Shirakashi Jun-ichi
Department of Electrical and Electronic Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
J Nanosci Nanotechnol. 2010 Jul;10(7):4486-94. doi: 10.1166/jnn.2010.2359.
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.
介绍了基于扫描探针显微镜(SPM)的微米和纳米尺度光刻技术。我们在SPM局部氧化中的方法涉及两个SPM尖端,一个是具有坚固钝头的“微米尖端”,另一个是尖锐尖端的“纳米尖端”。在轻敲模式SPM局部氧化实验中,通过精确调整纳米尖端的动态特性,如驱动振幅和品质因数,制备出了分辨率低于10纳米的氧化硅线。另一方面,为了进行大规模氧化,制备了接触面积为微米²的SPM尖端,其比传统纳米尖端的接触面积大10⁴倍左右。我们提出并演示了一种在接触模式操作下使用微米尖端进行微米尺度SPM局部氧化的方法。所产生的氧化硅宽度明显由尖端的接触长度决定。此外,我们探索了使用涂覆金刚石的尖端进行SPM划痕对硅表面进行亚20纳米光刻的可能性。研究了各种扫描参数对沟槽尺寸的影响。沟槽尺寸可以通过施加的力、扫描方向和扫描循环次数精确控制。扫描速度对沟槽尺寸没有影响。得出的结论是,通过SPM划痕可以实现高速纳米光刻而不会使图案退化。基于SPM的光刻技术具有能够在表面的任意位置制造所需结构的优点,并且在弥合微米和纳米尺度之间的差距方面发挥着重要作用。