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排序方式: 共有493条查询结果,搜索用时 93 毫秒
1.
研究了不同衬底-阴极距离、直流电压和H2流量对a-CH薄膜沉积速率的影响。结果表明:衬底-阴极距离必须大于0.5cm,随着该距离的增加,薄膜的沉积速率减少;直流电压达550V时沉积速率最大;随着H2含量的增加,CH4含量相对减少,沉积速率随之降低。用AFM观察了以该方法制得的448.4nm CH薄膜的表面形貌,表面粗糙度约为10nm。最后测出了不同条件下CH薄膜的UV-VIS谱,由此可以计算得到薄膜的禁带宽度及折射率。 相似文献
2.
In photochemical vapor deposition of aluminum film on silicon using dimethylaluminum hydride, (CH3)2AlH, a surface reaction dominated below a (CH3)2AlH pressure of 0.3 m Torr at 200°C, which was induced only with the 160 nm band emitted from a deuterium lamp. A gas-phase reaction occurred above 0.3 mTorr at 200°C, which could be induced by both 160 nm and 240 nm emission bands from the lamp. To distinguish between surface ad gas-phase reactions, a thickness profile was used. At 240°C the surface reaction could be induced even by the 240 nm band, while the deposits formed under illumination of the two bands were thinner than those obtained with only the 240 nm band, indicating occurrence of vacuum ultraviolet (VUV)-enhanced desorption. The mechanism responsible for the observed wavelength dependence in unclear. The electrical resistivity of the films deposited at 200°C was 4.5 μΩ cm, which did not change with wavelength. 相似文献
3.
本文证明了d2k =δ2k =d2k ≥b2k,其中d2k ,δ2k , b2k分别表示A(BlMp)在lNq下的Kolmogorov,线性,Bernstein 2k-宽度,d2k 表示AT(BlN相似文献
4.
5.
Takuya Hashimoto Koichi Kitazawa Masaaki Nakabayashi Tadashi Shiraishi Youichi Suemune Takakazu Yamamoto Hideomi Koinuma 《应用有机金属化学》1991,5(4):325-330
For low-temperature deposition of oxide films relating to Bi-Sr-Ca-Cu-O superconductors, photo-absorption and -decomposition properties were examined with respect to copper and alkaline-earth ß-diketonates. It was confirmed that all ß-diketonates examined were promising as source materials for photochemical vapour deposition (photo-CVD) using a low-pressure mercury lamp, in view of their large light absorption coefficients at wavelength 254 nm. The light irradiation was effective for the formation of highly crystalline oxide films at temperatures below 600 °C. By combining two sources, Ca2CuO3 and SrCuO2 films were prepared. Photo-CVD of c-axis oriented Bi2Sr2CuOx film was achieved by the irradiation of ternary sources of Bi(C6H5)3 and strontium and copper ß-diketonates at 500 °C. 相似文献
6.
采用微波电子回旋共振等离子体化学气相沉积(MWPECRCVD)方法,使用不同的源气体(CHF3CH4,CHF3C2H2,CHF3C6H6)体系制备了aC∶F∶H薄膜.由于CH4,C2H2,C6H6气体在等离子体中的分解反应不同导致了薄膜的沉积速率和结构上的差异.红外吸收谱的结果表明,用C6H6CHF3作为源气体沉积的薄膜中几乎不含H,而用C2H2CHF3所沉积的薄膜中的含氟量最高,其相应的CF振动峰位向高频方向偏移.薄膜的真空退火结果表明,aC∶F∶H薄膜的热稳定性除了取决于薄膜的CC键浓度外,还与CC键
关键词:
氟化非晶碳膜
电子回旋共振化学气相沉积
红外吸收光谱 相似文献
7.
Leszek Wachowski Antoni Grodzicki Piotr Piszczek Monika Richert Magdalena Hofman 《Reaction Kinetics and Catalysis Letters》2007,91(1):93-99
Hydrogenation of styrene has been applied as a test reaction to study the catalytic activity of TiO2 deposited by the CVD (chemical vapour deposition) method on the surface of a carbonaceous material enriched in nitrogen (CN). 相似文献
8.
S. Vepřek 《Plasma Chemistry and Plasma Processing》1992,12(3):219-235
Impurity release from the first wall and components facing the hot plasma in Tokamak devices for controlled fusion research and the concomitant pollution of the plasma lead to enhanced energy losses and deuterium-tritium luel dilution. Both these effects can prevent reaching the ignition conditions. The recently developed technique for large areain situ deposition of boron carbide protective coatings by means of plasma-induced chemical vapor deposition enables one to significantly improve the purity of the fusion plasma. The prospects of approaching the scientific break-even in the large machines of the Tokarnak type has been increased.Extended version of an invited paper presented at the 10th International Symposium on Boron, Borides, and Related Compounds, Albuquerque, New Mexico, August 1990.The term Tokarnak is an abbreviation of the Russian name toroidal magnetic chamber. 相似文献
9.
Kolman David Heberlein Joachim Pfender Emil 《Plasma Chemistry and Plasma Processing》1998,18(1):73-89
In this paper, a comprehensive model for thermal plasma chemical vapor deposition (TPCVD) with liquid feedstock injection is documented. The gas flow is assumed to be steady, of a single temperature. Radiation and charged species contributions are excluded, but extensive homogeneous and heterogeneous chemistry is included. The liquid phase is traced by considering individual droplets. Discussion on the model's application to diamond production from acetone in a hydrogen–argon plasma is included. The major conclusions are: (1) Liquid injection possesses a capability to deliver the hydrocarbon precursor directly onto the deposition target. (2) For the case of complete evaporation of the droplet before reaching the substrate, the deposition rate is similar to that obtained with gaseous precursors. (3) The computational results compare well with experimental data. The modeling results can be used to optimize the injection parameters with regard to the deposition rate. 相似文献
10.
《Surface and interface analysis : SIA》2005,37(3):310-315
Carbon film coatings have been produced by a hot‐wall chemical vapor deposition (CVD) method under moderate conditions from pyrolysis of a mixture of propane and argon on an Fe(110) substrate at temperatures of 800–900 °C for different deposition times. The effects of temperature and reaction time on the growth of the carbon films were studied. Field‐emission scanning electron microscopy (FESEM), Raman microscopy, Auger electron spectroscopy (AES) and x‐ray diffraction methods have been performed to study the surface morphologies, growth features and microstructures of the carbon film coatings. The FESEM analyses indicated that carbon films on an Fe substrate consisted of flat‐layer and filamentous morphologies. Raman and AES analyses showed that the carbon initially was crystalline but the degree of disorder in the top layer of the carbon film increased with increasing deposition temperature. High‐resolution transmission electron microscopy studies are also in agreement with Raman results. The same trend was observed when the deposition time was increased from 5 to 30 min. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献