Nanolithography templates

Fig. 8 Schematic representation of block copolymer nanolithography process, a Schematic cross-sectional view of a nanolithography template consisting of a uniform mono-layer of PB spherical microdomains on silicon nitride. PB wets the air and substrate interfaces, b Schematic of the processing flow when an ozonated copolymer film is used as a positive resist, which produces holes in silicon nitride, c Schematic of the processing flow when an osmium-stained copolymer film is used as a negative resist, which produces dots in silicon nitride, (taken from [44])...

The most important nanomaterial synthesis methods include nanolithography techniques, template-directed syntheses, vapor-phase methods, vapor-liquid-solid (VLS) methods, solution-liquid-solid (SLS) approaches, sol-gel processes, micelle, vapor deposition, solvothermal methods, and pyrolysis methods [1, 2]. For many of these procedures, the control of size and shape, the flexibility in the materials that can be synthesized, and the potential for scaling up, are the main limitations. In general, the understanding of the growth mechanism of any as-... 

Particularly in 2D systems, control over the self-assembly of colloidal templates has offered a versatile way to produce patterned surfaces or arrays with a precision of few nanometres. Diblock copolymer micellar nanolithography (dBCML) is a versatile method that uses homopolymers or block copolymers for the production of complex surface structures with nanosized features [69], In contrast to other approaches like electron-beam lithography (EBL) and photolithography, dBCML does not require extensive equipment. In fact, it is commonly used in the fabrication of data storage devices and photonic crystals, in catalyses [70], and for the design of mesoporous films and nanoparticle arrays [71]. 

Figure 13.19 The template-directed self-assembly of Au clusters on silicon substrate patterned by constructive nanolithography.

In [55] a large-area fabrication of hexagonally ordered metal dot arrays with an area density of 10u/cm2 was demonstrated. The metal dots were produced by an electron beam evaporation followed by a lift-off process. The dots size was 20 nm dots with a 40 nm period by combining block copolymer nanolithography and a trilayer resist technique. A self-assembled spherical-phase block copolymer top layer spontaneously generated the pattern, acting as a template. The pattern was first transferred to a silicon nitride middle layer by reactive ion etch, producing holes. The nitride layer was then used as a mask to further etch into a polyamide bottom layer. 

Nanostructured polymers, in particular block copolymers, have immense potential in areas ranging from templating inorganic materials to permeation/ filtration media, nano-assaying, nanolithography and high density data storage media. 

In this chapter we provide a brief review of different nanolithography and nanomanipulation techniques. We discuss mainly such techniques as templated growth, dip pen lithography, anodic oxidation and scanning probe microscope based nanomanipulation. The chapter contains an introduction to the basic techniques followed by examples of such nanostructure growth. 

One of the most popular and probably the cheapest method of nanolithography is to use nanometer size templates that can be used to fabricate nanowires. In some... 

Making templates of ordered nanopores is the starting point for template based nanolithography. The next step involves filling the pores of the membrane with different materials of interest using one or more available methods. The methods include electrochemical deposition (ED), vapor phase deposition such as chemical vapor deposition (CVD), pressure injection of molten metals and sol-gel methods. In this section we describe some of the methods of deposition in the nanopores. 

Demers, L. M. Mirkin, C. A., Combinatorial templates generated by dip-pen nanolithography for the formation of two-dimensional particle arrays, Angew. Chem. Int. Ed. 2001, 40, 3069-3071... 

Most of the time, metal/dielectric nanocomposites are studied in the form of solutions or thin solid films on a substrate Colloids, doped and annealed glasses, sol-gels, surfactant-stabilized nanoparticles, micelles, two- or three-dimension self-assembled nanocomposites, self-organized mesoporous oxides filled with metals, electrochemically-loaded template membranes, metal-ion implanted crystals, nanocomposite films elaborated by laser ablation, cluster-beam deposition, radio-frequency sputtering, or nanolithography. 

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