High-resolution bubble printing of quantum dots


Semiconductor quantum dots (QDs) feature excellent properties such as high quantum efficiency, tunable emission frequency and good fluorescence stability. Incorporation of QDs into new devices relies upon high-resolution and high-throughput patterning techniques. Herein, we report a new printing technique known as bubble printing (BP), which exploits a light-generated microbubble at the interface of colloidal QD solution and a substrate to directly write QDs into arbitrary patterns. With the uniform plasmonic hot-spot distribution for high bubble stability and the optimum light-scanning parameters, we have achieved full-color QD printing with sub-micron resolution (650nm), high throughput (scanning rate of ~10-2 m/s), and high adhesion of the QDs to the substrates. The printing parameters can be optimized to further modify the fluorescence properties of the patterned QDs such as emission wavelength and lifetime. The patterning of QDs on flexible substrates further demonstrates the wide applicability of this new technique. Thus, BP technique addresses the barrier of achieving a widely applicable, high-throughput and user-friendly patterning technique in the sub-micrometer regime, along with simultaneous fluorescence modification capability.

Journal article
ACS Applied Materials & Interfaces