Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Characterization of the feature-size dependence in Ar/Cl2 chemically assisted ion beam etching of InP-based photonic crystal devices
KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.
KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.
KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.
CNRS, LPN.
Show others and affiliations
2007 (English)In: Journal of Vacuum Science & Technology B, ISSN 1071-1023, E-ISSN 1520-8567, Vol. 25, no 1, 1-10 p.Article in journal (Refereed) Published
Abstract [en]

The authors address feature-size dependence in Ar/Cl-2, chemically assisted ion beam etching (CAIBE) in the context of the fabrication of photonic crystal (PhC) structures. They systematically investigate the influence of various parameters such as hole diameter (115-600 nm), etch duration (10-60 min), and ion beam energy (300-600 eV) on PhC etching in InP with Ar/Cl-2, CAIBE. For a 60 min etching at an Ar-ion energy of 400 eV, the authors report an etch depth of 5 mu m for hole diameters d larger than 300 nm; the etch depth is in excess of 3 mu m for d larger than 200 nm. The evolution of roughness at the bottom of the etched holes and its dependence on hole size and etching conditions,is discussed. The physical mechanism of the observed feature-size dependent etching (FSDE) is then discussed and the effect of the process parameters is qualitatively understood using a model combining the effect of ion sputtering and surface chemical reactions. Finally, the effect of FSDE on the PhC optical properties is assessed by measuring the quality factor of one-dimensional Fabry-Perot PhC cavities. The measured quality factors show a clear trend with the etch depth: the cavity Q increases as the etch depth increases.

Place, publisher, year, edition, pages
2007. Vol. 25, no 1, 1-10 p.
Keyword [en]
WAVE-GUIDES; FABRICATION; GAAS; MODE; SEMICONDUCTOR; CHLORINE; CAVITY; RATIO; CL2
National Category
Physical Sciences
Identifiers
URN: urn:nbn:se:kth:diva-8375DOI: 10.1116/1.2402142ISI: 000244512400003Scopus ID: 2-s2.0-34047147995OAI: oai:DiVA.org:kth-8375DiVA: diva2:13680
Note
QC 20100707Available from: 2008-05-08 Created: 2008-05-08 Last updated: 2010-07-07Bibliographically approved
In thesis
1. InP-based photonic crystals: Processing, Material properties and Dispersion effects
Open this publication in new window or tab >>InP-based photonic crystals: Processing, Material properties and Dispersion effects
2008 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Photonic crystals (PhCs) are periodic dielectric structures that exhibit a photonic bandgap, i.e., a range of wavelength for which light propagation is forbidden. The special band structure related dispersion properties offer a realm of novel functionalities and interesting physical phenomena. PhCs have been manufactured using semiconductors and other material technologies. However, InP-based materials are the main choice for active devices at optical communication wavelengths. This thesis focuses on two-dimensional PhCs in the InP/GaInAsP/InP material system and addresses their fabrication technology and their physical properties covering both material issues and light propagation aspects.

Ar/Cl2 chemically assisted ion beam etching was used to etch the photonic crystals. The etching characteristics including feature size dependent etching phenomena were experimentally determined and the underlying etching mechanisms are explained. For the etched PhC holes, aspect ratios around 20 were achieved, with a maximum etch depth of 5 microns for a hole diameter of 300 nm. Optical losses in photonic crystal devices were addressed both in terms of vertical confinement and hole shape and depth. The work also demonstrated that dry etching has a major impact on the properties of the photonic crystal material. The surface Fermi level at the etched hole sidewalls was found to be pinned at 0.12 eV below the conduction band minimum. This is shown to have important consequences on carrier transport. It is also found that, for an InGaAsP quantum well, the surface recombination velocity increases (non-linearly) by more than one order of magnitude as the etch duration is increased, providing evidence for accumulation of sidewall damage. A model based on sputtering theory is developed to qualitatively explain the development of damage.

The physics of dispersive phenomena in PhC structures is investigated experimentally and theoretically. Negative refraction was experimentally demonstrated at optical wavelengths, and applied for light focusing. Fourier optics was used to experimentally explore the issue of coupling to Bloch modes inside the PhC slab and to experimentally determine the curvature of the band structure. Finally, dispersive phenomena were used in coupled-cavity waveguides to achieve a slow light regime with a group index of more than 180 and a group velocity dispersion up to 10^7 times that of a conventional fiber.

Place, publisher, year, edition, pages
Stockholm: KTH, 2008. xv, 115 p.
Series
Trita-ICT/MAP AVH, ISSN 1653-7610 ; 2008:7
Keyword
Photonic crystals, indium phosphide, photonic bandgap, Bloch modes, slow light, dispersion, coupled cavity waveguides, chemically assisted ion beam etching, lag effect, cavities, optical losses, carrier transport, carrier lifetimes, negative refraction, photonic bandstructure
National Category
Physical Sciences
Identifiers
urn:nbn:se:kth:diva-4734 (URN)978-91-7178-969-3 (ISBN)
Public defence
2008-05-30, N1, Electrum 3, Kista, 10:00
Opponent
Supervisors
Note
QC 20100712Available from: 2008-05-08 Created: 2008-05-08 Last updated: 2010-07-12Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Berrier, AudreyMulot, MikaëlAnand, Srinivasan
By organisation
Microelectronics and Applied Physics, MAP
In the same journal
Journal of Vacuum Science & Technology B
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 160 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf