Super-resolution Monitoring of React-on-demand Photo-assisted Electrochemical Printing via Microsphere Nanoscopy

Nanoscale material surface patterning on semiconductor requires multi-scale measurements for the determination of their geometric dimensions and shapes. In this paper, we propose an in-situ,real-time super-resolution imaging technique using a simple microsphere microlens to monitor the dynamic process of photo-assisted electrochemical printing in a microfluidic chip. The microsphere microlens with diameters of 30 ~ 60 $\mu$ m were set close to a semiconductor surface to image the electrochemical printing process underneath. With the microsphere-based imaging system, both the depositing process of silver nanoparticles with 200 nm ~ 300 nm in diameter and the growing process of silver belts were observed. Also, we experimentally observed how a typical 120° angle formed at the terminal of a silver belt through the microsphere superlens. Super-resolution monitoring ability provided by microsphere lens will shine a light on the sub-diffraction process of micro/nano fabrication.