Development of 3-dimensional nanopatterning technology with ultra-high resolution and its applications for electrical/optical devices

Abstract

The development of large-area nano-patterning with high resolution, high aspect ratio and simple process scheme/cost is a challenging work for realizing their potential applications in opto-electronics and nano-biotechnology such as nanoelectronics, optics, optical sensing, light-emitting devices and bio-sensing devices. Several approaches towards nanostructure fabrication have been exploited without resorting to expensive tools such as those used in deep-UV projection lithography and electron-beam lithography. In this thesis, new nanolithographic technology for fabricating high-aspect ratio complex nanostructures with 10nm scale features and fabrication of electrical/optical applications by nanopatterning method are discussed. A novel patterning technology named “secondary sputtering lithography(SSL)” was developed by combining secondary sputtering phenomenon and soft lithography, and advanced researches for more complex SSL structures is conducted. In order to verify the utility and possibilities of applications of SSL patterns, some application researches for transparent electrodes, alignment of Liquid crystal were carried out. And, fabrication of carbon nanotube based field effect transistor (CNT-FET) by using nanopattern of soft-lithography has challenged through tuning the electric field. Firstly, Secondary sputtering lithography(SSL) was firstly developed and introduced by our group, that enables fabrication of ultrahigh-resolution (ca. 10nm) and high aspect ratio(ca. 15) patterns of 3-dimensional carious shapes by using secondary sputtering phenomenon at ion-bombardment. In other words, the secondary sputtering lithography method uses concepts of accerated Ar ion-assisted bombardment, which leads to the attachment of target materials to the side surfaces of prepatterned polymers fabricated by using a PDMS mold. Unlike other nano-fabrication techniques described thus far, this technique has several notable advantages. Firstly, the simple processing pr...