Scanning probe microscope lithography at the micro- and nano-scales

J Nanosci Nanotechnol. 2010 Jul;10(7):4486-94. doi: 10.1166/jnn.2010.2359.

Abstract

Scanning probe microscopy (SPM)-based lithography at the micro- and nano-scales is presented. Our method in SPM local oxidation involves two SPM tips, one having a robust blunt tip, a "micrometer tip," and the other having a sharp tip, a "nanometer tip." In tapping-mode SPM local oxidation experiments, Si oxide wires with sub-10 nm resolution were produced by precisely tuning the dynamic properties of the nanometer tip such as drive amplitude and quality factor. On the other hand, in order to perform large-scale oxidation, SPM tip with a contact area of microm2, which is about 10(4) times larger than that of the conventional nanometer tip, was prepared. We propose and demonstrate a method of performing micrometer-scale SPM local oxidation using the micrometer tip under contact-mode operation. The width of the Si oxide produced was clearly determined by the contact length of the tip. Furthermore, we explore the possibility of performing the sub-20 nm lithography of Si surfaces using SPM scratching with a diamond-coated tip. The influence of various scan parameters on the groove size was investigated. The groove size could be precisely controlled by the applied force, scan direction, and the number of scan cycles. There is no effect of the scan speed on the groove size. It is concluded that high-speed nanolithography can be achieved without the degradation of patterns by SPM scratching. SPM-based lithography has the advantage of being able to fabricate a desired structure at an arbitrary position on a surface and plays an important role for bridging the gap between micro- and nano-scales.