Fig. 3: ND trapping depends on hole diameter, but not hole depth.
From: Wafer-scale integration of single nanodiamonds via electrostatic-trapping
a Schematic illustrating the surface charge on the substrate and photoresist template that make up a patterned hole, where D and h indicate the hole diameter and depth, respectively. b Distribution of calculated electrostatic potential in the template hole. Dotted white lines outline the threshold potential region. Anywhere within the outlined region will effectively trigger ND movement. White arrow represents the minimal width of the effective trapping region. c Minimal trapping width increased linearly with hole diameter, D. d Minimal trapping width for a 3 µm diameter hole is stable across different hole depths, h. e SEM images of trapped NDs in hole templates of different diameters (column) and depths (rows). Hole diameter ranged from 3 µm to 6 µm while hole depth varied from 1.5 µm to 2.3 µm.
