Nano-scale fabrication

Traditional methods for fabricating nano-scaled arrays are usually based on lithographic techniques. Alternative new approaches rely on the use of self-organizing templates. Due to their intrinsic ability to adopt complex and flexible conformations, proteins have been used to control the size and shape, and also to form ordered two-dimensional arrays of nanopartides. The following examples focus on the use of helical protein templates, such as gelatin and collagen, and protein cages such as ferritin-based molecules. 

Oh, B. K., Lee, W., Lee, W. H., and Choi, J. W. (2003). Nano-scale probe fabrication using self-assembly technique and application to detection of Escherichia coli 0157 H7. Biotechnol. Bioprocess Eng. 8, 227-232. 

Confined quantum systems of a finite number of electrons bound in a fabricated nano-scale potential, typically of the order of 1 100 nm, are... 

Colored water drops are shown beading on Kevlar fabric treated with a nano-scale water-resistant coating. 

Nano-scale polymer patterning was reported to be fabricated by the enzymatic oxidative polymerization of caffeic acid on 4-aminothiolphenol-functionalized gold surface with dip-pen nanolithography technique [74],... 

The porous SiC is fabricated from commercial SiC substrate (4H or 6H) by electrochemical etching. An electrolyte is placed in contact with the SiC substrate. A bias is introduced across the electrolyte and the semiconductor materials causing a current to flow between the electrolyte and the semiconductor material. The SiC partially decomposes in this electrolyte and forms high density of pores with nano-scale diameter. This decomposition initiates from the carbon-face of SiC substrate because the carbon-face is less chemically inert compared with the silicon-face. These as-etched pores have a depth of approximately 200 pm but do not reach the silicon-face of SiC. To fabricate porous silicon-face SiC (silicon-face is used as the growth plane for GaN), SiC with thickness of tens of micrometers is polished away from the silicon-face to expose the surface pores. Two surface preparation procedures, hydrogen polishing and chemical mechanical polishing, have been applied to the as-polished silicon-face porous SiC to improve its surface perfection. 

Polymer materials find a wide application in replication technologies for producing structures with submicron elements of intricate shapes and for nano-scale surface replication [1-4]. They show considerable promise for smoothing out the surface roughness to obtain good-quality inexpensive substrates used in fabrication of X-ray optic components [5,6], In this work, the features of silicon wafer surface replication by polymers were studied by atomic-force microscopy (AFM) and X-ray reflectometry (XRR) with a view to applying this replication technique to produce smooth polymer-glass combination substrates to be used in multilayer X-ray mirrors. 

Tao, F. F., Guan, M. Y, Zhou, Y. M., Zhang, L., Xu, Z., and Chen, J. (2008). Fabrication of nickel hydroxide microtubes with micro- and nano-scale composite structure and improving electrochemical performance, Cryst Growth Des., 8, pp. 2157-2162. 

Such devices also have higher current drive and are easier to fabricate than devices based on a single SWNT. A well established method of fabricating micro and nano-scaled devices is the process known as photolithography. This manuscript will present a brief background and description of how this fabrication method is provided entailing how nano-scaled device fabrication can be achieved using already in place and well understood techniques. 

We have also reported several examples of fabricating nano-scale features. 

Altering the relationship of the surface area of the fabric to contact with contamination, through working on a nano-scale may shift these levels of speed, sensitivity and selectivity. 

Block copolymers. The multi-component systems are intramolecular, with each component occupying a certain length of chain sequences, as shown in Fig. 2.8a. They can be diblock, triblock or even multi-block copolymers. Upon the change of composition, the microphase separation in block copolymers can fabricate various geometries of regularly packed microdomain patterns with nano-scale resolution, as will be introduced in Sect. 9.3. 

Diblock copolymers can form only molecular-scale small domains of microphase separation rather than macroscopic phase separation, because of the constraint of the covalent bond between the two components. According to compositions, the major compruient forms the continuous matrix, while the minor component forms the microphase domains. The most conunMi equilibrium geometric shapes of microdomains can be lamellae, gyroids, cylinders and spheres, as illustrated in Fig. 9.11, which pack orderly into a nano-scale periodic pattern and be used as nano-scale templates for the fabrication of functional nano-materials (Bates and FredticksOTi 1990 1999). 

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