Lithography miniaturization

The pursuit of further miniaturization of dectronic circuits has made submicrometer resolution lithography a crucial dement in future computer engineering. LB films have long been considered potential candidates for resist applications, because conventional spin-coated photoresist materials have large pinhole densities and variations of thickness. In contrast, LB films are two-dimensional, layered, crystalline solids that provide high control of film thickness and are impermeable to plasma down to a thickness of 40 nm (46). The electron beam polymerization of (Q-tricosenoic acid monolayers has been mentioned. Another monomeric amphiphile used in an attempt to develop dectron-beam-resist materials is a-octadecylacryhc acid (8). 

To further miniaturize the sensors, nanotechniques such as surface probe microscopy and lithography, lateral force microscopy, atomic force microscopy (AFM), and AFM lithography can be utilized.46 Nanoimprint lithography is a low-cost technique that has been shown to produce patterns on the nanometer scale.98 99... 

In 2002, Burghard and coworkers described an elegant method for the electrochemical modification of individual SWCNTs [177]. To address electrically individual SWCNTs and small bundles, the purified tubes were deposited on surface-modified Si/Si02 substrates and subsequently contacted with electrodes, shaped by electron-beam lithography. The electrochemical functionalization was carried out in a miniaturized electrochemical cell. The electrochemical reduction was achieved by reduction of 4-N02C6H4N2+BF4 in DMF with NBu4+BF4 as the electrolyte (Scheme 1.27a), anodic oxidation was accomplished with aromatic amines in dry ethanol with LiC104 as the electrolyte salt (Scheme 1.27b) [177]. 

In current semiconductor fabrication, photolithography with 193 nm UV irradiation is able to pattern features that are 37 nm wide. However, the rapid miniaturization of ICs demands improvements in photolithography in order to sharpen the line resolution at size regimes far below 37 nm (Figure4.30). Although immersion lithography has been suggested as a candidate for sub-50-nm line resolution, there... 

Epitaxy—The growth of crystalline layers of semiconducting materials in a layered structure. Integrated circuits—Complex electronic circuits fabricated using multiple growth and lithography/ pattern transfer stages to produce many miniature electronic elements on a monolithic device. 

Chemical, thermal, photochemical and structural stability one-step procedure at ambient or low temperature Control of pore size and morphology high electro chemical active surface area high conductivity suitable for development of miniaturized biosensor devices Suitable for miniaturization enhanced sensitivity low cost production (usually lithography)... 

The processability of certain CEPs has been utilized in the construction of microsystems, particularly miniature sensor systems. For example, simply dip-coating connecting platinum wires with a polyaniline formulation produces a useful humidity sensor.133 CEPs can also be screen-printed or ink-jet-printed to produce the complex shapes needed for various devices. Electrodeposition of CEPs is also a popular processing method, and this technique is compatible with conventional MEMS fabrication, where lithography and etching can be used to prepattern metal electrodes. Subsequent deposition of CEP by electrochemical polymerization produces the CEP microdevice.129... 

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