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In this article, the plasma is created in a Pyrex tube (L = 27 cm, φ = 4 cm) as a single cell, by a capacitive audio frequency (AF) discharge (f = 10-100 kHz), at a definite pressure of ~0.2 Torr. A couple of tube linear and deviating arrangements show plasma characteristic conformity. The applied AF plasma and the injection of electrons into two gas mediums Ar and N2 revealed the increase of electron density at distinct tube regions by one order to attain 10(13)∕cm(3). The electrons temperature and density strengths are in contrast to each other. While their distributions differ along the plasma tube length, they show a decaying sinusoidal shape where their peaks position varies by the gas type. The electrons injection moderates electron temperature and expands their density. The later highest peak holds for the N2 gas, at electrons injection it changes to hold for the Ar. The sinusoidal decaying density behavior generates electric fields depending on the gas used and independent of tube geometry. The effect of the injected electrons performs a responsive impact on electrons density not attributed to the gas discharge. Analytical tools investigate the interaction of the plasma, the discharge current, and the gas used on the electrodes. It points to the emigration of atoms from each one but for greater majority they behave to a preferred direction. Meanwhile, only in the linear regime, small percentage of atoms still moves in reverse direction. Traces of gas atoms revealed on both electrodes due to sheath regions denote lack of their participation in the discharge current. In addition, atoms travel from one electrode to the other by overcoming the sheaths regions occurring transportation of particles agglomeration from one electrode to the other. The electrons injection has contributed to increase the plasma electron density peaks. These electrons populations have raised the generated electrostatic fields assisting the elemental ions emigration to a preferred electrode direction. Regardless of plasma electrodes positions and plasma shape, ions can be departed from one electrode to deposit on the other one. In consequence, as an application the AF plasma type can enhance the metal deposition from one electrode to the other.

Lower ignition voltage (50 up to 200 V) and higher plasma intensity feature the characteristics of the rf driven in vacuum arc ion source. The source is considered self-extracted ion current and could deliver ion currents of ∼10 mA for thin beam (φ∼4 mm) and ∼20 mA for broad beam (φ∼6 cm) at ∼200 V extraction voltage. In this work an investigation is made for the beam diagnostics which include: the beam profiles, beam emittance, energy spread and distribution of the ion species in the ion beam. The increase of the anode voltage affects the decrease of the beam emittance, while the energy spread increases with the decrease of the discharge pressure. The beam emittance is found to be around 200 up to 400 mm mrad. and the energy spread of the ions in the ion beam is around 40 up to 80 eV. The Ar ion specie extracted from the source could reach Ar+5. The beam profiles show that the beam is more convergent with the increase of the accelerating voltage and with the use of proper capacitors between the extraction electrodes.

In the present work, an investigation has been made for the ext raction characteristics and beam diagnosis for a Pierce-type electron gun with spherical anode to acquire an electron beam suitable for different applications. The acceleration voltage increases the electron beam currents up to 250 mA at Accelerat ion voltage 75kV and decreases the beam perveance, beam waist and beam emittance. The min imu m beam radius could be found at the min imu m beam perveance and maximu m convergence angle. Also the increase of the accelerating voltage affects the increase of the beam fluence rate up to 1.3 x 10 18 e/min.cm 2 , due to the increase of the extracted current. Tracing the electron beam profile by X-Y p robe scanner along the beam line at two different places reveals that the spherical anode affects the beam to be convergent. The electron beam could be suited for the two suggested experiments in our lab, p lasma acceleration and surface modifications of poly mers.

A plasma study is performed in order to construct a cell for plasma acceleration purpose. As well, a multicell design is introduced for the injection of beam driver application. The suggested idea is experimentally demonstrated for two plasma cell configuration. The preformed plasma is obtained by a symmetrically driven capacitive audio frequency discharge. It is featured by its moderate pressure of 0.1-0.2 Torr, low consumption power of 130 W maximum, low discharge voltage and frequency up to 950 V and 20 kHz, respectively, and high plasma density from 10(11) to 10(15) cm(-3). The electron temperature obtained by Langmuir double probe varies from 1 up to 16 eV. It is observed that the increases of the discharge voltage and frequency enlarge the plasma parameters to their maximum values. The plasma cell filled with different gases demonstrates that the Ar and He gases manifest the highest ionization efficiency exceeding 100% at 950 V and 20 kHz. The formed plasma is cold; its density is uniform and stable along the positive column for long competitive lifetime. Showing that it follows the conditions to enhance particle acceleration and in conjunction with its periphery devices form a plasma cell that could be extended to serve this purpose. Demonstrating that an injected electron beam into the extended preformed plasma could follow, to long distance, a continuous trajectory of uniform density. Such plasma generated by H(2) or Ar gases is suggested to be used, respectively, for low-density or higher density beam driver.