AVS 54th International Symposium | |
Nanometer-scale Science and Technology | Tuesday Sessions |
Session NS+MS-TuA |
Session: | Characterization of Nanostructures |
Presenter: | N.P. Economou, Carl Zeiss SMT |
Authors: | N.P. Economou, Carl Zeiss SMT B. Ward, Carl Zeiss SMT J. Notte, Carl Zeiss SMT R. Hill, Carl Zeiss SMT L.A. Stern, Carl Zeiss SMT |
Correspondent: | Click to Email |
We have developed the first practical He ion microscope, based on a unique gas field ion source. The source has highly desirable performance characteristics for building scanning ion microscopes with sub-nanometer probe sizes. A unique construction allows the source to provide stable output over useful lifetimes of several hundred hours, thus enabling the development of practical systems for microscopy and nanostructure characterization. An important aspect of the He ion microscope is the interaction of He ions with the sample being observed. As compared with electrons interacting with the same sample, He ions penetrate less deeply, scatter less and produce higher yields of secondary electrons; back-scattered ions are also present. Images produced with a He ion beam exhibit greater material contrast, higher resolution due to reduced interaction volume, and better signal-to-noise ratio. These factors combine to produce He ion images that often contain more and better information than electron images. Because of these inherent advantages, we believe the He ion microscope will become an important tool for the study of nanostructures. We will discuss the unique characteristics of the source, and present images produced from the microscope that demonstrate its advantages over currently available instruments.