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We demonstrate a method for charge recombination imaging in the scanning electron microscope and employ this technique to directly image the two-dimensional projection of the generation volume as a function of electron energy and probe current. Using GaAs and SiC bulk samples, we observe the lateral extent of the generation volume increasing as a function of increasing e-beam accelerating voltage, in excellent agreement with previous work. This work also reveals significant variations in minority carrier distribution within the volume for low-Z compared to the high-Z material. The roles of sample geometry and carrier diffusion are discussed. The direct imaging technique used in this work is well suited for further studies of the nature of the effective interaction region for cathodoluminescence or electron-beam induced current studies in any luminescent material. [ABSTRACT FROM AUTHOR]

Electron-beam-induced deposition (EBID) is a versatile micro- and nanofabrication technique based on electron-induced dissociation of metal-carrying gas molecules adsorbed on a target. EBID has the advantage of direct deposition of three-dimensional structures on almost any target geometry. This technique has occasionally been used in focused electron-beam instruments, such as scanning electron microscopes, scanning transmission electron microscopes (STEM), or lithography machines. Experiments showed that the EBID spatial resolution, defined as the lateral size of a singular deposited dot or line, always exceeds the diameter of the electron beam. Until recently, no one has been able to fabricate EBID features smaller than 15–20 nm diameter, even if a 2-nm-diam electron-beam writer was used. Because of this, the prediction of EBID resolution is an intriguing problem. In this article, a procedure to theoretically estimate the EBID resolution for a given energetic electron beam, target, and gaseous precursor is described. This procedure offers the most complete approach to the EBID spatial resolution problem. An EBID model was developed based on electron interactions with the solid target and with the gaseous precursor. The spatial resolution of EBID can be influenced by many factors, of which two are quantified: the secondary electrons, suspected by almost all authors working in this field, and the delocalization of inelastic electron scattering, a poorly known effect. The results confirm the major influence played by the secondary electrons on the EBID resolution and show that the role of the delocalization of inelastic electron scattering is negligible. The model predicts that a 0.2-nm electron beam can deposit structures with minimum sizes between 0.2 and 2 nm, instead of the formerly assumed limit of 15–20 nm. The modeling results are compared with recent experimental results in which 1-nm W dots from a W(CO)6 precursor were written in a 200-kV STEM on a 30-nm SiN membrane. [ABSTRACT FROM AUTHOR]

Standard samples with programed defects, designed to evaluate pattern inspection tools that use electron beams, were fabricated on 12-in. Si wafer. By using a structure with a conductive pattern on an insulator layer, scanning electron microscope (SEM) images with various pattern contrasts, depending on the charging effect, were obtained under different observation conditions. The impact of captured-image contrast on defect detection capability was examined using different types of inspection algorithm. It was found that the accuracy of critical dimension measurement, effectiveness of the charge suppression technique, and defect detection capability of the SEM tool, and its robustness could all be evaluated using this standard sample with a particular stacked structure. [ABSTRACT FROM AUTHOR]