies of catalyst and PyC were characterized by scanning electron microscope and polarized light microscopy. The catalytic deposition mechanism of PyC was studied by density functional theory. The experimental results show that the initial carbon deposition efficiency of the catalytic pyrolysis process was 3–4 times that of the noncatalytic process. The catalyst reduced the energy barrier in the first step of deposition reaction from 382.55 to 171.67 kJ/mol according to simulation results. The pyrolysis reaction energy with Ni catalyst is reduced by 54% than that without the catalyst.

We investigated a Leidenfrost effect in the growth of ZnO nanostructures on silicon substrates by ultrasonic-assisted spray pyrolysis deposition(SPD). Structural and optical properties of the ZnO nanostructures grown by varying the growth parameters, such as substrate temperature, source concentration, and suction rate of the mist in the chambers, were investigated using field-emission scanning electron microscopy, X-ray diffraction, and photoluminescence spectrum analysis. Structural investigations of the ZnO nanostructures showed abnormal evolution of the morphologies with variation of the substrate temperatures. The shape of the ZnO nanostructures transformed from nanoplate, nanorod, nanopencil, and nanoprism shapes with increasing of the substrate temperature from 250 to 450 °C; these shapes were significantly different from those seen for the conventional growth mechanisms in SPD. The observed growth behavior showed that a Leidenfrost effect dominantly affected the growth mechanism of the ZnO nanostructures.

Ti[N (C2H5 CH3)2]4 [tetrakis(ethylmethylammino)titanium.TEMAT]와 NH3를 반응가스로 하여 각각 펄스(pulse) 형태로 시분할 주입되는 새로운 박막 증착방법(이하 Cycle-CVD라 함)을 이용하여 TiN박막이 SiO2.기판위에 증착되었다.Cycle-CVD에서 반을로 내로 주입되는 반응가스와 Ar가스는 TEAM 펄스, Ar 펄스,NH3펄스, Ar 펄스의 순서로 시분할주입되었고, 이렇게 차례대로 주입되는 4개의 펄스를 하나의 cycle로 규정하고, Cycle-CVD는 이러한 cycle이 연속하여 반복적으로 주입되도록 설계되었다. 기판온도가 170˚C-210˚C에서는 atomic layer deposition(ALD)특성을 보였고, 200˚C에서 충분한 반응가스의 펄스시간 후에 cycle당 증착된 박막의 두께가 0.6nm/cycle로 포화되는 양상을 보여주었는데, 이는 cycle당 증착된 TiN 박막의 두께가 1.6 monolayer(ML)/cycle에 해당된다. 이와 같이 반등가스의 흡착을 이용ㅇ하여 TiN이 제한된 표면반응만에 의하여 ALD 기구에 의해 증착이 이루어지므로 TiN 박막의 두께는 단지 cycle 횟수만으로 정확하게 제어할 수 있었고, 우수한 step coverage 특성을 얻었다. 또한 반응가스간의 기상반응을 방지함으로써 입자의 발생을 억제할 수 있었고, 상대적으로 낮은 온도임에도 불구하고 4at% 이하의 낮은 탄소함량을 갖는 양호한 특성을 보여주었다.