Used GATAN 691 #293826925 for sale

GATAN 691 is an ion milling equipment for preparing electron microscopes sample surfaces by removing material in thin layers. The system uses a closed-loop, three-stage electrical/mechanical ion focusing unit to deliver a beam of ions to the sample surface and sputtered material is collected in a double-tube 'burr eliminator'. This enables an accurate control over the ion beam energy parameters — which control the depth of milling — and the angular spread of the beam, which affects the rate of sputtering. The sample platform consists of a 300mm diameter vacuum-sealed platform, which uses a shared feedthrough to power and signal the ion milling source and the sample. The power supply for the accelerated ions is adjustable over a wide dynamic range and during operation the sample is kept at a fixed bias voltage. In addition, the sample platform allows for sample tilting in the x, y, and z-axis using air-driven actuators mounted to the surface of the platform. The source of the beam is a high-power ion gun with a graphing cathode and modified extractor that enable high-performance sputtering. The gun is connected to a series of metal plates which form a Faraday shield, preventing electron contamination of the beam while accelerating the ion beam. In addition, a rare earth magnet is capable of providing an demagnetization field of up to 2 Tesla near the sample surface. The machine also includes an optical video viewing tool, providing a full-field image of the sample surface and enabling an operator to observe milling progress in real time. Finally, for precise control of the milling process, the asset includes a suite of software designed to control the ion beam parameters through the power supply, allowing for control over the beam current, beam energy, spot size, and other parameters. This sophisticated control over the machining process allows for precise milling of samples and ensures precision and reproducible results.