Multimode hydrogen depassivation lithography: A method for optimizing atomically precise write times

Spurious dangling bond formation during atomically precise hydrogen depassivation lithography on Si(100): The role of liberated hydrogen

“…11 However, at HDL voltages below approximately 4.5 V and sufficiently high current, the HDL spot size becomes atomically precise and above a threshold somewhat independent of electron dose. 12 This work shows the formation of spurious DBs formation well outside the primary patterned area during these low voltage processes, 3,[11][12][13][14] an effect that is difficult to observe at higher voltages due to the tails of the high V spot. While much study has been devoted to the role of electron energy transfer in HDL, little has been devoted to the nature of the dissociative reaction products (liberated H) as described here.…”

Pattern transfer of hydrogen depassivation lithography patterns into silicon with atomically traceable placement and size control

“…To compensate for the partially exposed line edge proximity effect, hard mask templates were made using multimode HDL 22 with an abrupt line edge of approximately one dimer row, or 0.768 nm, of transition between fully passivated and fully depassivated areas as shown in Fig. 4.…”

“…16 However, conversion of these atomically precise adsorbates a) Email: jballard@zyvexlabs.com into three dimensional structures requires either repeated patterning, 14,17,18 annealing, 19 or less well resolved processes such as tip-based e-beam induced deposition. 22 At tip-sample bias below approximately 4.5 V, HDL linewidths comparable to the width of a single dimer row (0.768 nm) with atomically abrupt line edges having been shown; the narrow linewidth mode is here referred to as atomically precise mode (AP mode). 21 To produce 3D structures, HDL is used to produce atomically resolved reactive templates for etch resistant mask deposition, with the flexibility of HDL proving to be invaluable in achieving high resolution structures.…”

Machine learning at the (sub)atomic scale: next generation scanning probe microscopy

“…A major advance in autonomous probe microscopy was made by Mohammad Rashidi and Bob Wolkow at the University of Alberta in a ground-breaking paper published in 2018 [64], where they not only showed that a CNN framework could be used to identify image artefacts arising from a double (or multiple) tip but embedded the identification and classification algorithms in their STM control software. Their focus is on the H-passivated variant of the Si(100) surface discussed above, comprising rows of H-terminated dimers (see the sketch in figure 4); the resulting H:Si(100)-(2x1) surface [65] has been studied extensively in the context of atomic scale lithography [66][67][68][69][70], single atom electronics [71,72], and fundamental quantum mechanics (including quantum information [73,74]). Desorption of single H atoms is possible via injection of electrons from the STM tip, leading to vibrational heating, and ultimately dissociation, of the H-Si bond.…”