Detecting and Directing Single Molecule Binding Events on H-Si(100) with Application to Ultradense Data Storage

Abstract

Many new material systems are being explored to enable smaller, more capable and energy efficient devices. These bottom up approaches for atomic and molecular electronics, quantum computation, and data storage all rely on a well-developed understanding of materials at the atomic scale. Here, we report a versatile scanning tunneling microscope (STM) charge characterization technique, which reduces the influence of the typically perturbative STM tip field, to develop this understanding even further. Using this technique, we can now observe single molecule binding events to atomically defined reactive sites (fabricated on a hydrogen-terminated silicon surface) through electronic detection. We then developed a new error correction tool for automated hydrogen lithography, directing molecular hydrogen binding events using these sites to precisely repassivate surface dangling bonds (without the use of a scanned probe). We additionally incorporated this molecular repassivation technique as the primary rewriting mechanism in new ultra-dense atomic data storage designs (0.88 petabits per in 2 ).

Ionic charge distributions in silicon atomic surface wires

“…The left configuration (−0, ud) appeared for only a few line scans resulting in greater noise seen in the line profile, with the right configuration (0−, du) never appearing in this dataset, possibly due to the unseen presence of a local electrostatic perturbation from subsurface charges making the negative charge favour a side. 17,21 The blue curve has been drawn to highlight the expected configuration. Full Δf (V) spectroscopies and Δf (V) line scan maps are shown in Fig.…”

“…The atomic force microscope (AFM) has been proven to be a useful tool capable of detecting discrete single-electron charge transitions in both molecular [9][10][11][12][13] and atomic structures, [14][15][16] including patternable silicon dangling bonds (DBs) 6,[17][18][19] on a hydrogen-terminated surface. A DB is patterned through atomically precise removal of a surface hydrogen atom through current injection from an atomically sharp tip [20][21][22][23][24][25] leaving a single unsatisfied bond which extends into vacuum. Previous AFM studies have examined DBs, showing readout and manipulation of its quantized charge states through both electrostatic interactions with other local fixed charges (such as other DBs), or the probe tip.…”

Ring charging of a single silicon dangling bond imaged by noncontact atomic force microscopy

“…An ultimate confined system is a surface adatom dangling bond (DB) consisting of a single electronic state in the bandgap of a semiconductor, whose charging can be controlled by a scanning-probe microscope [10,11]. DBs have been proposed for binary logic [12] and data storage [13,14] applications. They reveal a rich fundamental physics, such as polaronic transport [15,16] and carrier dynamics [17,18].…”

Dangling bonds on the Cl- and Br-terminated Si(100) surfaces

“…The controlled change of the DB charge state allows to study interesting and complex physical phenomena, making the DBs attractive from the fundamental point of view [7][8][9][10] . From the practical point of view, DBs are promising for many applications in atomic scale silicon-based electronic devices due to the well-developed process of their precise creation on Si(100)-2×1-H [11][12][13][14] .…”