Silicon Quantum Dots

download Silicon Quantum Dots

of 21

  • date post

    04-Apr-2018
  • Category

    Documents

  • view

    217
  • download

    0

Embed Size (px)

Transcript of Silicon Quantum Dots

  • 7/31/2019 Silicon Quantum Dots

    1/21

    Silicon Quantum Dots: Grownby Ion Implantation and

    annealing

    By

    Mary Coan

  • 7/31/2019 Silicon Quantum Dots

    2/21

    Outline

    History of Silicon quantum dots How they were made

    Properties of Silicon Quantum Dots grown

    by ion implantation and annealing Advantages/Disadvantages

    Different methods to grow Silicon

    Quantum Dots Which method is the best?

    Summary

  • 7/31/2019 Silicon Quantum Dots

    3/21

    History of Si QDs

    1960s: First quantum size effects were

    seen in semiconductor nanocrystals

    1970s: Louis Brus was working in Bell

    Labs researching colloidal synthesizes

    1980s: First semiconductor quantum dots

    were grown

    1990: First visible-photoluminescence

    seen from Si QDs

  • 7/31/2019 Silicon Quantum Dots

    4/21

    History of Si QDs

    1993: Silicon optoelectronic integratedcircuit is suggested

    1993 to present: Si Quantum dots have

    been extensively researched Different fabrication methods

    microwave plasma decomposition of SiH4

    laser breakdown of SiH4

    plasma-enhanced chemical vapor deposition

    high frequency discharge

    high dose ion implantation

  • 7/31/2019 Silicon Quantum Dots

    5/21

    Formation of Si QDs: Ion

    implantation and annealing

    T.S. Iwayama, T. Hama, D.E. Hole, I.W. Boyd, Vacuum 81, 179 (2006).

  • 7/31/2019 Silicon Quantum Dots

    6/21

    Properties of Si QDs

    Photoluminescence

    Peak energy and intensity

    Size ranges from 1 nm to over 10 nm indiameter

    Size distribution within host material

  • 7/31/2019 Silicon Quantum Dots

    7/21

    Photoluminescence

    C.W. White, J.D. Budai, S.P. Withrow, J.G. Zhu and S.J. Pennycock, IEEEConference Proceeding 824 (1996).

  • 7/31/2019 Silicon Quantum Dots

    8/21

    Photoluminescence

    T.S. Iwayama, T. Hama, D.E. Hole, I.W. Boyd, Vacuum 81, 179 (2006).

  • 7/31/2019 Silicon Quantum Dots

    9/21

    Photoluminescence

    T.S. Iwayama, T. Hama, D.E. Hole, I.W.Boyd, Vacuum 81, 179 (2006).

  • 7/31/2019 Silicon Quantum Dots

    10/21

    Suggested Mechanisms

    T.S. Iwayama, T. Hama, D.E. Hole, I.W. Boyd, Solid-State Electronics 45, 1487 (2001).

  • 7/31/2019 Silicon Quantum Dots

    11/21

    Suggested Mechanisms

    R. Krishnan, UR, (2005).

  • 7/31/2019 Silicon Quantum Dots

    12/21

    Range of Sizes

    Longer anneals = Larger Si QDs

    Ostwald Ripening

    T.S. Iwayama, T. Hama, D.E. Hole, I.W. Boyd, Vacuum 81, 179 (2006).

  • 7/31/2019 Silicon Quantum Dots

    13/21

    Size distribution within Host Material

    M.L. Brongersma, A. Polman, K.S. Min, H.A.Atwater, J. Appl. Phys. 86, 759 (1999).

  • 7/31/2019 Silicon Quantum Dots

    14/21

    Defects within Host

    C. J. Nicklaw, M. P. Pagey, S. T. Pantelides, D. M. Fleetwood, R. D. Schrimpf, K. F.

    Galloway, J. E. Wittig, B. M. Howard, E. Taw, W. H. McNeil, J. F. Conley, Jr., IEEE Trans.Nucl. Science 47, 2269 (2000).

  • 7/31/2019 Silicon Quantum Dots

    15/21

    Defects within Host

    C. J. Nicklaw, M. P. Pagey, S. T. Pantelides, D. M. Fleetwood, R. D. Schrimpf, K. F.

    Galloway, J. E. Wittig, B. M. Howard, E. Taw, W. H. McNeil, J. F. Conley, Jr., IEEE Trans.Nucl. Science 47, 2269 (2000).

  • 7/31/2019 Silicon Quantum Dots

    16/21

    Defects within Host

    C. J. Nicklaw, M. P. Pagey, S. T. Pantelides, D. M. Fleetwood, R. D. Schrimpf, K. F.

    Galloway, J. E. Wittig, B. M. Howard, E. Taw, W. H. McNeil, J. F. Conley, Jr., IEEE Trans.Nucl. Science 47, 2269 (2000).

  • 7/31/2019 Silicon Quantum Dots

    17/21

    Advantages/Disadvantages

    Advantages:

    Ease of integration into silicon based

    microelectronics (Dots and Process)

    Ability to control the PL intensity and peak

    energy

    Disadvantages:

    Large size distribution within host material

    Defects within host material

    Surface damage (QDs)

  • 7/31/2019 Silicon Quantum Dots

    18/21

    Other Fabrication Techniques

    Microwave Plasma Decomposition of

    Silane Gas

    Laser breakdown of Silane Gas

    Plasma Enhanced Chemical Vapor

    Deposition

    High Frequency Spark Discharge Colloidal

  • 7/31/2019 Silicon Quantum Dots

    19/21

    Which Method is Best?

    It depends on what you want to use the

    Silicon QDs for.

    If you want to make an optoelectical

    integrated circuit:

    Plasma Enhanced CVD

    Ion Implantation

    If you want some cool flourishing Si QDs:

    Colloidal

  • 7/31/2019 Silicon Quantum Dots

    20/21

    Summary

    Properties of Si QDs were discussed

    PL dependent on: Anneal time, temperature and process

    Ion dose Defects caused by Ion Implantation

    Quantum dot surface\host material Causing lower luminescence intensity

    A Large size distribution throughout the Host

    In the past this was a good technique nowit is outdated by PCVD

  • 7/31/2019 Silicon Quantum Dots

    21/21

    Questions ??