Migration energies of point defects during electron irradiation of hydrogenated Si crystals

2002 ◽  
Vol 66 (15) ◽  
Author(s):  
M. Suezawa ◽  
Y. Takada ◽  
T. Tamano ◽  
R. Taniguchi ◽  
F. Hori ◽  
...  
Keyword(s):  
Point Defects ◽  
Electron Irradiation

Negative-U Properties for Point Defects in Silicon

1980 ◽  
Vol 2 ◽  
Author(s):  
G. D. Watkins
Keyword(s):  
Experimental Evidence ◽  
Point Defects ◽  
Electron Irradiation ◽  
Correlation Energy ◽  
Energy Levels ◽  
Unusual Property ◽  
Simple Point ◽  
Normal Order ◽  
Defect Energy ◽  
Lattice Vacancy

ABSTRACTA defect has negative-U properties if it can trap two electrons (or holes) with the second bound more strongly than the first. It is as if there were a net attraction between the two carriers (negative Hubbard correlation energy U) at the defect, and the defect energy levels in the gap are therefore inverted from their normal order. Experimental evidence is presented that interstitial boron and the lattice vacancy, both common simple point defects produced by electron irradiation of silicon, have this unusual property. These defects represent the first and only concrete examples of negative-U centers in any material and serve as models for an understanding of the phenomenon.

The Effect of Simultaneous Electron and Kr+ Irradiation on Amorphization of CuTi

1988 ◽  
Vol 128 ◽  
Author(s):  
J. Koike ◽  
P. R. Okamoto ◽  
L. E. Rehn ◽  
M. Meshii
Keyword(s):  
Dose Rate ◽  
Point Defects ◽  
Electron Irradiation ◽  
Irradiation Temperature ◽  
Additive Effect ◽  
Retardation Effect ◽  
Displacement Cascades ◽  
Simultaneous Irradiation ◽  
Relative Electron

ABSTRACTCuTi was irradiated with 1-MeV electrons and Kr+ ions simultaneously at temperatures from 10 to 423 K. Retardation of Kr+-induced amorphization was observed with simultaneous electron irradiation at 295 and 423 K. The retardation effect increased with increasing irradiation temperature and relative electron-to-Kr dose rate. In contrast, simultaneous irradiation below 100 K showed an additive effect of electron- and Kr+-induced amorphization. The results can be explained by the mobility point defects introduced by electron irradiation interacting with Kr+-induced displacement cascades.

Primary Defects in n-Type Irradiated Germanium: A First-Principles Investigation

2007 ◽  
Vol 131-133 ◽  
pp. 253-258 ◽  
Author(s):  
A. Carvalho ◽  
R. Jones ◽  
C. Janke ◽  
Sven Öberg ◽  
Patrick R. Briddon
Keyword(s):  
Low Temperature ◽  
Point Defects ◽  
Electron Irradiation ◽  
First Principles ◽  
Low Temperatures ◽  
Damage Evolution ◽  
Room Temperature ◽  
Temperature Electron ◽  
Conductivity Loss

The properties of point defects introduced by low temperature electron irradiation of germanium are investigated by first-principles modeling. Close Frenkel pairs, including the metastable fourfold coordinated defect, are modelled and their stability is discussed. It is found that damage evolution upon annealing below room temperature can be consistently explained with the formation of correlated interstitial-vacancy pairs if the charge-dependent properties of the vacancy and self-interstitial are taken into account. We propose that Frenkel pairs can trap up to two electrons and are responsible for conductivity loss in n-type Ge at low temperatures.

Flux Pinning Defects Induced by Electron Irradiation in Y1Ba2Cu3O7–8 Single Crystals

1992 ◽  
Vol 275 ◽  
Author(s):  
J. Giapintzakis ◽  
M. A. Kirk ◽  
W. C. Lee ◽  
J. P. Rice ◽  
D. M. Ginsberg ◽  
...  
Keyword(s):  
Single Crystals ◽  
Electron Energy ◽  
Point Defects ◽  
Electron Irradiation ◽  
Flux Pinning ◽  
Small Clusters

ABSTRACTSingle crystals of R1Ba2Cu3O7–8, (R=Y, Eu and Gd), have been irradiated with 0.4–1.0 MeV electrons in directions near the c-axis. An incident threshold electron energy for producing flux pinning defects has been found. In-situ TME studies found no visible defects induced by electron irradiation. This means that point defects or small clusters ( ≤ 20 Å) are responsible for the extra pinning. A consistent interpretation of the data suggests that the most likely pinning defect is the displacement of a Cu atom from the CuO2 planes.

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