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Product Briefing Outline: Carl Zeiss SMT has officially launched the ‘ORION' Helium ion microscope based on proprietary intellectual property developed by ALIS Corporation, a Peabody, Massachusetts-based start-up company acquired by Carl Zeiss SMT in 2006. According to Carl Zeiss SMT, this new microscope is capable of providing images of unrivalled high resolution, surface information and material contrast, unachievable with any other microscopy instrument available today.

Problem: Being able to see to the atomic level is critical. Scanning Electron Microscopes typically have excellent resolution, but not particularly good material contrast. Without good material contrast, it can be difficult to determine where the edge of a critical feature is. The Orion helium ion microscope offers a significant advantage over traditional SEM technology. SEM's typically produce one secondary electron for each incoming electron. The helium ion beam, by contrast, produces from 3-9 secondary electrons, depending on the substrate material, for each incoming helium ion. This creates a better signal with higher contrast between different materials. In the field of defect review the standard for material identification today is energy dispersive X-ray analysis. This technique suffers from a lack of resolution as the volume being analyzed can often be much larger than the defect itself. The Orion helium ion microscope can collect and analyze backscattered helium ions, much like in Rutherford Backscattered Spectroscopy, and determine the different materials in the sample with submicron resolution.

Solution: The ORION scanning ion microscope uses a beam of Helium ions —rather than electrons typically used in scanning electron microscopes (SEM) — to image and measure. Since Helium ions can be focused into a substantially smaller probe size and provide a much smaller sample interaction compared to electrons, the ORION system can generate higher resolution images with greatly improved material contrast at a substantially extended depth of focus. Because the ORION ion beam appears to be emanating from a region which is less than an angstrom in size, the resulting ion beam has a remarkable brightness. This makes it possible to focus the beam into a very small probe size.

Applications: Failure analysis, CD control and defect review.

Platform: The Orion helium ion microscope operates somewhat like a typical focused ion beam system. There is a source, which produces a stream of helium ions; a column which accelerates, collimates, focuses and scans the beam; and a vacuum chamber that contains the sample to be imaged. A variety of detectors provide the flexibility of generating images.

Availability: July 2007 onwards.