A novel probe for the measurement of forces exerted by a beam of ions and neutral atoms on a small target is described. The force probe is intended for various applications: First, diagnostics of thruster plumes of electric spacecraft propulsion engines, in particular the determination of the spatial distribution of the momentum in an exhaust beam, and second, the study of sputtering of solid targets by means of the related momentum transfer. The instrument makes use of a sensitive cantilever whose elastic deflection is measured interferometrically along two axes and enables that way a simultaneous measurement of two independent components of the force vector. The present contribution focuses on setup and calibration of the probe. Example measurements with obliquely irradiating ion beams are performed.

Broad beam ion sources are an important tool for industrial surface treatments. They are used for ion beam etching, sputter deposition, structuring and ion implantation [1]. In such sources,

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The article reports on non-electrostatic diagnostics for ion beams. A novel galvanometric force measuring probe is presented, and results are compared with corresponding measurements by a calorimetric technique and using falling microparticles. The target chamber is operated at argon pressures where charge-exchange collisions are important. It is highlighted that non-electrostatic methods are sensitive for ions as well as energetic neutral atoms. For the first time, bombardment induced light emission (BLE) from solid targets is proposed as simple beam diagnostic.

The article presents a device for spatially resolved and simultaneous measurements of forces and currents in particle beams, especially in beams composed of ions and neutral atoms. The forces are exerted by the impinging beam particles on a plane circular conductive target plate of 20 mm diameter mounted on a pendulum with electromagnetic force compensation. The force measurement in the micronewton range is achieved by electromagnetic compensation by means of static Helmholtz coils and permanent magnets attached to the pendulum. Exemplary measurements are performed in the 1.2 keV beam of a broad beam ion source. The simultaneous measurements of forces and currents onto the same target are compared with each other and with Faraday cup measurements.