Capture of vacancies by extrinsic dislocation loops in silicon

1998 ◽  
Vol 72 (1) ◽  
pp. 67-69 ◽  
Author(s):  
S. B. Herner ◽  
H.-J. Gossmann ◽  
F. H. Baumann ◽  
G. H. Gilmer ◽  
D. C. Jacobson ◽  
...  
Keyword(s):  
Dislocation Loops ◽  
Extrinsic Dislocation

Defects and Diffusion in Si+ Implanted GaAs

1993 ◽  
Vol 300 ◽  
Author(s):  
K.S. Jones ◽  
H.G. Robinson ◽  
T.E. Haynes ◽  
M.D. Deal ◽  
C.C. Lee ◽  
...  
Keyword(s):  
Dislocation Loop ◽  
Vacancy Concentration ◽  
Total Concentration ◽  
Time Interval ◽  
Type I ◽  
Extended Defects ◽  
Dislocation Loops ◽  
Extrinsic Dislocation ◽  
Area Of Concern ◽  
And Diffusion

ABSTRACTThe effect of extended defects on the diffusion of ion implanted species is an area of concern in the development of process simulators for GaAs. This study explores the effect of type I extended defects including voids and dislocation loops on the diffusion of Si implanted into GaAs. <100> Semi-insulating GaAs wafers were implanted with 1 × 1014/cm2 Si+ at implant temperatures between -51°C and 80°C and at energies ranging from 20 keV to 200 keV. SIMS results show that the diffusivity of Si decreases with both increasing implant temperature and increasing implant energy. At the same time extrinsic dislocation loop concentrations also increased. For the implant conditions studied, no voids were observed. The diffusion results can only be reconciled with the TEM results if the dislocation loops are behaving in a reactive rather than proactive manner. In other words, the changes in vacancy concentration that are affecting the diffusivity are also affecting the loop concentration. This model is supported by evidence that Si diffusivity is enhanced over the same time interval the dislocation loops are dissolving which is consistent with the loops having a reactive role. It remains unclear whether the existence of loops significantly affects the total concentration of vacancies and thus diffusion by acting as a competing sink.

Transient Enhanced Diffusion of Dopants in Preamorphised Si Layers

1996 ◽  
Vol 438 ◽  
Author(s):  
A. Claverie ◽  
C. Bonafos ◽  
M. Omri ◽  
B. De Mauduit ◽  
G. Ben Assayag ◽  
...  
Keyword(s):  
Ostwald Ripening ◽  
Dislocation Loops ◽  
Boron Diffusion ◽  
Enhanced Diffusion ◽  
Transient Enhanced Diffusion ◽  
Interstitial Atoms ◽  
Extrinsic Dislocation ◽  
The Mean ◽  
Boron Diffusivity ◽  
Shed Light

AbstractTransient Enhanced Diffusion (TED) of dopants in Si is the consequence of the evolution, upon annealing, of a large supersaturation of Si self-interstitial atoms left after ion bombardment. In the case of amorphizing implants, this supersaturation is located just beneath the c/a interface and evolves through the nucleation and growth of End-Of-Range (EOR) defects.For this reason, we discuss here the relation between TED and EOR defects. Modelling of the behavior of these defects upon annealing allows one to understand why and how they affect dopant diffusion. This is possible through the development of the Ostwald ripening theory applied to extrinsic dislocation loops. This theory is shown to be readily able to quantitatively describe the evolution of the defect population (density, size) upon annealing and gives access to the variations of the mean supersaturation of Si self-interstitial atoms between the loops and responsible for TED. This initial supersaturation is, before annealing, at least 5 decades larger than the equilibrium value and exponentially decays with time upon annealing with activation energies that are the same than the ones observed for TED. It is shown that this time decay is precisely at the origin of the transient enhancement of boron diffusivity through the interstitial component of boron diffusion. Side experiments shed light on the effect of the proximity of a free surface on the thermal behavior of EOR defects and allow us to quantitatively describe the space and time evolutions of boron diffusivity upon annealing of preamorphised Si layers.

Enhanced Dissolution Of Extrinsic Dislocation Loops In Silicon Annealed In NH3

1996 ◽  
Vol 442 ◽  
Author(s):  
S. B. Herner ◽  
V. Krishnamoorthy ◽  
K. S. Jones ◽  
T. K. Mogi ◽  
H.-J. Gossmann
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Marked Decrease ◽  
Dislocation Loops ◽  
Enhanced Dissolution ◽  
Transmission Electron ◽  
Extrinsic Dislocation ◽  
Good Agreement

AbstractThe behavior of extrinsic dislocation loops in silicon was investigated by transmission electron microscopy. Loops were formed by an amorphizing implant and recrystallization anneal of Si wafers. Wafers were further annealed in either Ar or NH3. Wafers annealed in NH3 formed a thin (∼4 nm) SiNx film. The loops in samples in Ar showed a constant net number of interstitials bound by the loops, while those in samples annealed in NH3 showed a marked decrease. The results are explained by a supersaturation of vacancies recombining with the interstitials in loops. By integrating the measured difference between interstitials bound by the loops in samples annealed in Ar vs. NH3 over the distance from the surface to the loop layer, an estimate for the relative vacancy supersaturation is extracted. Comparison with estimates of vacancy supersaturations with nitridation from the change in Sb diffusivity show good agreement between the two methods.

Defect Structures Generated by Buried Amorphous Layer Regrowth in Arsenic Implanted Silicon

1986 ◽  
Vol 71 ◽  
Author(s):  
Kevin S. Jones ◽  
S. Prussin
Keyword(s):  
Ion Beam ◽  
Amorphous Layer ◽  
High Energy ◽  
Dislocation Loops ◽  
Furnace Annealing ◽  
Cross Sectional ◽  
Plan View ◽  
Extrinsic Dislocation ◽  
Shear Type ◽  
Type Dislocation

AbstractPlan-view and 90° cross-sectional TEM examination was used to investigate the correlation between the type of amorphous layer produced and the resulting defect structure observed upon annealing. Both <100> and <111> Si wafers were ion implanted with high energy (190 keV) arsenic over a range of doses(1 × 1015/cm2 to 5 × 1015/cm2). A Wayflow endstation was used allowing ion beam induced epitaxial crystallization (IBIEC)[8] or dynamic annealing of the sample to occur. Implanted <111> Si is shown to form a continuous amorphous layer up to the surface, while <100> implanted Si forms a buried amorphous layer. The regrowth of the buried x-layer by furnace annealing is shown to be responsible for the formation of shear type dislocation loops at the interface where the two x/c regrowth fronts meet (catagory IV defects).[7] However if the buried layer is regrown by dynamic annealing a different structure results.In addition to using <111> wafers, other parameter changes which resulted in the formation of surface amorphous layers included decreasing the implant energy from 190 keV to 100 keV, or implanting the wafer at 77K instead of using the Wayflow endstation. Regrowth of the surface amorphous layers produced by these changes did not result in the formation of shear type dislocation loops. Further annealing of the 100 keV Wayflow implant and the 190 keV 77K implant at 900°C for 30 minutes resulted in the formation of small prismatic extrinsic dislocation loops beneath the location of the original amorphous/crystalline interface (catagory II defects).[71]

Impurity induced layer disordering of Si implanted AlxGa1−xAs‐GaAs quantum‐well heterostructures: Layer disordering via diffusion from extrinsic dislocation loops

1987 ◽  
Vol 61 (4) ◽  
pp. 1329-1334 ◽  
Author(s):  
L. J. Guido ◽  
K. C. Hsieh ◽  
N. Holonyak ◽  
R. W. Kaliski ◽  
V. Eu ◽  
...  
Keyword(s):  
Quantum Well ◽  
Dislocation Loops ◽  
Extrinsic Dislocation

Extended Defects in Fe-Implanted InP After Thermal Annealing

1993 ◽  
Vol 316 ◽  
Author(s):  
C. Frigeri ◽  
C. Bocchi ◽  
A. Carnera ◽  
A. Gasparotto ◽  
N. Gambacorti ◽  
...  
Keyword(s):  
Thermal Annealing ◽  
Stacking Fault ◽  
Extended Defects ◽  
Dislocation Loops ◽  
Near Surface ◽  
Sample Stacking ◽  
Stacking Fault Tetrahedra ◽  
Crystalline Substrate ◽  
Extrinsic Dislocation ◽  
Recrystallization Front

ABSTRACTThe recovery of the implant-induced damage and the defects present after thermal annealing at 650 °C in Fe-implanted InP have been investigated by TEM, RBS and X-ray diffractometry as a function of the annealing time that was varied betweeen 0.5 and 2 h. The near-surface damaged layer was removed only for annealing times ≥ 1.5 h. The annealed samples contained stacking fault tetrahedra of vacancy type, extrinsic dislocation loops and microdefects. These extended defects were mostly localized in a band corresponding to the region of transition between amorphous top layer and crystalline substrate as was detected in the as-implanted sample. Stacking fault tetrahedra and loops have also been observed before and beyond this band, respectively. Such defects could be due to either shear strains at the recrystallization front or implant-induced point defects.

Anomalous Weak Beam Contrast from Extrinsic Stacking Faults

1981 ◽  
Vol 39 ◽  
pp. 242-243
Author(s):  
M.P. Shaw ◽  
P.G. Self
Keyword(s):  
Displacement Vector ◽  
Stacking Faults ◽  
Nickel Base Superalloy ◽  
Bright Field Image ◽  
Dislocation Loops ◽  
Fringe Contrast ◽  
Weak Beam ◽  
Image Width ◽  
Extrinsic Dislocation ◽  
Nickel Base

This paper concerns observations of anomalous fault contrast arising from weak beam images of extrinsic faulted dislocation loops. Weak beam images are of considerable use when examining lattice defects due to the reduced image width associated with dislocations and the fine detail revealed in the fringe contrast from stacking faults. The observations described here arose from a study of interstitial (extrinsic) dislocation loops produced by radiation damage in a commercial nickel base superalloy, Nimonic PE16(1).Figure 1 shows a bright field image revealing faulted loops on all four {111} planes of the f.c.c. structure. Complementary images taken in a variety of different two beam diffracting conditions showed the faulted loops to be <111> interstitial faults surrounded by <111> pure edge (Frank) partial dislocations. When images were taken under weak beam conditions, contrast from the stacking faults was found to be critically dependent on the sign of g.R (where g is the diffracting vector and R the displacement vector of the fault).

Dopant Redistribution During Silicide Formation

1985 ◽  
Vol 54 ◽  
Author(s):  
I. Ohdomari ◽  
K. Konuma ◽  
M. Takano ◽  
T. Chikyow ◽  
H. Kawarada ◽  
...  
Keyword(s):  
Solubility Limit ◽  
Good Evidence ◽  
Dislocation Loops ◽  
Enhanced Diffusion ◽  
Si Substrates ◽  
Vacancy Generation ◽  
Lower Solubility ◽  
Before And After ◽  
Extrinsic Dislocation ◽  
Dopant Redistribution

ABSTRACTAfter the review of dopant redistribution phenomena observed during formation of near noble metal suicides, we describe the results of our recent experiments to get a better understanding of a mechanism of the dopant redistribution phenomenon in Si substrates. The key factors to understand the dopant redistribution are dopant segregation at the suicide/ Si interface due to lower solubility limit of dopants in suicides, enhanced diffusion of dopants into the Si substrate at much lower temperatures than the ordinary thermal diffusion, and electrical activation of the redistributed dopants. The results of As and carrier concentration measurements before and after Pd2Si formation to make clear the third factor show that the electrical activity of the redistributed As atoms in Si is strongly dependent on the initial activity before Pd2Si formation which is controlled by the temperature for the pre-annealing of As implanted Si.Shrinkage of extrinsic dislocation loops introduced by As implantation and subsequent annealing have been observed after Pd2Si formation, which is a good evidence of vacancy generation during Pd2Si formation. The role of the vacancies and interstitials on the second factor, the enhanced diffusion, has also been discussed. Finally we list a few issues to be answered in future by more detailed works in order to get a complete understanding of the redistribution phenomenon.

Dislocation Nucleation, Growth and Suppression During Cw Laser Annealing of Silicon

1980 ◽  
Vol 1 ◽  
Author(s):  
G.A. Rozgonyi ◽  
H. Baumgart ◽  
F. Phillipp
Keyword(s):  
Laser Annealing ◽  
Laser Cavity ◽  
Pulse Mode ◽  
Dislocation Nucleation ◽  
Dislocation Loops ◽  
Large Area ◽  
Cw Laser ◽  
Transmission Electron ◽  
Extrinsic Dislocation ◽  
Free Material

ABSTRACTOptical, X-ray and transmission electron microscopy plus preferential chemical etching have been used to examine the dislocations and lattice strain introduced during cw laser annealing of silicon. In addition to a substrate scanning mode we operate our cw Ar-ion laser in a “pulse” mode by using an electronically activated shutter located within the laser cavity. This permits accurate measurements to be made on isolated spots or large area scans with a dislocation density that can be deliberately varied. In particular we discuss surface slip traces, their component dislocations and resulting lattice strains, as well as submicron extrinsic dislocation loops which result from the condensation of ion-implantation produced interstitial silicon. Recommendations are presented for producing defect and strain-free material, as well as samples with specific densities of dislocations.

Defect Mechanisms in Degradation of Long Wavelength (1.30–1.55 Micron) Laser Diodes

1990 ◽  
Vol 184 ◽  
Author(s):  
S. N. G. Chu
Keyword(s):  
Active Region ◽  
Laser Diodes ◽  
Normal Operation ◽  
Nonradiative Recombination ◽  
Dislocation Loops ◽  
Dark Line ◽  
Long Wavelength ◽  
Structural Deterioration ◽  
Extrinsic Dislocation ◽  
Buried Heterostructure

ABSTRACTOptical degradation of long wavelength (1.30–1.55 micron) laser diodes during normal operation or accelerated aging test caused by lattice structural deterioration of the active region materials and mirror facet damage were investigated in detail. Extrinsic dislocation loops of 1/2<100>{010) types were observed in gradually degraded channeled-substrate-buried-heterostructure (CSBH) lasers. These dislocation loops, originated at the sidewall interfaces outside the active region, grew into the active region in the direction of minority carrier injection. A great enhancement of the loops' growth rate was observed after they entered the active region, indicating a nonradiative recombination enhanced defect reaction under the strong optical field. Furthermore, the <100> oriented extrinsic dislocation loops were confirmed to be dark-line-defects (DLDs). On the other hand, strong nonradiative recombination centers, created by mirror facet damage, or pre-existed internally inside the cavity, resulted localized melting on the {111} planes. The propagation of the localized melt-patch along the laser beam direction created a wormlike defect along the laser cavity, which degraded the laser device catastrophically. Various types of grown-in defects for CSBH and etched-mesa-buried-heterostructure (EMBH) laser devices are described and their effects on the device performance are demonstrated.

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