Magnetron sputtering has become the process of choice for the deposition of a wide range of industrially important coatings. Examples include hard, wear-resistant coatings, low friction coatings, corrosion resistant coatings, decorative coatings and coatings with speci"c optical, or electrical properties. Although the basic sputtering process has been known and used for many years, it is the de...

Pulsed magnetron oscillators sometimes show an instability known as “twinning” in which the spectrum shows two, or more, closely spaced peaks. This phenomenon is undesirable and can lead to problems when it occurs in magnetrons used in radars. An experimental investigation of twinning is described from which conclusions are drawn about the design parameters that affect it. It has been shown tha...

Zirconium oxide and tantalum oxide films were deposited in an inverted cylindrical magnetron cathode using high power pulsed sputtering. Average power densities were between 5 and 7 W/cm2 and peak power densities were in the range of 0.5 kW/cm2. In all of the experiments the oxygen was introduced using flow control, and the current and voltage waveforms of the HPPMS supply changed in a reproduc...

Nonlinear plasma structures in the partially magnetized E×B of a cylindrical magnetron are investigated using 2D3V particle-in-cell Monte Carlo collision simulations. In early phase discharge, gradients and radial electric fields excite lower hybrid type instability that forms long wavelength rotating density spokes. As discharge grows by ionization cathode gets shielded formation an ion sheath...

To facilitate the construction of the high-power magnetron, the entire output section, including the quarter wave transformer and window, has been redesigned. The new design is based on standard S band waveguide. The quarter wave transformer was changed to increase the external loading of the tube. Cold test measurements on a tube with the redesigned output section give an external Q of 230. Wo...

Recent megawatt gyrotron experiments at MIT have achieved record powers at 170 GHz. Single mode emission with a peak output power of 1.5 MW and an efficiency of 35% has been measured. The experiment is based on a resonant TE28 ,8 ,1 cylindrical cavity situated in a 6.7 T magnetic field. Microwaves are generated in the cavity by an 83 kV annular electron beam produced by a triode-type magnetron ...

A low-power microwave arjet thruster was studied using ammonia gas as propellant. The purpose of the project was to generate ammonia plasma using a 7.5 GHz magnetron and a cylindrical cavity thruster, which is resonant in the TM001 mode [1]. The desired pressure was atmospheric or above while generating a thrust of roughly 20mN and an Isp of about 500s operating at low power (<100 kW). Introduc...

In this work we report on the fabrication process for the development of a flexible piezopolymeric transducer for health monitoring applications, based on lead-free, piezoelectric zinc oxide (ZnO) thin films. All the selected materials are compatible with the space environment and were deposited by the RF magnetron sputtering technique at room temperature, in view of preserving the total flexib...

Sustaining a plasma in a magnetron discharge requires energization of the plasma electrons. In this work, Ohmic heating of electrons outside the cathode sheath is demonstrated to be typically of the same order as sheath energization, and a simple physical explanation is given. We propose a generalized Thornton equation that includes both sheath energization and Ohmic heating of electrons. The s...