This article describes an atomic force microscope (AFM) that can operate in any scanning electron microscope (SEM) or SEM combined with a focused ion-beam (FIB) column. The combination of AFM, SEM imaging, energy-dispersive X-ray spectrometry (EDX), FIB milling, and nanofabrication methods (field-emission scanning probe lithography, tip-based electron beam induced deposition, and nanomachining) provides a new tool for correlative nanofabrication and microscopy. Piezoresistive, thermo-mechanically actuated cantilevers (active cantilevers) are used for fast imaging and nanofabrication. Thus, the AFM with active cantilevers integrated into an SEM (AFMinSEM) can generate and characterize nanostructures in situ without breaking vacuum or contaminating the sample.

An in situ electron energy loss spectroscopy (EELS) technique has been developed to investigate the dynamic processes associated with electron-beam nanofabrication on thin membranes. In this article, practical applications germane to e-beam nanofabrication are illustrated with a case study of the drilling of nanometer-sized pores in silicon nitride membranes. This technique involves successive acquisitions of the plasmon-loss and the core-level ionization-loss spectra in real time, both of which provide the information regarding the hole-drilling kinetics, including two respective rates for total mass loss, individual nitrogen and silicon element depletion, and the change of the atomic bonding environment. In addition, the in situ EELS also provides an alternative method for endpoint detection with a potentially higher time resolution than by imaging. On the basis of the time evolution of in situ EELS spectra, a qualitative working model combining knock-on sputtering, irradiation-induced mass transport, and phase separation can be proposed.

A new TEM sample preparation technique using electron-beam-induced deposition combined with low-energy ion milling was used to fabricate for two different shapes of sample, conical and plate. High-quality HREM images can be obtained from samples prepared by this technique. A desired sample position can be obtained with high accuracy, and the total sample preparation time can be much less than conventional techniques. Because the gas deposition system used can easily be integrated in a conventional SEM, the method can be performed in any laboratory equipped with a SEM and an ion milling machine.

In this article, we report a technique for growing carbon nanotubes in a more controllable fashion, which enables us to synthesize nanotubes directly in various forms of designed patterns. This nanofabrication process is based on a combination of focused ion beam (FIB) and chemical vapor deposition (CVD) techniques. In this process, arrays of conductive patterns were first deposited on silicon substrates by directing a gaseous compound (C9H16Pt) via the capillary needle-sized nozzles within a FIB system. The substrates were then coated with catalyst and further modified by the FIB to localize the position of the catalyst. Finally, the growth of carbon nanotubes on the designed substrates was carried out by CVD of hydrocarbon gases. This fabrication technique has the advantage of positioning carbon nanotubes in selected locations. This may open up opportunities for the direct synthesis of carbon nanotubes onto almost any substrate material, thus allowing fabrication of carbon nanotube-based devices.

In this paper, we review the approaches developed in our laboratory for polymer-based micro/nanofabrication. For fabrication of microscale features, UV-LIGA (UV-lithography, electroplating, and molding) technology was applied for low-cost mass production. For fabrication of sub-micron or nanoscale features, a novel nano-manufacturing protocol is being developed. The protocol applies a novel nano-lithography imprinting process on an ultra-precision motion-control station. It is capable of economically producing well-defined pores or channels at the nanometer scale on thin polymer layers. The formed thin layers can be used as nano-filters for chemical or bio-separation. They can also be integrated into miniaturized devices for cell immunoprotection or tissue growth. For bonding of polymer-based microfluidic platforms, a novel resin-gas injection-assisted technique has been developed that achieves both bonding and surface modification. This new approach can easily seal microfluidic devices with micron and sub-micron sized channels without blocking the flow path. It can also be used to modify the channel shape, size, and surface characteristics (e.g., hydrophilicity, degree of protein adsorption). By applying the masking technique, local modification of the channel surface can be achieved through cascade resin-gas injection.