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
Performance optimisation of epitaxially regrown 1.3-μm vertical-cavity surface-emitting lasers
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.
KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.ORCID iD: 0000-0002-9040-4740
2009 (English)In: IET Optoelectronics, ISSN 1751-8768, Vol. 3, no 2, 112-121 p.Article in journal (Refereed) Published
Abstract [en]

A number of GaAs-based long-wavelength, vertical-cavity, surface-emitting laser structures with optical and electrical confinement based on selective area epitaxy have been fabricated and evaluated. The influence on output power, threshold current, thermal stability and modal properties from design parameters such as bottom-distributed Bragg reflector (DBR) doping, cavity doping, dielectric top DBR design and carrier confinement barriers is evaluated. More than 7 mW of output power is emitted from multimode devices with a square active region size of 10 mm. Single-mode power from smaller devices is restricted to 1.5 mW because of a non-optimal cavity shape.

Place, publisher, year, edition, pages
2009. Vol. 3, no 2, 112-121 p.
Keyword [en]
VCSELS; OXIDATION; POWER; INP
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:kth:diva-8627DOI: 10.1049/iet-opt.2008.0037ISI: 000265259100007Scopus ID: 2-s2.0-63049130256OAI: oai:DiVA.org:kth-8627DiVA: diva2:13999
Note
QC 20100825. Uppdaterad från manuskript till artikel (20100825). Tidigare titel: Performance optimization of epitaxially regrown 1.3-μm VCSELsAvailable from: 2008-06-03 Created: 2008-06-03 Last updated: 2014-06-12Bibliographically approved
In thesis
1. Design and fabrication of long wavelength vertical cavity lasers on GaAs substrates
Open this publication in new window or tab >>Design and fabrication of long wavelength vertical cavity lasers on GaAs substrates
2008 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Vertical cavity surface emitting lasers (VCSELs) are today a commodity on the short wavelength laser market due to the ease with which they are manufactured. Much effort has in the last decade been directed towards making long wavelength VCSELs as successful in the marketplace. This has not been achieved due to the much more difficult fabrication technologies needed for realising high performance long wavelength VCSELs. At one point, GaInNAs quantum wells gain regions grown on GaAs substrates seemed to be the solution as it enabled all-epitaxial VCSELs that could make use of high contrast AlGaAs-based distributed Bragg reflectors (DBRs) as mirrors and lateral selective oxidation for optical and electrical confinement, thereby mimicking the successful design of short wavelength VCSELs. Although very good device results were achieved, reproducible and reliable epitaxial growth of GaInNAs quantum wells proved difficult and the technology has not made its way into high-volume production. Other approaches to the manufacturing and material problems have been to combine mature InP-based gain regions with high contrast AlGaAs-based DBRs by wafer fusion or with high contrast dielectric DBRs. Commonly, a patterned tunnel junction provides the electrical confinement in these VCSELs. Excellent performance has been achieved in this way but the fabrication process is difficult.

In this work, we have employed high strain InGaAs quantum wells along with large detuning between the gain peak and the emission wavelength to realize GaAs-based long wavelength VCSELs. All-epitaxial VCSELs with AlGaAs-based DBRs and lateral oxidation confinement were fabricated and evaluated. The efficiency of these VCSELs was limited due to the optical absorption in the doped DBRs. To improve the efficiency and manufacturability, two novel optical and electrical confinement schemes based on epitaxial regrowth of current blocking layers were developed. The first scheme is based on a single regrowth step and requires very precise processing. This scheme was therefore not developed beyond the first generation but single mode power of 0.3 mW at low temperature, -10ºC, was achieved. The second scheme is based on two epitaxial regrowth steps and does not require as precise processing. Several generations of this design were manufactured and resulted in record high power of 8 mW at low temperature, 5ºC, and more than 3 mW at high temperature, 85ºC. Single mode power was more modest with 1.5 mW at low temperature and 0.8 mW at high temperature, comparable to the performance of the single mode lateral oxidation confined VCSELs. The reason for the modest single mode power was found to be a non-optimal cavity shape after the second regrowth that leads to poor lateral overlap between the gain in the quantum wells and the intensity of the optical field.

Place, publisher, year, edition, pages
Stockholm: KTH, 2008. 79 p.
Series
Trita-ICT/MAP AVH, ISSN 1653-7610 ; 2008:10
Keyword
VCSEL, Selective Area Epitaxy, Epitaxial regrowth, Laser
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-4795 (URN)978-91-7178-990-7 (ISBN)
Public defence
2008-06-12, N2, Electrum 3, Isafjordsgatan 28 A/D, Kista, 10:00
Opponent
Supervisors
Note
QC 20100825Available from: 2008-06-03 Created: 2008-06-03 Last updated: 2010-08-25Bibliographically approved
2. Developments for Improved Performance Vertical-Cavity Surface Emitting Lasers
Open this publication in new window or tab >>Developments for Improved Performance Vertical-Cavity Surface Emitting Lasers
2014 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

The vertical-cavity surface-emitting laser (VCSEL) is a type of laser diode that emits light from the surface of the chip from which it is manufactured rather than from a cleaved edge as so far has been common for most telecommunication lasers. VCSEL’s low cost, high power efficiency and low power consumption properties make it a very attractive signal source for many applications such as fiber optical communication, optical interconnects, 3D sensing, absorption spectroscopy, laser printing, etc.

In this work, we have developed and evaluated new designs and technologies for extending the performance of VCSELs based on the GaAs material system. A novel scheme for single-mode emission from large size VCSELs, with active region size up to 10 μm, is proposed and discussed. Oxide-free designs of the VCSEL structure either based on an epitaxially regrown p-n-p layer or a buried tunnel junction (BTJ) for lateral current confinement are fabricated and characterized; the latter scheme yielding significant dynamic and static performance improvement as compared to epitaxially regrown design. In addition, the first room-temperature operation of a heterojunction bipolar transistor (HBT) 980nm VCSEL, a so-called transistor-VCSEL, is demonstrated. This novel three-terminal operational VCSEL is believed to have the potential for a ultrahigh modulation bandwidth due to altered carrier dynamics in the cavity region.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2014. 61 p.
Series
TRITA-ICT/MAP AVH, ISSN 1653-7610 ; 2014:11
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-146641 (URN)978-91-7595-164-5 (ISBN)
Presentation
2014-06-13, Sal/hall D, KTH-ICT, Isafjordgatan 39, Kista, 10:00 (English)
Opponent
Supervisors
Note

QC 20140612

Available from: 2014-06-12 Created: 2014-06-12 Last updated: 2014-06-13Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Hammar, Mattias

Search in DiVA

By author/editor
Marcks von Würtemberg, RickardYu, XingangBerggren, JesperHammar, Mattias
By organisation
Microelectronics and Applied Physics, MAP
Condensed Matter Physics

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 132 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