On-line Scanned Probe Microscopy Transparently Integrated with Dual Beam SEM/FIB Systems

Abstract

A multifunctional scanning probe microscope (SPM) will be described that transparently integrates with a Dual Beam SEM/FIB System. This is done without perturbing any of the capabilities of the Dual Beam in terms of detectors, gas injectors, analyzers etc while allowing for a completely exposed probe tip to be imaged online even with immersion objectives at working distances as short as 4 mm.In addition, the completely free motion of the rotation axis of the stage is maintained with the probe tip at the eucentric point, which makes it possible to orient the sample in any direction on any structure. The X and Y scan range of the atomic force microscopic (AFM) imaging achieves 35 microns with rough motion over 10 millimeters. This permits the SPM to tilt into position perpendicular to the SEM or FIB or under an angle for rapid and accurate placement of the probe tip at or on structures such as biopolymeric materials that are nanometric in X, Y and Z extent. Thus, not only can a structure's nanometric height be accurately profiled but this can be accomplished with the online excellence of SEM for X, Y metrology. Furthermore, electron and ion beam sensitive samples can be imaged and characterized by AFM at high resolution.Of special importance for online focused ion beam (FIB) fabrication is the Z extent of the AFM which is an unprecedented 35 microns. The design also allows placing the probe tip with an orientation facing up for fabrication or facing down for imaging.An additional integral part of the design is electron/ion beam friendly probes with unique characteristics. The functional capabilities of these probes will be described. All such probes are slender, long (>60 microns) with an axial ratio that can be as high as 10:1. All such probes designed for this combination of SPM with SEM/FIB have highly exposed probe tips. This, combined with the Z extent of the AFM imaging provides deep trench capabilities especially important for FIB fabrication. The system allows for standard imaging modalities such as elasticity and data on the relative elasticity of copper on silicon is shown below and will be presented.Within the class of probes that have been implemented with SEM are probes for nanometric optical nearfield imaging (NSOM) and data on GaN wires excited by electron beams will be shown as part of this presentation. Other functionalities existing for such probes exist such as thermal, magnetic and electrical.Such a combination of SPM with the Dual Beam capabilities of SEM/FIB is in effect a new form of analytical instrument which portends to be a disruptive technology affecting the potential of 640

Integrating electron and near-field optics: dual vision for the nanoworld

“…A prototype demonstration system was described at the 2012 Microscopy and Microanalysis meeting [55]. The scanning probe microscope was integrated with a Dual Beam SEM/FIB system that allowed for imaging of the exposed probe tip with immersion objectives at a working distance as low as 4 mm.…”