Dieleman Christian D, Ding Weiyi, Wu Lianjia, Thakur Neha, Bespalov Ivan, Daiber Benjamin, Ekinci Yasin, Castellanos Sonia, Ehrler Bruno
AMOLF, Center for Nanophotonics, Science Park 104, 1098XG Amsterdam, The Netherlands.
Advanced Research Center for Nanolithography, EUV Photoresists Group, Science Park 106, 1098 XG Amsterdam, The Netherlands.
Nanoscale. 2020 May 28;12(20):11306-11316. doi: 10.1039/d0nr01077d.
Colloidal quantum dots have found many applications and patterning them on micro- and nanoscale would open a new dimension of tunability for the creation of smaller scale (flexible) electronics or nanophotonic structures. Here we present a simple, general, one-step top-down patterning technique for colloidal quantum dots by means of direct optical or electron beam lithography. We find that both photons and electrons can induce a solubility switch of both PbS and CdSe quantum dot films. The solubility switch can be ascribed to cross-linking of the organic ligands, which we observe from exposure with deep-UV photons (5.5 eV) to extreme-UV photons (91.9 eV), and low-energy (3-70 eV) as well as highly energetic electrons (50 keV). The required doses for patterning are relatively low and feature sizes can be as small as tens of nanometers. The luminescence properties as well as carrier lifetimes remain similar after patterning.
胶体量子点已得到广泛应用，在微米和纳米尺度上对其进行图案化将为创建更小尺寸（柔性）电子器件或纳米光子结构开辟新的可调谐维度。在此，我们展示了一种通过直接光学或电子束光刻对胶体量子点进行简单、通用的一步自上而下图案化技术。我们发现光子和电子均可诱导PbS和CdSe量子点薄膜的溶解度转变。这种溶解度转变可归因于有机配体的交联，我们观察到从深紫外光子（5.5 eV）到极紫外光子（91.9 eV），以及低能（3 - 70 eV）和高能电子（50 keV）的照射都会引发这种交联。图案化所需剂量相对较低，特征尺寸可小至几十纳米。图案化后发光特性以及载流子寿命保持相似。
