The most special features of this scanning electron microscopy are that it is truly a tabletop SEM, it is portable and it is designed for minimal preparation of specimens. The microscope is lightweight by design, using a diaphragm pump instead of a rotary pump and a turbomolecular pump instead of a diffusion pump to achieve a useful vacuum for observation. Also the vacuum is on the low side, so it is a semi-environmental SEM and quite tolerant of moisture (unlike any of our other electron microscopes!). The SEM functions by a touch screen and features automated astigmation, focusing, start up and alignment.
The HITACHI TM3000 is used for normal sized specimens. There is no airlock. Specimens are mounted on a specialized holder adjusted in height to optimize operation and the SEM is then pumped down until the green progress bar indicates that the microscope is ready. A serious use for this instrument is screening plant and insect mutants in genetic studies where rapidity of specimen exchange is needed and high resolution is not. Minimal specimen preparation is required because the imaging mode used is tolerant of moisture and charging.
HITACHI TM3000 SEM Characteristics
- Accelerating voltage: 5 or 15 kV, tungsten source
- Magnification: X 15 to X 30,000
- 30 nm resolution
- Backscattered detector only
- Charge reduction mode (which uses higher chamber pressure) allows imaging of uncoated samples
- Easy to use and portable