Control of Deposition Process of Metal Vapor by Themal Energy

The mechanisms of vacuum deposition of metal vapors are investigated experimentally to controlcrystalline structures of thin films by thermal energy methods such as infrared laser irradiation因此on.Knudsen cell was used as a metal evaporation source. The subs The holder was equippedfacing to the Knudsen cell. the distance the between holder and the crucible was about 300 mm andthe angle between them about 13.5 degree. the temperature of the substrate mounted on the holdercould be controlled with a K-type thermocouple and a sheath heater and/or liquid n_2 . In thisexperiment, Al， Mn and Ag被用作evaporant metals and (100) Si wafer，glass and (100) NaCl单加密as substrates. Deposited thin films were analyzed with RHEED，SEM和EPMA. The obtained results are as follows；(1) substrate temperature plays an important role on The crystalline of a thin film. In case ofsubstrate temperature of 196c，amorphous thin films obtained and in case of higher substrate temperature，policrystalline thin films were obtained. The average grain size of thin films becomes large withthe substrate temperature. This result implies the possibility of the control of the positionmechanism and crystalline structures of thin films by thermal energy methods.(2) It not beobserved the effect of the local excitation of the intramolecular vibrations of metal atoms by YAGlaser irradiation on the thin films.(3) the infrared spectra of metal thin films of about 100athickness were almost the same as those of bulk metals.(4) promotion of the metal vapordeposition by electron beam irradiation was observed but the marked change in the crystalline(5)电子领域的影响(influence of electric field on Thegrowth of thin metal films on (100) NaCl substrate not observed. The reason is guessed that as我们使用Knuden cell as evaporant source in these experiments，there are few ions in the metal vapor。

The mechanisms of vacuum deposition of metal vapors are investigated experimentally to control crystalline structures of thin films by thermal energy methods such as infrared laser irradiation and so on.Knudsen cell was used as a metal evaporation source. The subs the holder was equipped facing to the Knudsen cell. The distance the between holder and the crucible was about 300 mm and the angle between them was about 13.5 degree. The temperature of the substrate mounted on the holder could be controlled with a K-type thermocouple and a sheath heater and/or liquid N_2. In this experiment, Al, Mn and Ag were used as evaporant metals and (100) Si wafer, glass and (100) NaCl single crystal as substrates. Deposited thin films were analyzed with RHEED, SEM and EPMA. The obtained results are as follows ;(1) The substrate temperature plays an important role on the crystalline of a thin film. In case of the substrate temperature of ー196 C, amorphous thin films were obtained and in case of higher substrate temperature, policrystalline thin films were obtained. The average grain size of thin films becomes large with the substrate temperature. This result implies the possibility of the control of the deposition mechanism and crystalline structures of thin films by thermal energy methods.(2) It could not be observed the effect of the local excitation of the intramolecular vibrations of metal atoms by YAG laser irradiation on the thin films.(3) The infrared spectra of metal thin films of about 100A thickness were almost the same as those of bulk metals.(4) The promotion of the metal vapor deposition by electron beam irradiation was observed but the marked change in the crystalline structure by this electron irradiation was not observed.(5) The influence of electric field on the growth of thin metal films on (100) NaCl substrate was not observed. The reason is guessed that as we use the Knuden cell as evaporant source in these experiments, there are few ions in the metal vapor.