As semiconductor device manufacturing gets more and more complex with increased number of steps & smaller critical dimensions of the device, wafer inspection and metrology become more and more critical.
- Dry primary & secondary vacuum
- Low noise & vibration levels
- High performance for high throughput
- Low power consumption for low operating costs
How does it work?
CD SEM are used to perform dimensional measurements in the range of nm scale, as well as material species analysis. In this type of equipment, the electron beam scans the wafer in a raster pattern. But first, electrons are generated at the top of the column by the electron source and then accelerated and attracted by the positively-charged anode. The entire electron column needs to be under vacuum. Like all the components of an electron microscope, the electron source is sealed inside a special chamber in order to preserve vacuum and protect it against contamination, vibrations or noise. Although vacuum protects the electron source from being contaminated, it also allows the user to acquire a high-resolution image. Furthermore, high vacuum increases the collection efficiency of electrons by the detectors that are in the column.
CD SEM operate under low vacuum, typically in the pressure range of 10-5 to 10-7 mbar. Because of the low vibration level required, Magnetically levitated turbopump technology is commonly used. Primary vacuum requires low pumping capacity dry pumps to back the turbopumps.
Our HiPace Plus turbopump line is the best solution for electron microscopes. The vibration level of the HiPace Plus is significantly lower than standard turbopumps. As a primary pump, we can offer various dry solutions: Diaphragm MVP series, Multi-stage Roots pumps ACP Series and our newly developed HiScroll series. We can also provide a wide range of gauges for a total vacuum solution.