The new SU8000 is ideally suited to imaging of new and innovative nanotechnology materials and features a triple detection system along with a semi-in-lens type of objective lens to maximize surface and sub-surface information provided by the secondary and backscattered electron signals.
A new top detector is a further advance on the popular upper backscattered electron detector used in the S-5500. By combining the top detector with the proven upper detector with ExB filter technology, Hitachi has now developed a new signal detection system for optimum contrast visualization of signals, generated from the sample especially under low-accelerating voltage conditions best suited for observation of nanomaterials. These signals include secondary electrons, low-angle backscattered electrons and high-angle backscattered electrons, which are acquired for observation of surface structures.
The Hitachi SU8000 includes an Upper detector, which provides highly efficient SE signal detection employing Hitachi’s proprietary and popular ExB filter technology. This capability provides high-resolution top surface structure imaging, while charging is controlled by varying the ratio of secondary and backscattered electron signal collection.
The upper image example on the right shows the surface of a blue-ray DVD, recorded at 1kV accelerating voltage with the upper detector of the SU8000. The pure SE signal represents exclusively top surface topographical information.
The new Top detector can detect high-angle backscattered electrons at low accelerating voltages. This imaging component represents pure channeling and compositional contrast of the sample without surface-topographical artifacts. This is shown in the lower image on the right, showing the same blue-ray DVD position but now imaged with the Top detector.
With Hitachi’s beam deceleration technology and the use of the top detector, high-resolution observations can be performed at ultra-low landing voltages. The top detector now captures the accelerated secondary electrons with energies less than 10eV (left picture in example below) transporting surface potential information, while the upper detector receives low-angle backscattered electrons (right picture below) bearing topographical information. This new combination allows surface information never seen before to be visualized at accelerating voltages as low as 100V.
The SU8000 detection system can be optionally further expanded by an annular semiconductor-type BSE detector, mounted below the SEM objective lens. This penta-device detector (PD-BSE detector) features 4+1 independent segments, allowing flexible comination and subtraction of each segment's signal for optimized visualization of angle-dependent backscattered electron information, e.g. from nanocrystaline samples.
In addition, SU8000 is equipped with a chamber Everhard-Thornley SE detector, and can optionally also observe transmitted electron signals (DF and BF STEM imaging).
The schematic overview, and the table below, give a comprehensive overview over the entire detector range available on the HITACHI SU8000, and the signal type observable by each of them.
