attoPUBLICATIONS attoCATALOG-2015/16 | Page 29

Closed Loop Scanning & Ultra-Large Scan Range ...included with any attoSPM+ Using piezo-based scanners usually relies on the assumption that the relation between applied voltage and displacement is linear. In reality, most scanners show large non-linear behaviour and hysteresis, especially for large scan ranges. Creep, i.e. drift in position after approaching a certain location, is a further phenomenon which is common to all piezo scanners. In some experiments, reproducibly locating a small feature on a surface is crucial, and sometimes hysteresis and non-linearity in the acquired image are not acceptable. This is why the new attoDRY LAB microscopes attoSPM+ are now all equipped with attocube’s unique fiber-based attoFPS interferometer for closed loop functionality with a resolution of 1 nm. 12 5 µ m 125 µm Besides, we managed to further increase the available scan ranges from 50 µm x 50 µm at 300 K and 30 µm x 30 µm at 4 K to a stunning 80 µm x 80 µm at 300 K, and an even larger 125 µm x 125 µm at 4 K. Since this covers an area larger by more than a factor of 16, locating and recovering your region of interest has never been that easy. Naturally, this large range is also covered by our closed loop encoder. 1 Closed Loop1 Interferometric Encoder steady-state resolution (100 ms sample time) 1 nm rms typ. contouring error (10 μm lines) 12 nm @ 1 μm/s scan speed 80 nm @ 10 μm/s scan speed time constant (1 μm step response) 11.7 ms closed loop functionality currently available in combination with a microscope housing and an ASC500 SPM controller attoDRY LAB Dry Measurement Systems attoDRY LAB PAGE 27