Boron Ted in Pre-Amorphised SI: Role of the A/C Interface

MRS Proceedings ◽

10.1557/proc-532-55 ◽

1998 ◽

Vol 532 ◽

Cited By ~ 2

Author(s):

D. Mathiot ◽

C. Bonafos ◽

M. OMRI ◽

D. Alquier ◽

A. Martinez ◽

...

Keyword(s):

Ostwald Ripening ◽

The Self ◽

Experimental Results ◽

Extended Defects ◽

Dopant Diffusion ◽

Boron Diffusion ◽

Nucleation Stage ◽

Diffusion Enhancement

ABSTRACTIn this paper we first review the main experimental results concerning boron diffusion in preamorphised silicon, focusing on the role played by the End Of Range defects. It is then shown that the application of the Ostwald ripening theory to the particular geometry of these defects permits to understand why and how they affect dopant diffusion. Contradictory experimental results can be reconciled if one considers that most of the diffusion enhancement occurs during the nucleation stage of the extended defects, and that the amorphous / crystalline interface is a perfect screen for the diffusion of the self-interstitials.

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The role of extended defects on transient boron diffusion in ion-implanted silicon

Materials Science and Engineering B ◽

10.1016/0921-5107(92)90001-p ◽

1992 ◽

Vol 12 (4) ◽

pp. 307-325 ◽

Cited By ~ 16

Author(s):

R.J. Schreutelkamp ◽

J.S. Custer ◽

V. Raineri ◽

W.X. Lu ◽

J.R. Liefting ◽

...

Keyword(s):

Extended Defects ◽

Boron Diffusion ◽

Ion Implanted

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A Physically Based Modeling of Boron TED in Amorphised Si

MRS Proceedings ◽

10.1557/proc-610-b10.4 ◽

2000 ◽

Vol 610 ◽

Author(s):

Evelyne Lampin ◽

Vincent Senez ◽

Alain Claveriel

Keyword(s):

Ostwald Ripening ◽

Physically Based Modeling ◽

Extended Defects ◽

Dislocation Loops ◽

Boron Diffusion ◽

Experimental Conditions ◽

Physically Based ◽

Free Interstitial ◽

Recombination Velocity ◽

Process Simulator

AbstractWe have developed a physically based modeling of TED of implanted boron in amorphised Si. The simulation starts with a supersaturation of Si free interstitials located below the amorphous/crystalline interface which, upon annealing, tend to diffuse out or to precipitate in the form of extended defects (clusters, {113}s, dislocation loops). The modeling of the nucleation and growth of these defects is divided into three distinct stages: the nucleation, the “pure growth” and the Ostwald ripening. This system can interact with a surface (characterized by a given recombination velocity for Si interstitials) only after the SPE regrowth is completed. Implementation of this model into a process simulator allows to describe the isothermal and isochronal evolutions of the sizes and of the densities of dislocation loops in agreement with TEM observations. Assuming that boron diffusion is caused by the concomitant time and space variations of the free interstitial supersaturation in the wafer, TED can be accurately predicted for a variety of experimental conditions.

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Strengths and Limitations of the Vacancy Engineering Approach for the Control of Dopant Diffusion and Activation in Silicon

MRS Proceedings ◽

10.1557/proc-1070-e01-02 ◽

2008 ◽

Vol 1070 ◽

Cited By ~ 5

Author(s):

Alain Claverie ◽

Fuccio Cristiano ◽

Mathieu Gavelle ◽

Fabrice Sévérac ◽

Frédéric Cayrel ◽

...

Keyword(s):

Ostwald Ripening ◽

Solubility Limit ◽

High Energy ◽

Dopant Diffusion ◽

Boron Diffusion ◽

Significant Control ◽

Alternative Approach ◽

Silicon Excess ◽

Ultra Shallow Junctions ◽

Activation Annealing

ABSTRACTThe fabrication of highly doped and ultra-shallow junctions in silicon is a very challenging problem for the materials scientist. The activation levels which are targeted are well beyond the solubility limit of current dopants in Si and, ideally, they should not diffuse during the activation annealing. In practice, the situation is even worse and when boron is implanted into silicon excess Si interstitial atoms are generated which enhance boron diffusion and favor the formation of Boron-Silicon Interstitials Clusters (BICs). An elegant approach to overcome these difficulties is to enrich the Si layers where boron will be implanted with vacancies before or during the activation annealing. Spectacular results have been recently brought to the community showing both a significant control over dopant diffusion and an increased activation of boron in such layers. In general, the enrichment of the Si layers with vacancies is obtained by Si+ implantation at high energy. We have recently developed an alternative approach in which the vacancies are injected from populations of empty voids undergoing Ostwald ripening during annealing. While different, the effects are also spectacular. The goal of this work is to establish a fair evaluation of these different approaches under technologically relevant conditions. The application domains of both techniques are discussed and future directions for their development/improvement are indicated.

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The Role of Vacancies and Interstitials in Transient Enhanced Diffusion of Arsenic Implanted into Silicon

MRS Proceedings ◽

10.1557/proc-469-315 ◽

1997 ◽

Vol 469 ◽

Cited By ~ 5

Author(s):

D. Venables ◽

V. Krishnamoorthy ◽

H.- J. Gossmann ◽

A. Lilak ◽

K. S. Jones ◽

...

Keyword(s):

Fermi Level ◽

Point Defect ◽

Boron Diffusion ◽

Direct Role ◽

Enhanced Diffusion ◽

Projected Range ◽

Transient Enhanced Diffusion ◽

Diffusion Enhancement ◽

Recombination Centers

ABSTRACTBoron and antimony doped superlattices (DSLs) were implanted with arsenic at 40 keV to doses of 2×1014 cm−2, 5×1015 cm−2 and 2×1016 cm−2. Increasing the arsenic dose above 5×1015 cm−2 resulted in a reduction in the extent of arsenic transient enhanced diffusion (TED) following annealing at 700°C, 16 hr. Concurrent with this reduction in TED was a reduction in the number of free interstitials beyond the end-of-range, as measured by the boron diffusion enhancement in the doped superlattices. No enhancement in antimony diffusivity was observed in this region, indicating that vacancies play no direct role in the diffusion of arsenic in this region, although an indirect role for vacancies as recombination centers for mobile interstitials is not precluded by these experiments. We conclude that interstitials dominate arsenic diffusion in the end-of-range region and beyond. Interpretation of the DSL data in the projected range region is complicated by Fermi level and segregation effects and no definitive conclusion can be reached about the point defect populations in this region.

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Fine structure and properties of defects in naturally occurring silicates and oxides

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175430 ◽

1990 ◽

Vol 48 (4) ◽

pp. 460-461

Author(s):

David R. Veblen

Keyword(s):

Chemical Reactions ◽

High Resolution Electron Microscopy ◽

Extended Defects ◽

Single Chain ◽

Naturally Occurring ◽

Resolution Electron ◽

Fine Structures ◽

Image Simulations ◽

Similar Crystal Structure

Extended defects and interfaces control many processes in rock-forming minerals, from chemical reactions to rock deformation. In many cases, it is not the average structure of a defect or interface that is most important, but rather the structure of defect terminations or offsets in an interface. One of the major thrusts of high-resolution electron microscopy in the earth sciences has been to identify the role of defect fine structures in reactions and to determine the structures of such features. This paper will review studies using HREM and image simulations to determine the structures of defects in silicate and oxide minerals and present several examples of the role of defects in mineral chemical reactions. In some cases, the geological occurrence can be used to constrain the diffusional properties of defects.The simplest reactions in minerals involve exsolution (precipitation) of one mineral from another with a similar crystal structure, and pyroxenes (single-chain silicates) provide a good example. Although conventional TEM studies have led to a basic understanding of this sort of phase separation in pyroxenes via spinodal decomposition or nucleation and growth, HREM has provided a much more detailed appreciation of the processes involved.

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