Monolayer-induced band bending in the near-surface region of Ge(111)

2011 ◽  
Vol 83 (24) ◽  
Author(s):  
A. J. Mäkinen ◽  
G. P. Kushto
Keyword(s):  
Surface Region ◽  
Band Bending ◽  
Near Surface

scholarly journals Оптические и электронные свойства пассивированных поверхностей InP(001)

2021 ◽  
Vol 55 (8) ◽  
pp. 644
Author(s):  
П.А. Дементьев ◽  
Е.В. Дементьева ◽  
Т.В. Львова ◽  
В.Л. Берковиц ◽  
М.В. Лебедев
Keyword(s):  
Aqueous Solution ◽  
Electronic Properties ◽  
Surface Region ◽  
Alcoholic Solution ◽  
Surface Band ◽  
Band Bending ◽  
Near Surface ◽  
Ammonium Sulfide ◽  
Optical And Electronic Properties ◽  
Chemical Passivation

The effect of chemical passivation in solutions of ammonium sulfide (NH4)2S on the optical and electronic properties of the n-InP (001) surface has been studied. It has been shown that treatment in a 4% aqueous solution of (NH4)2S leads to a decrease of surface band bending and localized charges in near-surface region in the 2 times. Processing in a 4% alcoholic solution of (NH4)2S leads to a decrease in these parameters in 3 times, and moreover, the barrier photovoltage and also reduces in three times.

Anodic sulfidation and model characterisation of GaAs (100) in (NH4)2 Sx solution

1999 ◽  
Vol 573 ◽  
Author(s):  
R. F. Elbahnasawy ◽  
J. G. Mclnerney ◽  
P. Ryan ◽  
G. Hughes ◽  
M. Murtagh
Keyword(s):  
Photoelectron Spectroscopy ◽  
Structural Model ◽  
Thick Layer ◽  
Surface Region ◽  
Optoelectronic Device ◽  
Native Oxide ◽  
Surface Barrier ◽  
Surface Band ◽  
Band Bending ◽  
Near Surface

ABSTRACTElectrochemical sulfidation of n-type GaAs (100) has been investigated under anodic conditions with a view to surface passivation for improved electronic and optical properties. This treatment has successfully removed the native oxide and formed a thick layer of gallium and arsenic sulfides displaying high durability against oxidation and optical degradation compared to conventional dipping treatment using (NH4)2S solution. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), secondary ion mass spectroscopy (SIMS) and atomic force microscopy (AFM) have been used to characterize the treated surfaces. These studies have been used to devise a structural model of the near-surface region. The results of Raman backscattering spectroscopy measurements indicate that there is a 35% reduction of the surface barrier height compared to the untreated surface. This passivation technique has been shown to be effective in reducing surface band bending on GaAs (100) and enhancing the chemical stability of the surface, making it more suitable for electronic and optoelectronic device applications.

Preparation of cross-sectional samples for near-surface TEM studies

1987 ◽  
Vol 45 ◽  
pp. 380-381
Author(s):  
R.C. Dickenson ◽  
K.R. Lawless
Keyword(s):  
Standard Sample ◽  
Surface Region ◽  
Specimen Preparation ◽  
Thick Sheet ◽  
Drill Bit ◽  
Sample Holder ◽  
Metal Interface ◽  
Cross Sectional ◽  
Near Surface ◽  
Cold Worked

In thermal oxidation studies, the structure of the oxide-metal interface and the near-surface region is of great importance. A technique has been developed for constructing cross-sectional samples of oxidized aluminum alloys, which reveal these regions. The specimen preparation procedure is as follows: An ultra-sonic drill is used to cut a 3mm diameter disc from a 1.0mm thick sheet of the material. The disc is mounted on a brass block with low-melting wax, and a 1.0mm hole is drilled in the disc using a #60 drill bit. The drill is positioned so that the edge of the hole is tangent to the center of the disc (Fig. 1) . The disc is removed from the mount and cleaned with acetone to remove any traces of wax. To remove the cold-worked layer from the surface of the hole, the disc is placed in a standard sample holder for a Tenupol electropolisher so that the hole is in the center of the area to be polished.

The Effects of Ion Implantation on the Surface Features of Inconel 600

1985 ◽  
Vol 43 ◽  
pp. 288-289
Author(s):  
John D. Rubio
Keyword(s):  
Grain Boundary ◽  
Ion Implantation ◽  
Nuclear Power ◽  
Power Plants ◽  
Surface Region ◽  
Selective Dissolution ◽  
Boundary Region ◽  
Near Surface ◽  
Inconel 600 ◽  
Steam Generator Tubing

The degradation of steam generator tubing at nuclear power plants has become an important problem for the electric utilities generating nuclear power. The material used for the tubing, Inconel 600, has been found to be succeptible to intergranular attack (IGA). IGA is the selective dissolution of material along its grain boundaries. The author believes that the sensitivity of Inconel 600 to IGA can be minimized by homogenizing the near-surface region using ion implantation. The collisions between the implanted ions and the atoms in the grain boundary region would displace the atoms and thus effectively smear the grain boundary.To determine the validity of this hypothesis, an Inconel 600 sample was implanted with 100kV N2+ ions to a dose of 1x1016 ions/cm2 and electrolytically etched in a 5% Nital solution at 5V for 20 seconds. The etched sample was then examined using a JEOL JSM25S scanning electron microscope.

Microstructural changes of Aluminum Nitride after laser irradiation and electroless copper deposition

1994 ◽  
Vol 52 ◽  
pp. 636-637
Author(s):  
S. Cao ◽  
A. J. Pedraza ◽  
L. F. Allard
Keyword(s):  
Aluminum Nitride ◽  
Laser Irradiation ◽  
Electroless Deposition ◽  
Thermal Evaporation ◽  
Surface Region ◽  
Near Surface ◽  
Laser Patterning ◽  
Electroless Copper ◽  
Excimer Laser Irradiation ◽  
Laser Effect

Excimer-laser irradiation strongly modifies the near-surface region of aluminum nitride (AIN) substrates. The surface acquires a distinctive metallic appearance and the electrical resistivity of the near-surface region drastically decreases after laser irradiation. These results indicate that Al forms at the surface as a result of the decomposition of the Al (which has been confirmed by XPS). A computer model that incorporates two opposing phenomena, decomposition of the AIN that leaves a metallic Al film on the surface, and thermal evaporation of the Al, demonstrated that saturation of film thickness and, hence, of electrical resistance is reached when the rate of Al evaporation equals the rate of AIN decomposition. In an electroless copper bath, Cu is only deposited in laser-irradiated areas. This laser effect has been designated laser activation for electroless deposition. Laser activation eliminates the need of seeding for nucleating the initial layer of electroless Cu. Thus, AIN metallization can be achieved by laser patterning followed by electroless deposition.

Annealing Effects at the Near-Surface Region of Gallium Arsenide

1992 ◽  
Vol 105-110 ◽  
pp. 1383-1386 ◽  
Author(s):  
Hugh E. Evans ◽  
D.L. Smith ◽  
P.C. Rice-Evans ◽  
G.A. Gledhill ◽  
A.M. Moore
Keyword(s):  
Gallium Arsenide ◽  
Surface Region ◽  
Near Surface ◽  
Annealing Effects

scholarly journals Interactions of Ruddlesden-Popper Phases and Migration-Induced Field-Stabilized Polar Phase in Strontium Titanate

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 693
Author(s):  
Christian Ludt ◽  
Elena Ovchinnikova ◽  
Anton Kulikov ◽  
Dmitri Novikov ◽  
Sibylle Gemming ◽  
...  
Keyword(s):  
Strontium Titanate ◽  
Density Functional ◽  
Surface Region ◽  
Point Of View ◽  
Polar Phase ◽  
Near Surface ◽  
Atomic Displacements ◽  
Induced Field ◽  
And Migration ◽  
Novel Concept

This work focuses on the validation of a possible connection of the known Ruddlesden-Popper (RP) phases and the novel concept of the migration-induced field-stabilized polar (MFP) phase. To study this subject, model structures of RP phases in bulk strontium titanate are analyzed by means of density functional theory (DFT). The obtained geometries are compared to experimental MFP data. Good agreement can be found concerning atomic displacements in the pm range and lattice strain inferred by the RP phases. Looking at the energy point of view, the defect structures are on the convex hull of the Gibb’s free energy. Although the dynamics to form the discussed defect models are not addressed in detail, the interplay and stability of the described defect model will add to the possible structure scenarios within the near-surface region of strontium titanate. As a result, it can be suggested that RP phases generally favor the MFP formation.

Electronic Impact of Inclusions in Diamond

2009 ◽  
Vol 1203 ◽  
Author(s):  
Erik M. Muller ◽  
John Smedley ◽  
Balaji Raghothamachar ◽  
Mengjia Gaowei ◽  
Jeffrey W. Keister ◽  
...  
Keyword(s):  
Charge Trapping ◽  
Secondary Phase ◽  
Surface Region ◽  
Phase Region ◽  
Electron Trapping ◽  
Near Surface ◽  
X Ray ◽  
Photoconductive Gain ◽  
Single Crystal Diamond ◽  
Topography Data

AbstractX-ray topography data are compared with photodiode responsivity maps to identify potential candidates for electron trapping in high purity, single crystal diamond. X-ray topography data reveal the defects that exist in the diamond material, which are dominated by non-electrically active linear dislocations. However, many diamonds also contain defects configurations (groups of threading dislocations originating from a secondary phase region or inclusion) in the bulk of the wafer which map well to regions of photoconductive gain, indicating that these inclusions are a source of electron trapping which affect the performance of diamond X-ray detectors. It was determined that photoconductive gain is only possible with the combination of an injecting contact and charge trapping in the near surface region. Typical photoconductive gain regions are 0.2 mm across; away from these near-surface inclusions the device yields the expected diode responsivity.

scholarly journals Enhanced Diffusion of Dopants in Vacancy Supersaturation Produced by MeV Implantation

1997 ◽  
Vol 469 ◽  
Author(s):  
V. C. Venezia ◽  
T. E. Haynes ◽  
A. Agarwal ◽  
H. -J. Gossmann ◽  
D. J. Eaglesham
Keyword(s):  
Surface Layer ◽  
Surface Region ◽  
Silicon On Insulator ◽  
Rich Region ◽  
Near Surface ◽  
Enhanced Diffusion ◽  
Float Zone ◽  
Transient Enhanced Diffusion

ABSTRACTThe diffusion of Sb and B markers has been studied in vacancy supersaturations produced by MeV Si implantation in float zone (FZ) silicon and bonded etch-back silicon-on-insulator (BESOI) substrates. MeV Si implantation produces a vacancy supersaturated near-surface region and an interstitial-rich region at the projected ion range. Transient enhanced diffusion (TED) of Sb in the near surface layer was observed as a result of a 2 MeV Si+, 1×1016/cm2, implant. A 4× larger TED of Sb was observed in BESOI than in FZ silicon, demonstrating that the vacancy supersaturation persists longer in BESOI than in FZ. B markers in samples with MeV Si implant showed a factor of 10× smaller diffusion relative to markers without the MeV Si+ implant. This data demonstrates that a 2 MeV Si+ implant injects vacancies into the near surface region.

scholarly journals Anomalous Grazing X-ray Reflectometry for Determining the Number Density of Atoms in the Near-Surface Region

1996 ◽  
Vol 37 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Masatoshi Saito ◽  
Eiichiro Matsubara ◽  
Yoshio Waseda
Keyword(s):  
Surface Region ◽  
Number Density ◽  
Near Surface ◽  
X Ray
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