kth.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • 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
Silicon photonic MEMS building blocks for low-power programmable circuits
KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.ORCID iD: 0000-0002-7339-6662
2022 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Silicon photonics, or the confinement and control of light in integrated silicon waveguides, has rapidly grown from research labs to high-end chips for telecommunications. With the associated improvements in waveguide performance, the technology is promising for a wide range of new applications, from computing to sensing. However, current chip implementations of such applications are limited in scale. The available actuators used to control the circuits do not have the performance needed as building blocks for large circuits requiring thousands of actuators.

Today’s silicon photonic circuits rely mainly on heaters and the thermo-optic effect for actuation. It enables the monolithic integration of reconfigurable building blocks in silicon photonic foundries with low optical losses and relatively short optical lengths. However, such heater-based building blocks consume over 1mW per device. Opto-electronic actuators are also available in silicon photonic foundries for high-speed modulation but are lossy and long.

Micromechanical actuators for silicon photonics could provide the missing technology for scaling photonic circuits. Silicon is a material with excellent mechanical properties, and MEMS actuators can therefore be designed on the same layers used for waveguides. Electrostatic MEMS actuators consume very low power (<1nW static leakage per device), can achieve optical losses on par with state-of-the-art thermo-optic devices, within shorter optical lengths, and have response times in the μs range. However, such actuators require the partial suspension of silicon structures for movement, which is not currently available in silicon photonic foundries and presents additional challenges for commercial packaging.

This thesis aims to bring large-scale photonic circuits closer to reality by integrating low-power and scalable silicon photonic MEMSactuators in a silicon photonics foundry platform. MEMS-based building blocks with scalable optical performance were developed and included in photonic circuits. The devices and circuits were implemented on a silicon photonics foundry platform (IMEC’s iSiPP50G)with a few foundry-compatible post-processing steps. Finally, a solution for wafer-level sealing of the MEMS actuators was developed, compatible with subsequent packaging and enhancing the mechanical performance of the devices.

Abstract [sv]

Kiselfotonik, eller ingränsningen och kontrollerandet av ljus i integrerade optiska vågledare av kisel, has vuxit fram snabbt från labbmiljö till högpresterande chip för telekommunikation. Med den samtida förbättringen i vågledarprestanda är den här teknologin lovande för ett brett spektra av nya applikationer, från specialiserad datorberäkning till sensorer. Nuvarande implementeringar av den här tekniken i chip är dock begränsad i skala. De tillgängliga byggstenarna som användas för att kontrollera kretsarna är inte rillräckligt bra för att användas upprepade gånger i stora kretsar.

Dagens aktiva byggstenar i kiselfotonik är beroende av uppvärmning och den termo-optiska effekten för aktuering. Den möjliggör monolitisk integrering av byggstenar i kiselfotoniska platformar, med låga optiska förluster och relativt korta optiska längder. Sådana värmebaserade byggstenar förbrukar dock mer än 1mW per device. Opto-elektroniska aktuatorer är också tillgängliga för höghastighetsmodulering i kiselfotoniska platformar men lider av höga förluster och är långa.

Mikromekaniska aktuatorer för kiselfotonik kan bidra med den teknik som saknas för uppskalning av fotoniska kretsar. Kisel är ett material med utmärkta mekaniska egenskaper, och MEMS-aktuatorer kan därför designas på samma lager som används för vågledarna. Elektrostatiska MEMS-aktuatorer förbrukar väldigt lite energi (1nW statiskt läckage per device), kan uppnå optiska förluster på samma nivå som dagens termo-optiska devicer, på kortare längder, och har svarstider på mikrosekund-nivå. Dessa aktuatorer kräver dock partiell suspension av kiselstrukturer för att uppnå rörelse, vilket inte är en tillgänglig teknik i kiselfotoniska platformar, och representerar ytterligare utmaningar vad gäller paketering av devicer.

Forskningen som presenteras i denna avhandling avser att föra storskaliga kiselfotoniska närmare kretsar verhligheten genom integration av MEMS-aktuatorer. MEMS-baserade byggstenar med skalbar optisk prestande utvecklades och inkluderades i fotoniska kretsar. Alla devicer och kretsar implementerades i en kiselfotonisk plattform (IMEC’s iSiPP50G) med några platformskompatibla efterbehandlingssteg. Slutligen utvecklades en lösning för försegling på wafer-nivå av dessa MEMS-aktuatorer, som är kompatibel med efterföljande paketering och som förbättrar den mekaniska prestandan hos dessa devicer.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2022. , p. 108
Series
TRITA-EECS-AVL ; 2022:71
Keywords [en]
Photonics, silicon photonics, MEMS, photonic MEMS, 3D printing, liquid crystals, programmable photonics, phase shifters, optical switches, ring resonators
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Electrical Engineering
Identifiers
URN: urn:nbn:se:kth:diva-321054ISBN: 978-91-8040-403-7 (print)OAI: oai:DiVA.org:kth-321054DiVA, id: diva2:1708575
Public defence
2022-11-25, F3, Lindstedtsvägen 26, Stockholm, 09:00 (English)
Opponent
Supervisors
Funder
EU, Horizon 2020, 66821
Note

QC 20221104

Available from: 2022-11-04 Created: 2022-11-04 Last updated: 2022-11-09Bibliographically approved
List of papers
1. Silicon photonic microelectromechanical phase shifters for scalable programmable photonics
Open this publication in new window or tab >>Silicon photonic microelectromechanical phase shifters for scalable programmable photonics
Show others...
2021 (English)In: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 46, no 22, p. 5671-5674Article in journal (Refereed) Published
Abstract [en]

Programmable photonic integrated circuits are emerging as an attractive platform for applications such as quantum information processing and artificial neural networks. However, current programmable circuits are limited in scalability by the lack of low-power and low-loss phase shifters in commercial foundries. Here, we demonstrate a compact phase shifter with low-power photonic microelectromechanical system (MEMS) actuation on a silicon photonics foundry platform (IMEC’s iSiPP50G). The device attains (2.9π±π) phase shift at 1550 nm, with an insertion loss of (0.33\textminus0.10$+$0.15)dB, a Vπ of (10.7\textminus1.4$+$2.2)V, and an Lπ of (17.2\textminus4.3$+$8.8)µm. We also measured an actuation bandwidth f\textminus3dB of 1.03 MHz in air. We believe that our demonstration of a low-loss and low-power photonic MEMS phase shifter implemented in silicon photonics foundry compatible technology lifts a main roadblock toward the scale-up of programmable photonic integrated circuits.

Place, publisher, year, edition, pages
OSA, 2021
Keywords
Crosstalk; Grating couplers; Neural networks; Phase shift; Quantum information processing; Silicon photonics
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-305507 (URN)10.1364/OL.436288 (DOI)000718386600038 ()34780433 (PubMedID)2-s2.0-85119082631 (Scopus ID)
Projects
MORPHIC
Funder
EU, Horizon 2020, 780283
Note

QC 20220426

Available from: 2021-12-01 Created: 2021-12-01 Last updated: 2022-11-04Bibliographically approved
2. Wafer-level hermetically sealed silicon photonic MEMS
Open this publication in new window or tab >>Wafer-level hermetically sealed silicon photonic MEMS
Show others...
2022 (English)In: Photonics Research, ISSN 2327-9125, Vol. 10, no 2, p. A14-A21Article in journal (Refereed) Published
Abstract [en]

The emerging fields of silicon (Si) photonic micro–electromechanical systems (MEMS) and optomechanics enable a wide range of novel high-performance photonic devices with ultra-low power consumption, such as integrated optical MEMS phase shifters, tunable couplers, switches, and optomechanical resonators. In contrast to conventional SiO2-clad Si photonics, photonic MEMS and optomechanics have suspended and movable parts that need to be protected from environmental influence and contamination during operation. Wafer-level hermetic sealing can be a cost-efficient solution, but Si photonic MEMS that are hermetically sealed inside cavities with optical and electrical feedthroughs have not been demonstrated to date, to our knowledge. Here, we demonstrate wafer-level vacuum sealing of Si photonic MEMS inside cavities with ultra-thin caps featuring optical and electrical feedthroughs that connect the photonic MEMS on the inside to optical grating couplers and electrical bond pads on the outside. We used Si photonic MEMS devices built on foundry wafers from the iSiPP50G Si photonics platform of IMEC, Belgium. Vacuum confinement inside the sealed cavities was confirmed by an observed increase of the cutoff frequency of the electro-mechanical response of the encapsulated photonic MEMS phase shifters, due to reduction of air damping. The sealing caps are extremely thin, have a small footprint, and are compatible with subsequent flip-chip bonding onto interposers or printed circuit boards. Thus, our approach for sealing of integrated Si photonic MEMS clears a significant hurdle for their application in high-performance Si photonic circuits.

Place, publisher, year, edition, pages
Optical Society of America, 2022
Keywords
Si photonics; MEMS; Hermetic sealing; Wafer-level vacuum packaging; Optical and electrical feedthrough; CMOS compatible; Thermo-compression bonding
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-308964 (URN)10.1364/prj.441215 (DOI)000750609100001 ()2-s2.0-85124172021 (Scopus ID)
Projects
MORPHICAEOLUSULISSESZeroAMP
Funder
EU, Horizon 2020, 780283EU, Horizon 2020, 101017186EU, Horizon 2020, 825272EU, Horizon 2020, 871740
Note

QC 20220303

Available from: 2022-02-17 Created: 2022-02-17 Last updated: 2022-11-04Bibliographically approved
3. A vacuum-sealed silicon photonic MEMS tunable ring resonator with independent control over coupling and phase
Open this publication in new window or tab >>A vacuum-sealed silicon photonic MEMS tunable ring resonator with independent control over coupling and phase
Show others...
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Ring resonators are a vital element for designing filters, optical delay lines, or sensors in silicon photonics. However, reconfigurable ring resonators with low-power consumption and good optical performance are not available in foundries today. We demonstrate an add-drop ring resonator with the independent tuning of coupling and round-trip phase using low-power microelectromechanical (MEMS) actuation. The MEMS rings are individually vacuum-sealed on wafer scale, enabling reliable long-term operation with low damping. On resonance, we demonstrate a modulation increase of up to 15 dB, with a voltage bias of 4V and a peak drive amplitude as low as 20mV.

Keywords
Silicon photonics, photonic MEMS, programmable photonics, telecommunications, ring filter
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-321053 (URN)
Funder
EU, Horizon 2020, 66821
Available from: 2022-11-04 Created: 2022-11-04 Last updated: 2022-11-04Bibliographically approved
4. A Bistable Silicon Photonic Mems Phase Switch For Nonvolatile Photonic Circuits
Open this publication in new window or tab >>A Bistable Silicon Photonic Mems Phase Switch For Nonvolatile Photonic Circuits
Show others...
2022 (English)Conference paper, Published paper (Refereed)
Abstract [en]

Silicon photonic circuits are rapidly growing in complexity and spreading to new applications. However, programmable circuits consume much power and require active electrical interfaces. For the first time, we demonstrate a nonvolatile photonic MEMS π-phase switch using dual comb-drive actuation and adhesion forces, implemented in a silicon photonics foundry. Both nonvolatile states are low-loss, display low dispersion, could be cycled through over 100 times, and have retention times over 12 hours. We believe that the demonstrated nonvolatility combined with excellent optical performance can enable a new generation of programmable photonic chips that do not consume any electrical power once (re)configured.

National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-308938 (URN)10.1109/MEMS51670.2022.9699739 (DOI)000784358100253 ()2-s2.0-85126396299 (Scopus ID)
Conference
MEMS 2022
Funder
EU, Horizon Europe, 66821
Note

QC 20220524

Available from: 2022-02-16 Created: 2022-02-16 Last updated: 2022-11-04Bibliographically approved
5. Broadband Compact Single-Pole Double-Throw Silicon Photonic MEMS Switch
Open this publication in new window or tab >>Broadband Compact Single-Pole Double-Throw Silicon Photonic MEMS Switch
Show others...
2021 (English)In: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 30, no 2, p. 322-329Article in journal (Refereed) Published
Abstract [en]

Photonic Integrated Circuits (PICs) benefit from the technology advances in the semiconductor industry to incorporate an ever-increasing number of photonic components on a single chip to create large-scale photonic integrated circuits. We here present a broadband, compact and low-loss Silicon Photonic MEMS switch based on a Single-Pole Double-Throw (SPDT) architecture, where curved electrostatic actuators mechanically displace a movable input waveguide to redirect the optical signal on chip efficiently to either of two output waveguides. The photonic switch has been fabricated in an established silicon photonics technology platform with custom MEMS release post-processing. With a compact footprint of $\mathbf 65\times 62\, \boldsymbol μ \mathbf m^\mathbf 2$ , the switch exhibits an extinction ratio exceeding 23 dB over 70 nm optical bandwidth, a low insertion loss and a fast response time below $1 μ \texts$ , meeting the requirements for integration in large-scale reconfigurable Photonic Integrated Circuits. [2020-0391]

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2021
Keywords
Optical waveguides;Optical switches;Photonics;Couplings;Optical coupling;Electrodes;Silicon;Microelectromechanical systems;photonic integrated circuits;silicon photonics;photonics;optical switch
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-292502 (URN)10.1109/JMEMS.2021.3060182 (DOI)000638400700018 ()2-s2.0-85101815080 (Scopus ID)
Projects
MORPHIC
Funder
EU, Horizon 2020, 780283
Note

QC 20210607

Available from: 2021-04-07 Created: 2021-04-07 Last updated: 2022-11-04Bibliographically approved
6. Low power optical phase shifter using liquid crystal actuation on a silicon photonics platform
Open this publication in new window or tab >>Low power optical phase shifter using liquid crystal actuation on a silicon photonics platform
Show others...
2022 (English)In: Optical Materials Express, E-ISSN 2159-3930, Vol. 12, no 6, p. 2181-2198Article in journal (Refereed) Published
Abstract [en]

Low-power and compact phase shifters are crucial for large photonic circuits, both to cope with variability and to create programmable waveguide circuits scaling to thousands of tuning elements. This work demonstrates a liquid crystal phase shifter where a lateral silicon electrode "rail" on one side of the waveguide core. Using this architecture, a strong quasi-static electric field Eactuation can be applied over the gap, which is filled with liquid crystal cladding material, with modest voltages. Because the mode is largely confined in the waveguide, optical losses are limited, compared to earlier experiments with slot waveguides. The liquid crystal is deposited locally on three different device variations using inkjet printing. The local deposition avoids unwanted interference of the liquid crystal with other optical components such as grating couplers. Measurements show similar trends as simulations of the liquid crystal orientations. For one device with a length of 50∼µm, a phase shift of almost 0.9π is shown at 10∼VRMS. We also discuss the challenges with this first demonstration of this phase shifter geometry using a silicon side-rail as an electrode.

Place, publisher, year, edition, pages
Optica Publishing Group, 2022
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-315255 (URN)10.1364/OME.457589 (DOI)000810930800001 ()2-s2.0-85130602076 (Scopus ID)
Note

QC 20220630

Available from: 2022-06-30 Created: 2022-06-30 Last updated: 2024-09-04Bibliographically approved
7. Three-dimensional printing of silica-glass structures with submicrometric features
Open this publication in new window or tab >>Three-dimensional printing of silica-glass structures with submicrometric features
Show others...
(English)Manuscript (preprint) (Other academic)
National Category
Other Materials Engineering
Identifiers
urn:nbn:se:kth:diva-269423 (URN)
Note

QC 20200313

Available from: 2020-03-06 Created: 2020-03-06 Last updated: 2022-11-04Bibliographically approved

Open Access in DiVA

summary(35087 kB)751 downloads
File information
File name SUMMARY01.pdfFile size 35087 kBChecksum SHA-512
1e27495897ba45d876d5dacaa49afbe378af16237e2a09d7d8d8c92cc708a2d0c125c7d0476f6f0e9910680f6ffb7a40fe9ef5e3ff7ad3f15d8b552ee6df02bc
Type summaryMimetype application/pdf

Other links

Zoom link for online defense

Authority records

Edinger, Pierre

Search in DiVA

By author/editor
Edinger, Pierre
By organisation
Micro and Nanosystems
Other Electrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 1889 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • 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