WO2004099864A2 - Transducteur electro-optique - Google Patents

Transducteur electro-optique Download PDF

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Publication number
WO2004099864A2
WO2004099864A2 PCT/NL2004/000308 NL2004000308W WO2004099864A2 WO 2004099864 A2 WO2004099864 A2 WO 2004099864A2 NL 2004000308 W NL2004000308 W NL 2004000308W WO 2004099864 A2 WO2004099864 A2 WO 2004099864A2
Authority
WO
WIPO (PCT)
Prior art keywords
optical
transducer
layer
layers
electrodes
Prior art date
Application number
PCT/NL2004/000308
Other languages
English (en)
Other versions
WO2004099864A3 (fr
Inventor
Joseph Wilhelmus Maria Hoekstra
Marcel Hoekman
René Gerrit Heideman HEIDEMAN
Original Assignee
Lionix B.V.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lionix B.V. filed Critical Lionix B.V.
Publication of WO2004099864A2 publication Critical patent/WO2004099864A2/fr
Publication of WO2004099864A3 publication Critical patent/WO2004099864A3/fr

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/22—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
    • C23C16/30—Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/03—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on ceramics or electro-optical crystals, e.g. exhibiting Pockels effect or Kerr effect
    • G02F1/035—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on ceramics or electro-optical crystals, e.g. exhibiting Pockels effect or Kerr effect in an optical waveguide structure
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/21—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  by interference
    • G02F1/225—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  by interference in an optical waveguide structure

Definitions

  • the invention relates to an electro-optical transducer, comprising at least two electrodes and at least one optical layer placed between the electrodes and manufactured from a light-transmitting, electro-optical material, the optical properties of this layer depending on the strength of an electric field applied by the electrodes over the layer.
  • Such a transducer is known from NL-A-1 006 323.
  • Such a transducer is adapted to conduct transversely of the direction of the electric field the light supplied to the transducer and to influence it subject to the strength of the electric field.
  • a minimal layer thickness of the optical layer is required. The inventors have found that the effectiveness of the transducer greatly decreases as the optical layer thickness increases, so that further increasing the layer thickness has scarcely any effect.
  • the object of the invention is to provide such a transducer wherein a good effectiveness of the layer is obtained over the whole thickness, so that larger amounts of light can be switched.
  • optical layer is divided into optical sub-layers by separating layers extending substantially transversely of the direction of the electric field generated by the electrodes.
  • the transducer is found to be active only in the vicinity of one of the two boundary layers. This is the result of the presence of a depletion layer and an accumulation layer, which in any case only extend in the vicinity of one of the boundary surfaces.
  • a depletion layer and an accumulation layer which in any case only extend in the vicinity of one of the boundary surfaces.
  • the number of boundary surfaces increases, and therewith the number of depletion and accumulation layers.
  • the depletion and accumulation layers can extend through the whole thickness of the optical layer, whereby the desired effect will extend through a greater part of or the whole volume of the optical layer.
  • the volume will of course decrease due to the presence of the separating layers. This effect is however much smaller than the advantage achieved.
  • the number of separating layers depends of course on the dimensioning and the materials applied, but the inventors have found that a favourable effect is obtained when at least three optical sub-layers and at least two separating layers are applied.
  • the optimal effect is in general even more closely approximated when at least six optical sub-layers are applied and - consequently - five separating layers.
  • the inventors have also found that the desired effect is optimal when an optical layer is applied with a thickness smaller than 200 nm. This is of course related to the width of the depletion or accumulation layer. This dimension thus depends to a certain extent on the type of material used. With some materials an optimum is however achieved when the thickness of the layer is smaller than 50 nm.
  • the thickness of the separating layer is smaller than 20 nm. It will of course be apparent that, in order to make the adverse effect of the separating layer, i.e. screening of the light, as small as possible, the layer thickness must be as small as possible. Conversely, the thickness must be great enough that it must be possible to apply the layer reproducibly, controllably and with a uniform thickness using known techniques.
  • Yet another embodiment provides the measure that the total thickness of the assembled layer is smaller than 1 ⁇ m.
  • An optimum is hereby achieved between the generally conflicting requirements arising from production technology and functionality.
  • the advantages of the invention become particularly manifest when the optical sublayers substantially comprise zinc oxide.
  • Zinc oxide has been found to be a material where the thickness of the depletion layer and of the accumulation layer is limited, so that the advantages of the invention manifest themselves well. Other materials wherein similar effects related to layer thickness occur are however not precluded.
  • the separating layers are preferably manufactured from silicon nitride or silicon oxide.
  • the above stated structure is suitable for application as modulator for modulating optical signals such as are used for instance in glass fibre communication.
  • the electric signal applied to the electrodes is herein used to modulate the light signal before the light signal enters a glass fibre cable.
  • electro-optical transducer as a sensor for sensing and converting electric signals.
  • electric signals can be converted into light signals, transported in this form over a great distance and subsequently detected.
  • a method wherein the following steps are performed of: providing a substrate; arranging a first optical layer in this substrate; applying a subsequent separating layer to this optical layer; applying a subsequent optical layer to the subsequent separating layer; repeating the latter two steps; and arranging an electrode on either side of the thus formed structure.
  • the electrodes are preferably arranged last on the structure. Use is preferably made for applying the layers of the following techniques: sputtering, vapour deposition or chemical vapour deposition (CVD).
  • figure la shows a section through a first exemplary embodiment of a structure of a modulator according to the invention with a partial enlargement
  • figure lb shows a section through a first, comparable single structure according to the prior art, with a partial enlargement.
  • Figure la shows a structure of layers 22,23 applied (for instance by means of sputtering) to a substrate 24, for instance a silicon wafer, which together form an electro-optically active structure 2 according to the invention.
  • Structure 2 is built up of alternating sublayers 22 of zinc oxide, of for instance 100 nm thickness, and separating layers 23 of for instance silicon oxide of for instance 5 nm thickness.
  • figure 1 shows a structure 2' grown onto the same type of substrate 24' built up of a single zinc oxide layer 22' grown on a silicon oxide substrate 23'.
  • the zinc oxide can grow as crystalline columns 25,25' on a thin initial layer 20,20'.
  • Columns 25,25' can again have depleted grain boundary regions 251,251' in addition to semiconducting cores 252,252'.
  • the sub-layers 12 each consist of a part of an initial layer 10'.
  • the active volume part in the structure according to the invention 1 is therefore much greater than in the prior art single structure 1'.
  • the electro-optical effect of structure 1 according to the invention will therefore be much stronger than that of the prior art single structure 1' at a comparable thickness and comparable total volume.
  • Figure 2 shows a schematic view of a modulator according to the invention.
  • the modulator according to the invention comprises a stack of layers 22 and 23.
  • Layers 22 are the sub-layers of optically active material and layers 23 are the separating layers.
  • the optical sub-layers 22 are manufactured from zinc oxide and separating layers 23 are manufactured from silicon oxide. It will be apparent that both layers can be replaced by layers of other materials with the desired properties. The method by which the structure is manufactured will of course be a major consideration in the choice of the materials.
  • An electrode 24 is arranged on the top side of the structure and an electrode 25 is arranged on the bottom side of the stack. Both electrodes are manufactured from conductive material.
  • a controllable voltage source 26 is connected between the two electrodes 24 and 25. The voltage source 26 functions here as signal source. This source supplies the modulating signal.
  • a light source for instance a LED 27, which is adapted to generate light in the desired wavelength.
  • the light is carried to the entry surface of the modulator by means of an entry element 28.
  • an entry element 28 During propagation of the light through the demodulator it is subjected to the electric field being generated by electrodes 24, 25.
  • the influencing of the light beam being propagated through the optical layers is expressed as a phase shift of the light beam. This depends on the strength of the local electric field. When the electric field changes, so will the phase of the light beam.
  • the light signal being propagated through the modulator will hereby be modulated by the signal generated by voltage source 26 and applied to the electrodes.
  • an entry element 29 for entry of the modulated light coming from the modulator to a glass fibre cable 30 or other light conductor.
  • the sensor can herein be used to sense the voltage applied to the electrodes. It is however also possible to use the sensor to measure other quantities having an effect on the diffraction of the optical layers, such as the temperature.
  • Phase modulation is not easy to detect without reference signal.
  • the obtained phase modulation can be converted into an amplitude modulation.
  • the measured signal can be converted into a change of intensity with the Mach-Zender interferometer.
  • a configuration of a Mach-Zender interferometer can be readily implemented in the technology applied here. A schematic top view of such a configuration is shown in figure 3 and a cross-sectional view thereof is shown in figure 4. This configuration is applicable in the use of the transducer as modulator as well as in the use of the transducer as sensor.
  • Such a structure is arranged on a substrate 20 of for instance silicon.
  • an optical bridge structure is arranged with two branches, each incorporating a modulator according to the present invention.
  • One of the sensors is herein screened from the immediate vicinity. This serves solely as reference and thereby as compensation for undesirable influences.
  • Both optical branches are together connected to a light source, such as a glass fibre cable, while they are both also connected to a second glass fibre cable for receiving the modulated signal.
  • transducer according to the present invention can likewise be applied in other signal-processing components.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Organic Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physical Vapour Deposition (AREA)
  • Piezo-Electric Transducers For Audible Bands (AREA)
  • Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)

Abstract

L'invention concerne un transducteur électro-optique comprenant au moins deux électrodes et au moins une couche optique placée entre les électrodes et fabriquée à partir d'un matériau électro-optique, émetteur de lumière, les propriétés optiques de cette couche dépendant de la force d'un champ électrique appliqué par les électrodes sur la couche, cette couche optique étant divisée en sous-couches optiques par séparation de couches s'étendant de façon sensiblement transversale par rapport au sens du champ électrique produit par les électrodes. Le transducteur se révèle actif uniquement à proximité d'une des deux couches limites du fait de la présence d'une couche de déplétion et d'une couche d'accumulation, qui de toute manière s'étendent uniquement à proximité d'une des surfaces limites. En produisant des couches de séparation supplémentaires, le nombre de surfaces limites augmente, ainsi le nombre de couches de déplétion et d'accumulation aussi. L'effet souhaité va donc s'étendre à travers une plus grande partie de la couche optique ou du volume total de celle-ci.
PCT/NL2004/000308 2003-05-09 2004-05-10 Transducteur electro-optique WO2004099864A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1023376A NL1023376C2 (nl) 2003-05-09 2003-05-09 Dunne laag en werkwijze voor het vervaardigen van een dunne laag.
NL1023376 2003-05-09

Publications (2)

Publication Number Publication Date
WO2004099864A2 true WO2004099864A2 (fr) 2004-11-18
WO2004099864A3 WO2004099864A3 (fr) 2005-03-17

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NL2004/000308 WO2004099864A2 (fr) 2003-05-09 2004-05-10 Transducteur electro-optique

Country Status (2)

Country Link
NL (1) NL1023376C2 (fr)
WO (1) WO2004099864A2 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006062526A2 (fr) * 2004-05-21 2006-06-15 Coveytech, Llc Dispositif optique et circuit utilisant la modulation de phase et procedes associes
US9703172B2 (en) 2006-02-14 2017-07-11 John Luther Covey All-optical logic gates using nonlinear elements—claim set V

Citations (5)

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Publication number Priority date Publication date Assignee Title
EP0154504A2 (fr) * 1984-02-28 1985-09-11 Exxon Research And Engineering Company Dispositifs électro-optiques comprenant un super-réseau
US5194983A (en) * 1986-11-27 1993-03-16 Centre National De La Recherche Scientifique (C.N.R.S.) Superlattice optical monitor
EP0631168A1 (fr) * 1993-06-25 1994-12-28 Nec Corporation Modulateur optique à semi-conducteur utilisant un superréseau du type II
WO2002061498A1 (fr) * 2001-01-30 2002-08-08 3Dv Systems, Ltd. Modulateur optique
US20030015737A1 (en) * 1999-10-25 2003-01-23 Intel Corporation Integrated semiconductor superlattice optical modulator

Family Cites Families (3)

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Publication number Priority date Publication date Assignee Title
US4923526A (en) * 1985-02-20 1990-05-08 Mitsubishi Denki Kabushiki Kaisha Homogeneous fine grained metal film on substrate and manufacturing method thereof
KR970072057A (ko) * 1996-04-04 1997-11-07 윌리엄 비. 켐플러 반도체 제조 공정시 입자 성장을 제어하는 방법
JP3477148B2 (ja) * 1999-12-02 2003-12-10 カーディナル・シージー・カンパニー 耐曇り性透明フィルム積層体

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0154504A2 (fr) * 1984-02-28 1985-09-11 Exxon Research And Engineering Company Dispositifs électro-optiques comprenant un super-réseau
US5194983A (en) * 1986-11-27 1993-03-16 Centre National De La Recherche Scientifique (C.N.R.S.) Superlattice optical monitor
EP0631168A1 (fr) * 1993-06-25 1994-12-28 Nec Corporation Modulateur optique à semi-conducteur utilisant un superréseau du type II
US20030015737A1 (en) * 1999-10-25 2003-01-23 Intel Corporation Integrated semiconductor superlattice optical modulator
WO2002061498A1 (fr) * 2001-01-30 2002-08-08 3Dv Systems, Ltd. Modulateur optique

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
OHTOMO A ET AL: "NOVEL SEMICONDUCTOR TECHNOLOGIES OF ZNO FILMS TOWARDS ULTRAVIOLET LEDS AND INVISIBLE FETS" IEICE TRANSACTIONS ON ELECTRONICS, INSTITUTE OF ELECTRONICS INFORMATION AND COMM. ENG. TOKYO, JP, vol. E83-C, no. 10, October 2000 (2000-10), pages 1614-1617, XP000970183 ISSN: 0916-8524 *
ZUCKER J E ET AL: "MINIATURE MACH-ZEHNDER INGAASP QUANTUM WELL WAVEGUIDE INTERFEROMETERS FOR 1.3 M" IEEE PHOTONICS TECHNOLOGY LETTERS, IEEE INC. NEW YORK, US, vol. 2, no. 1, January 1990 (1990-01), pages 32-34, XP000114129 ISSN: 1041-1135 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006062526A2 (fr) * 2004-05-21 2006-06-15 Coveytech, Llc Dispositif optique et circuit utilisant la modulation de phase et procedes associes
WO2006062526A3 (fr) * 2004-05-21 2006-12-07 Coveytech Llc Dispositif optique et circuit utilisant la modulation de phase et procedes associes
US7657188B2 (en) 2004-05-21 2010-02-02 Coveytech Llc Optical device and circuit using phase modulation and related methods
EP2284606A3 (fr) * 2004-05-21 2011-04-20 Coveytech, LLC Dispositif optique et circuit utilisant la modulation de phase et procedes associes
EP2275863A3 (fr) * 2004-05-21 2011-04-27 Coveytech, LLC Dispositif optique et circuit utilisant la modulation de phase et procedes associes
US9703172B2 (en) 2006-02-14 2017-07-11 John Luther Covey All-optical logic gates using nonlinear elements—claim set V

Also Published As

Publication number Publication date
NL1023376C2 (nl) 2004-11-15
WO2004099864A3 (fr) 2005-03-17

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