Extended Defects Formation in Nanosecond Laser-Annealed Ion Implanted Silicon

AbstractWe present an extensive study of the thermal evolution of the extended defects found in ion implanted Si as a function of annealing conditions. We will first review their structure and energetics and show that the defect kinetics can be described by an Ostwald ripening process whereby the defects exchange Si atoms and evolve in size and type to minimise their formation energy. Finally, we will present a physically based model to predict the evolution of extrinsic defects during annealing through the calculation of defect densities, size distributions, number of clustered interstitials and free-interstitial supersaturation. We will show some successful applications of our model to a variety of experimental conditions and give an example of its predictive capabilities at ultra low implantation energies.

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The Behavior of Ion-Implanted Hydrogen in Gallium Nitride

MRS Proceedings ◽

10.1557/proc-537-g5.8 ◽

1998 ◽

Vol 537 ◽

Author(s):

S. M. Myers ◽

T.J. Headley ◽

C.R. Hills ◽

J. Han ◽

G.A. Petersen ◽

...

Keyword(s):

Bound States ◽

Bubble Formation ◽

Extended Defects ◽

Wurtzite Phase ◽

Ion Channeling ◽

Transmission Electron ◽

Microstructural Effects ◽

Formation And Evolution ◽

Ion Implanted

AbstractHydrogen was ion-implanted into wurtzite-phase GaN, and its transport, bound states, and microstructural effects during annealing up to 980°C were investigated by nuclear-reaction profiling, ion-channeling analysis, transmission electron microscopy, and infrared (IR) vibrational spectroscopy. At implanted concentrations vl at.%, faceted H 2 bubbles formed, enabling identification of energetically preferred surfaces, examination of passivating N-H states on these surfaces, and determination of the diffusivity-solubility product of the H. Additionally, the formation and evolution of point and extended defects arising from implantation and bubble formation were characterized. At implanted H concentrations ^0.1 at.%, bubble formation was not observed, and ion-channeling analysis indicated a defect-related H site located within the [0001] channel.

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BIC Formation and Boron Diffusion in Relaxed Si0.8Ge0.2

MRS Proceedings ◽

10.1557/proc-810-c7.4 ◽

2004 ◽

Vol 810 ◽

Author(s):

R. T. Crosby ◽

L. Radic ◽

K. S. Jones ◽

M. E. Law ◽

P.E. Thompson ◽

...

Keyword(s):

Surface Region ◽

Extended Defects ◽

Defect Structures ◽

Boron Diffusion ◽

Plan View ◽

Near Surface ◽

Transmission Electron ◽

Secondary Ion ◽

Ion Implanted

ABSTRACTThe relationships between Boron Interstitial Cluster (BIC) evolution and boron diffusion in relaxed Si0.8Ge0.2 have been investigated. Structures were grown by Molecular Beam Epitaxy (MBE) with surface boron wells of variant composition extending 0.25 [.proportional]m into the substrate, as well as boron marker layers positioned 0.50 [.proportional]m below the surface. The boron well concentrations are as follows: 0, 7.5×1018, 1.5×1019, and 5.0×1019 atoms/cm3. The boron marker layers are approximately 3 nm wide and have a peak concentration of 5×1018 atoms/cm3. Samples were ion implanted with 60 keV Si+ at a dose of 1×1014 atoms/cm2 and subsequently annealed at 675°C and 750°C for various times. Plan-view Transmission Electron Microscopy (PTEM) was used to monitor the agglomeration of injected silicon interstitials and the evolution of extended defects in the near surface region. Secondary Ion Mass Spectroscopy (SIMS) concentration profiles facilitated the characterization of boron diffusion behaviors during annealing. Interstitial supersaturation conditions and the resultant defect structures of ion implanted relaxed Si0.8Ge0.2 in both the presence and absence of boron have been characterized.

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A Critical Regime for Amorphization of Ion Implanted Silicon

MRS Proceedings ◽

10.1557/proc-316-259 ◽

1993 ◽

Vol 316 ◽

Cited By ~ 12

Author(s):

R. D. Goldberg ◽

J. S. Williams ◽

R. G. Elliman

Keyword(s):

Damage Accumulation ◽

Anomalous Behaviour ◽

Critical Regime ◽

Extended Defects ◽

Complex Defect ◽

Defect Annealing ◽

Defect Accumulation ◽

Residual Damage ◽

Ion Species ◽

Ion Implanted

ABSTRACTA critical regime has been identified for ion implanted silicon where only slight changes in temperature can dramatically affect the levels of residual damage. In this regime decreases of only 5° C are sufficient to induce a crystalline-to-amorphous transformation in material which only exhibited the build-up of extended defects at higher temperatures. Traditional models of damage accumulation and amorphization have proven inapplicable to this regime which exists whenever dynamic defect annealing and damage production are closely balanced. Irradiating ion flux, mass and fluence have all been shown to influence the temperature— which varies over a range of 300° C for ion species ranging from C to Xe—at which the anomalous behaviour occurs. The influence of ion fluence suggests that complex defect accumulation plays an important role in amorphization. Results are presented which further suggest that the process is nucleation limited in this critical regime.

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