Microdomain lithography

Although e-beam lithography can give excellent spatial control of functional microdomains, this direct-write patterning process is not time-efficient for large-area integration of functional devices. Techniques for rapid patterning of functional nanostructures are thus needed for real-time applications. Ober et al. [106-108] have successfully developed a novel block copolymer... 

Lithography with a Pattern of Block Copolymer Microdomains as a Positive or Negative Resist... 

As discussed previously, vertically oriented cylinders are preferred for many applications in lithography, such as the patterning of vias, contact holes, or bit-patterned media. If neither block in the block copolymer is preferentially attracted to the substrate, the microdomains... 

Lithography with Self-Assembled Block Copolymer Microdomains... 

A further motivation to writing this chapter has been the use of copolymer lithography by researchers at the Corporate Research and Development Center of the Toshiba Corporation. Section 9.7 [6] details their clever use of copolymer lithography for information storage. These researchers demonstrate that CoCrPt films can be patterned without difficulty on hard-drive platters that have been embossed for microdomain templating. While apphcations such as this were one of the motivations for academic work over the past decade, until recently there has been a paucity of projects with a truly apphed focus. 

Perhaps the earliest contribution to the control of microdomain orientation via interface control was the experiments of Mansky et al. [5], who demonstrated that cylindrical microdomains could be oriented perpendicular to a film by solvent casting on an aqueous surface. It was also demonstrated here that ozone could be used to selectively remove PB microdomains from a PS matrix, thereby enabling subsequent research in lithography. However, the uniformity of this sample preparation method was highly lacking - only certain randomly distributed regions of samples prepared in this manner yielded perpendicularly orinted cylinders. 

Thomas and coworkers [62] have used a novel application of microfluidic technology to begin to control microdomain array orientation. Standard soft lithography techniques were used to fabricate microfluidic channels out of poly (dimethyl siloxane) (PDMS) that were placed onto a semiconductor wafer [63]. Polymer solutions were allowed to flow into the channels and the solvent... 

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