Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, 84112, USA.
Phys Rev Lett. 2011 Nov 11;107(20):205501. doi: 10.1103/PhysRevLett.107.205501. Epub 2011 Nov 7.
By saturating a photochromic transition with a nodal illumination (wavelength, λ), one isomeric form of a small molecule is spatially localized to a region smaller than the far-field diffraction limit. A selective oxidation step effectively locks this pattern allowing repeated patterning. Using this approach and a two-beam interferometer, we demonstrate isolated lines as narrow as λ/8 (78 nm) and spacing between features as narrow as λ/4 (153 nm). This is considerably smaller than the minimum far-field diffraction limit of λ/2. Most significantly, nanopatterning is achieved via single-photon reactions and at low light levels, which in turn allow for high throughput.
通过节点照明（波长为 λ）使光致变色跃迁饱和，可以将小分子的一种异构体空间局域到小于远场衍射极限的区域。选择性氧化步骤有效地锁定了这种图案，从而可以进行重复的图案化。使用这种方法和双光束干涉仪，我们证明了线宽可以窄至 λ/8（78nm），特征之间的间距可以窄至 λ/4（153nm）。这明显小于远场衍射极限的 λ/2。最重要的是，纳米图案化是通过单光子反应和低光水平实现的，这反过来又允许高吞吐量。
