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矽核光纖的製備與光學特性量測Silicon cored optical fibers

– fabrication and optical characterization

報告人：王倫 教授lon@ntu.edu.tw

2013-07-12

Acknowledgement• Coworkers: Yi-Chuan Tseng, Yan-Bo Huang Prof. Hsuen-Li Chen (Department of Material Science and Engineering)• Monthly discussion with the joint team members from Dr. Ching-Fuh Lin, Dr. Wing-Kit Choi and Dr. Chao-Hsin Wu. • This work is supported by International Collaboration

Project with Peking University (Grant No. NTU-ICRP-102R7558)

• .

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Outline Motivation and Prior Arts Design and Fabrication Experiment Results Discussion Summary

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• Optical fibers are silica based for communication/sensing• Pros and Cons

• Semiconductor devices -- Si based for electronics, III-V for light sources• Pros and Cons

• Semiconductor fibers ??• Many unknowns with expected pros and cons

• Potential Applications• mid-Infrared• Nonlinear• Silicon photonics• Sensing

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Motivation

Sand – abundant supply for making glass fibers and Si chips, a blessing from Heaven to whom we should be grateful.

Research Groups Worldwide• Southampton University• Clemson University• Pen. State University

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Properties of Semiconductor Fibers• Optics

Size: a few microns depending on transmission or sensingLow transmission loss

Crystalline, smooth interface or surface• Doping for light sources

• Rare earth elements

• Electronics Size: microwire to nanowireGood conductivity

Crystalline better than poly and amorphous Doping for n- and p-type

• E-O integration: 22nm node and below, placement, etc.

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Prior Arts

7Pier J. A. Sazio et al, Southampton University, Science Vol. 311 No. 1583 (2006)

fabricated by using HPCVD

carrier mobility 1.05 cm2/Vsvs.

typical Si FET 10^4-10^5 cm2/Vs

11mm long, dia. 100um, core 5um relatively easy in control on crystalline direction, roughness and diffusion. loss 3dB/cm

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P. J. A. Sazio et al,Southampton university, OE Vol. 20 No.4 (2012)

John Ballato et al, Clemson university, OE Vol. 16 No.23 (2008)

fabricated by using CVDfabricated by using molten core method

Prior Arts

a few meter long, loss 5~7dB/cm

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P. J. A. Sazio et al, Southampton university, Nature photonics, Vol. 6 No.174 (2012)

Prior Arts

amorphous p-n junction

Toward useful junction based devices

OE conversion with a pulsed laser

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JLT Vol. 27 No.15 (2009)

pure SiO2 micro fiber

Well, Our Prior Arts

Uniqueness: several meters long with below nm surface roughness

Using conventional SMF as preform

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Micro Coil Rings

1548.1 1548.2 1548.3 1548.4 1548.5 1548.6 1548.7 1548.8 1548.9 1549-3

-2.5

-2

-1.5

-1

-0.5

0

Wavelength (nm)

Tran

smis

sion

(dB

)

FSR = 270pm

Resolution: 5pm

Spectrum of 2-ring Coil

A typical photograph of an MCR whose gaps between adjacent rings are controlled within 1.5 μm.

Experiment Resultsoptical microscope images

ca. Cross section of Si cored

fiberb. Lateral view of Si cored

fiberc. Lateral view of silicon

core

Visual inspection

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Results and Discussion crystalline characterization

Chil-Chyuan Kuo, J. Russ. Laser Res., vol. 32, pp. 12 (2011)

B.L. Boyce et al., Acta Materialia, vol. 58, pp. 439 (2010)

Boundaries can be observed for a- and poly-Si when FE-SEM is used.

P. Hashemi et al, University of Tehran, Conference of Microelectronics, pp. 326 (2005)

Results and Discussion Raman characterization –

to know possible causes for crystalline

Summary• Long Si-cored silica-clad fibers were made.• Their propagation losses were measured, and

crystalline properties characterized.

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Thanks for your attention!• Questions?• Dreams?

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