Electron-beam lithographic features

The top-down method relies on standard lithographic processes, similar to the processes used in manufacturing CPUs. In this approach, electron beam lithographic technique is used to introduce the nanometer-sized features, which are realized by physically etching a single-crystalline silicon wafer [16]. On the contrary, the bottom-up processes start with the synthesis of SiNWs that are... 

In general there are two lithographic processes used in computer-circuit fabrication -photolithography and radiation (X-ray, laser, electron-beam and deep-UV (248- and 193-nm wavelength)) lithography. The principal difference is the radiation source and wavelength, which in turn define the feature size which can be achieved. 

Electron-beam lithography (EBL) refers to a lithographic patterning technique in which a focused beam of electrons is used to expose and pattern resist-coated semiconductor substrates as part of a number of steps used in the fabrication of IC devices. Its introduction into IC fabrication dates back to 1957. Today, electron-beam lithography is used primarily in fabrication of masks used in optical lithography and x-ray lithography. It is also used in low-volume fabrication of exploratory IC device layers with extremely small features it has also found application in nanotechnology research. 

It is also possible to smoothen the walls of patterned resist features, using standard post-lithographic processing techniques such as UV hardening, electron-beam irradiation, and thermal flow. The use of surfactant rinse liquids has also been shown to improve LER of patterned resist features to acceptable values. ... 

Lithographic methods (near-UV photolithography or electron beam lithography) can also yield topologies at this size scale. The latter technique does not need a mask and can produce array features of 30-40 nm in dimension (Norman and Desai 2006). 

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