Optical Absorption Enhancement in Silicon Nanohole Arrays for Solar Photovoltaics

Click here to load reader

  • date post

    30-Dec-2015
  • Category

    Documents

  • view

    25
  • download

    0

Embed Size (px)

description

Optical Absorption Enhancement in Silicon Nanohole Arrays for Solar Photovoltaics. Sang Eon Han and Gang Chen* Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139. Reporter: Bo-Yu Huang Advisor: Peichen Yu - PowerPoint PPT Presentation

Transcript of Optical Absorption Enhancement in Silicon Nanohole Arrays for Solar Photovoltaics

  • **

    Optical Absorption Enhancement in SiliconNanohole Arrays for Solar Photovoltaics

    Reporter: Bo-Yu HuangAdvisor: Peichen YuGreen Phtonics Lab., National Chiao Tung University**Sang Eon Han and Gang Chen*Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

    NCTU IEO PHASOR

    NCTU IEO GPLab

    OutlineIntroductionNanorod arraysNanohole arrays

    Simulation & Discussion

    Summary

    NCTU IEO PHASOR

    NCTU IEO GPLab

    IntroductionPoor infrared absorption of crystalline silicon (indirect band gap)

    200-300 m c-Si active layers that absorb light efficientlyThis thickness accounts for 40% of the total cost

    An effective technique for light trapping in thin active layers needs to be developed

    NCTU IEO PHASOR

    NCTU IEO GPLab

    IntroductionNanorod arraysConstruct a p-n or a p-i-n junction in the radial direction of each nanorodShorten the carrier diffusion lengthAnti-reflection

    NCTU IEO PHASOR

    NCTU IEO GPLab

    IntroductionNanohole arraysWe find that nanohole arrays are comparable to or even better than nanorod arrays in terms of light absorption.

    NCTU IEO PHASOR

    NCTU IEO GPLab

    *IntroductionSilicon nanohole arrays exhibit better absorption and mechanical robustnessApplied physics letter, 96, 181903 (2010)Nano letters,10, 1082 (2010)JACS, 132, 6872 (2010)

    NCTU IEO PHASOR

    NCTU IEO GPLab

    Simulation & Discussion

    For rod:Filling fraction=

    NCTU IEO PHASOR

    NCTU IEO GPLab

    Simulation & DiscussionAbsorption is higher for the nanohole array when is less than approximately 750 nm

    NCTU IEO PHASOR

    NCTU IEO GPLab

    Simulation & Discussion thickness is 2.33 m

    NCTU IEO PHASOR

    NCTU IEO GPLab

    SummaryWe have presented the optical properties of c-Si nanohole array structures and found that their absorption is better than nanorod arrays.

    Nanohole array structure requiring one-twelfth the c-Si mass and one-sixth the thickness of a standard 300 m Si wafer.

    NCTU IEO PHASOR

    NCTU IEO GPLab

    Thanks for your attention!!**

    NCTU IEO PHASOR

    NCTU IEO GPLab

    backup**

    NCTU IEO PHASOR

    Here, we are intersting in silicon nanohole. BecauseAt 2010, some researches have shown that silicon nanohole behave better light absorption than film or nanowire.On the other hand, nanowire or nanohole solar cell with radial pn junction could shorten the diffusion length. In fact, beside the better absorption, nanohole have stronger mechanical robustness. Make it easier to fabricate and have more applications.*