The Diagnose Of Self-Plasma In Radio-Frequency Glow Discharge During Electron Beam Evaporation

In order to overcome the shortcomings of electron beam evaporation technique and improve the adhesion strength between the film and substrate, thereby increasing the electron beam evaporation technology applications. In this paper, a self-design coil was added to the original laboratory equipment. In the experiment, first, the radio-frequency power with driving frequency of 13.56MHz was accessed to the cylindrical coil. Metal vapor is ionized to plasma by the RF glow discharge between the coil and the crucible. In the vacuum chamber, the very strong blue light was observed after the application of RF power; Second, the effect of the geometric configuration of the coil, the discharge parameters to the reflected power were studied, results showed that the diameter of 82mm RF coil with 3-turn and the discharge distance of 100mm were more appropriate parameters which have the minimum reflected power. Other than the fluency of electron beam were above 160mA, the discharge was easier to happen, but when the electron beam is greater than 200mA, the film would be to fall off; Finally the plasma parameters has been studied by probe and emission spectroscopy .From the experiment measurements of probe, it can be found that the increase of RF power caused the enhancement of ion density at various locations in the vacuum chamber, especially coil center. When RF power is 170W, the ion density of each location increased dramatically. This may be related to the transitions in discharge mode. The increase of the fluency of electron beam also lead to improve ion density, but in the radius of 4cm-7cm at the radial ion density increased considerably. As the axial distance increases, the plasma in the same plane tends to uniform.By plasma emission spectroscopy, the characteristics of the plasma spectrum are the superposition of a continuous series of characteristic spectral lines, which focused on the characteristic spectrum between 300nm to 700nm. After calibration and found that most of the particles are excited states of titanium atoms, and only a small amount of a price of titanium ions, a more expensive state of the titanium ions was not found. As RF power increased, the number of spectral and the intensity of spectral were greatly improved. The relative intensity of ionic lines and some atomic lines (such as the 453.8nm atomic line) increases with the power increased, while the other atom line intensity is increased with little change. As the axial distance rose, the intensity of each line has a decreasing trend. This is the ion density measured with the probe results coincided, but also from other verification of the probe measurements. The excitation temperature of plasma was measured by Boltzmann plot. The excitation temperature variation with RF power in different axial was studied. The result show that with the increase of RF power, excitation temperature gradually increased. Owe to electron density and FWHF have a linear realationship.we used FWHF representation electron density. Electron density gradually increases with increasing RF power, where the RF power is 170W, the electron density increased dramatically.