Plasmons in Graphene Nanostructures with Point Defects and Impurities

ABSTRACTMicrodefects in multicrystalline silicon grown by directional solidification have been investigated by transmission electron microscopy. Their density (=106 cm−2) correlates with the density of shallow etch pits observed after chemomechanical polishing and selective etching. Different types of microdefects (size 10 – 100 nm) could be identified: i) spherical precipitates most likely amorphous silicon dioxide, ii) small plates lying on {111} planes and iii) groups of closely spaced stacking faults having the character of dipoles. It is argued that these defects are the result of agglomeration process of intrinsic point defects and impurities, where oxygen and carbon are the main candidates. A qualitative comparison to the point defects agglomeration observed in Cz material will be given.

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Hydrogen Interaction with Point Defects in the Si-SiO2 Structures and its Influence on the Interface Properties

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.131-133.345 ◽

2007 ◽

Vol 131-133 ◽

pp. 345-350 ◽

Cited By ~ 2

Author(s):

Daniel Kropman ◽

E. Mellikov ◽

Tiit Kärner ◽

Ü. Ugaste ◽

Tony Laas ◽

...

Keyword(s):

Point Defects ◽

Hydrogen Adsorption ◽

Impurity Content ◽

Magnetic Interaction ◽

Interface Properties ◽

Extended Defects ◽

Oxidation Condition ◽

Paramagnetic Impurities ◽

Defects And Impurities ◽

P Type

The type and density of the point defects that are generated in the Si surface layer during thermal oxidation depend on the oxidation condition: temperature, cooling rate, oxidation time, impurity content. Interaction between the point defects with extended defects and impurities affects the SiO2 structure and Si-SiO2 interface properties. Hydrogen adsorption on n- and p- type wafers is different. One possible reason for that can be the strength of the magnetic interaction between the hydrogen and paramagnetic impurities of the adsorbent. The influence of point defects and impurities may be diminished and the interface properties improved by an appropriate choice of the oxidation conditions and postoxidation laser irradiation.

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Ion-beam-assisted growth of doped Si layers

Journal of Materials Research ◽

10.1557/jmr.1988.1212 ◽

1988 ◽

Vol 3 (6) ◽

pp. 1212-1217 ◽

Cited By ~ 44

Author(s):

F. Priolo ◽

A. La Ferla ◽

E. Rimini

Keyword(s):

Activation Energy ◽

Growth Rate ◽

Point Defects ◽

Ion Beam ◽

Target Temperature ◽

Defects And Impurities

The growth of preamorphized silicon layers doped by multiple energy implants of boron, phosphorus, and boron plus phosphorus ions was investigated under irradiation with a 600 keV Kr+ + beam. The target temperature was set in the range 250–450 °C. During irradiation the growth was measured in situ by transient reflectivity. Boron and phosphorus at a concentration of 1 × 1020/cm3 enhance the rate by a factor of 3 and 2, respectively, whilst in compensated samples the rate is still more than a factor of 2 higher than in intrinsic or Ge-doped samples. This growth rate is characterized by an activation energy of 0.32 ± 0.05 eV which is, within the experimental uncertainties, independent of the dopant. The results are tentatively explained in terms of an interaction between generated point defects and impurities that increases the lifetime of defects at the crystal–amorphous interface.

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Interaction between point defects, extended defects and impurities in the Si–SiO2 system during the process of its formation

Thin Solid Films ◽

10.1016/j.tsf.2003.12.093 ◽

2004 ◽

Vol 459 (1-2) ◽

pp. 53-57

Author(s):

D Kropman ◽

T Kärner ◽

U Abru ◽

Ü Ugaste ◽

E Mellikov

Keyword(s):

Point Defects ◽

Extended Defects ◽

Sio2 System ◽

Defects And Impurities

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TEM Study of Defects in Laterally Overgrown GaN Layers

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300002891 ◽

1999 ◽

Vol 4 (S1) ◽

pp. 459-464 ◽

Cited By ~ 11

Author(s):

Z. Liliental-Weber ◽

M. Benamara ◽

W. Swider ◽

J. Washburn ◽

J. Park ◽

...

Keyword(s):

Electron Microscopy ◽

Point Defects ◽

Crystallographic Direction ◽

Initial Growth ◽

Lateral Growth ◽

Planar Defects ◽

Transmission Electron ◽

Defects And Impurities ◽

Two Sides ◽

Line Direction

Transmission electron microscopy was applied to study defects in laterally overgrown GaN layers, with initial growth on Al2O3 substrates followed by further growth over SiO2 masks. Dislocations found in the overgrown areas show changes in line direction. Most dislocations propagate along c-planes. In the overgrown material planar defects (faulted loops) are present on c-planes and their presence is most probably related to segregation of excess point defects and impurities present in this material. They appear to be initiated by the fast lateral growth. Some dislocations with screw orientation become helical resulting from climb motion.Formation of voids and also a high dislocation density was observed at the boundaries where two overgrowing fronts meet. Tilt and twist components were observed for these boundaries that were different for different overgrown strips grown in the same crystallographic direction suggesting that the GaN subgrain orientations on the two sides of a SiO2 mask are responsible for the final tilt and twist value.

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