The scanning tunneling microscope has been used to desorb hydrogen from hydrogen-terminated silicon (100) surfaces. As a result of control the dose incident electrons, countable number desorption sites can be created and yield cross section are thereby obtained. Two distinct mechanisms observed: (i) direct electronic excitation Si-H bond by field-emitted electrons (ii) an atomic resolution mechanism that involves multiple-vibrational at low applied voltages. This vibrational heating effect...

Nanoscale patterning of the hydrogen terminated Si(100)-2×1 surface has been achieved with an ultrahigh vacuum scanning tunneling microscope. Patterning occurs when electrons field emitted from probe locally desorb hydrogen, converting into clean silicon. Linewidths 1 nm on a 3 pitch are by this technique. Local chemistry is also demonstrated selective oxidation patterned areas. During oxidation, linewidth preserved and surrounding H-passivated regions remain unaffected, indicating potential...

Recent advances in the technology and understanding of ohmic contacts for a variety III–V compound semiconductor material systems are reviewed. Special attention is focused on factors critical issues involved making low resistance reliable contacts. The solid-phase regrowth mechanisms key metallization described. In addition, special techniques to improve discussed. Finally, reliability addressed.

Submonolayer coverages of Al were evaporated onto hydrogen-terminated $\mathrm{Si}(001)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}1)$ surfaces and studied by scanning tunneling microscopy (STM). Nanoscale patterns bare Si created STM desorption hydrogen, the size number density islands on monohydride areas surface compared. Dramatic differences in island nucleation are observed which suggest that diffusion length adatoms region is much longer than Si. With lowered deposition rates or...

Phosphorous δ-doping layers were fabricated in silicon by PH3 deposition at room temperature, followed low-temperature Si epitaxy. Scanning tunneling microscope images indicate large H coverage, and regions of c(2×2) structure. Hall data imply full carrier activation with mobility <40 cm2/V s when the surface coverage is ≲0.2 ML. Conductivity measurements show a ln(T) behavior low temperatures, characteristic high-density two-dimensional conductor. Possible future applications to...

Ultrathin oxide patterns of a linewidth 50 Å have been created on Si(100)-2×1 surfaces by scanning tunneling microscope operating in ultrahigh vacuum. The thickness is estimated to be 4–10 Å. morphology and spectroscopy the region are obtained. Hydrogen passivation used as an oxidation mask. defects caused passivated before after hydrogen desorption compared discussed. multistep silicon processings vacuum micropscope thus demonstrated.

Single-electronics and quantum computers have tremendous potential, but obstacles to fabricating them are enormous. Here we consider the physical difficulties in terms of both circuit architecture plausible future advancements silicon technology. Our discussion will focus on a set recent proposals which involve tunnelling between 2D arrays Coulomb islands or ‘quantum dots’. Planar architectures this type can potentially be realized through situ e-beam patterning self-ordered dopant precursor...

A nanoscale fabrication process compatible with present Si technology is reported. Preimplanted contact arrays provide external leads for scanning tunneling microscope (STM)-defined dopant patterns. The STM’s low energy electron beam removes hydrogen from H terminated Si(100) surfaces selective adsorption of PH3 precursor molecules, followed by room temperature overgrowth and 500 °C rapid thermal anneal to create activated P-donor patterns in As+-implanted lines. Electrical magnetoresistance...

Drones are used in complex scenes different scenarios. Efficient and effective algorithms required for drones to track targets of interest protect allied a versus game. This study physical models quadcopters scene engines investigate the resulting performance attacker defensive based on deep reinforcement learning. The learning network soft actor-critic was applied association with proposed reward penalty functions according design scenario. AirSim UAV modeling mission scenarios Unreal...

Si deposition on H terminated Si(100)-2x1 and 3x1 surfaces at temperatures 300-530 K is studied by scanning tunneling microscopy. Hydrogen apparently hinders adatom diffusion enhances surface roughening. The post-growth annealing effect analyzed. shown to remain the growth front up least 10 ML. dihydride units further suppress increase roughness.

Two-dimensional electron systems fabricated from a single layer of P-donors have been lithographically confined to nanometer scale in lateral directions. The electronic transport such quasi-one-dimensional with and without perpendicular magnetic field was characterized at cryogenic temperatures. Experimental data fit well two-dimensional weak localization interaction theory when the phase coherence length is shorter than smaller dimension confinement. Below transition temperature wire...

The scanning tunneling microscope is used to study the boron-doped Si(111) surface as a function of annealing times and temperatures. structure found be determined by concentration B. When substitutional B less than 1% top 1\ifmmode\times\else\texttimes\fi{}1 bilayer atoms, largely 7\ifmmode\times\else\texttimes\fi{}7 but surrounded adatom-covered regions (which have higher concentration). more 3%, whole will including (\ensuremath{\surd}3 \ifmmode\times\else\texttimes\fi{}...

Scanning tunneling microscope is used to create local surface modifications by means of ion impact damage. Graphite has been as a test case demonstrate this sputtering. Using 0.1-μs voltage pulse −30 −140 V applied the sample in rough vacuum 10−2 Torr, confined area damage (typically about 100 Å diameter) usually obtained. The damaged consists several layers terraces. Defects size few atoms can also be found. Electronic perturbations caused defects form superlattices with spacing three times...